JP2002523969A - Stack carrier discrete multitone communication technology - Google Patents

Abstract

Abstract: A "stack carrier" spread spectrum communication system (10) is based on frequency domain spreading that multiplies the time domain representation of a baseband signal by a set of superimposed, or stacked, complex sinusoidal carriers. I have. In the preferred embodiment (10), diffusion activates the bins of the large-scale fast Fourier transform (FFT). This significantly reduces the computational complexity of a reasonable output FFT size. Point-to-multipoint and many-to-many (nodeless) network topologies are possible. Code nulling methods are included to provide interference cancellation and enhanced signal separation by utilizing the spectral diversity of the various sources (11). The basic system (10) may be extended to also include a multi-element antenna array (26/18) nulling method for interference cancellation and enhanced signal separation using spatial separation. Such a method allows for directional and retro-directional transmission systems that can be adapted to or adapted to a wireless environment. Such systems are compatible with bandwidth-on-demand and higher order modulation formats and use the latest (maximum SINR) despreader adaptation algorithm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to wireless communications, and more particularly, to communication techniques for multiple access in difficult challenging environments combined with dynamic environmental changes.

[0002]

[Prior art]

Communication technologies developed during the 1940's during World War II include "frequency diversity communication" or "stack carrier communication" to assist in high frequency (HF) band traffic. J.Proakis published in 1989 by McGraw-Hill, Inc.
Sections 7.4 to 7.7 of "Frequency Diversity Communication Technology in Digital Communication". The diversity technique described by J. Proakis is based on the problem that the reception of a channel with large attenuation, i.e. a channel with large fading, causes errors. When the receiver is provided with multiple copies of the original signal on multiple channels whose fading states are independent of each other,
Except for an abnormal state in which all the replica channels are both faded and attenuated together, there is a high possibility of ensuring continuous communication. Such a probability can be evaluated.

[0003] Frequency diversity is one of many diversity methods. The same modulated signal is transmitted over several carrier channels separated by a nominal coherent bandwidth of each channel. In time diversity, the same information is transmitted in different time slots. In a diversity scheme, multiple antennas can be used. Multiple receive antennas can be used to receive signals sent from a single transmit antenna. The best effect is that the receiving antennas are sufficiently spaced apart to vary the different multipath disturbances between groups. A nominal 10 wavelength separation distance is generally required for independent signal fading to be observed.

[0004] Signals having a bandwidth much larger than the coherent bandwidth of the channel can be used in more complex diversity schemes. Such a signal with bandwidth W resolves multipath components and provides a receiver with multiple independent fading signal paths. Other conventional diversity techniques include angle of arrival or space diversity and polarization diversity.

When a bandwidth W that is much larger than the coherent bandwidth of each channel is available to the user, the channels are manually separated by at least the center frequency of the coherent bandwidth of each channel. It can be subdivided into frequency multiplexed sub-channels. Thereafter, the same signal is transmitted on a frequency division multiplexed sub-channel and can perform a frequency diversity operation. Similar results can be obtained by using a wideband binary signal covering the bandwidth W.

GKKaleh's literature (IEEE Transaction on Communication, September 1944)
Provides an overview of safe settings that operate in environments that are detrimental to signal caution.

[0007] J. Proakis describes the concept of frequency diversity spread spectrum and multiple access in Chapter 8 of the aforementioned reference. Diversity transmission in combination with frequency hopping spread spectrum has been described in detail for multiple fading and partial band jamming.

[0008] Retrodirectivity was already proposed in 1959 and has been used and adapted to multi-element antenna arrays to provide the same spatial gain pattern during transmit and receive operations. For such a technique, reference may be made to US Pat. No. 2,908,002 and US Pat. No. 4,383,332. TDD systems provide an effective means of constructing older directional antenna arrays, for example, by minimizing channel changes between the receive and transmit paths.

[0009]

[Problems to be solved by the invention]

Therefore, it is an object of the present invention to store data over widely separated frequency bands that clarify channel distortion differences without physical spread signals between intervening frequencies as required by the direct sequence spread spectrum. The object is to provide a wireless communication system for spreading.

It is another object of the present invention to provide a wireless communication system, for example, for communicating normal cellular signal waveforms under strong narrowband interference by switching off affected frequency channels in a receiver despreader. is there. It is another object of the present invention to provide a wireless communication system with simple equalization of linear multipath distortion. It is another object of the present invention to provide a wireless communication system compatible with discrete multitone and orthogonal frequency division multiplexing channelization techniques. It is also compatible with discrete multitone and orthogonal frequency division multiplexing modulation / demodulation techniques that are time packetized for frequency channelization and dechannelization.

Another object of the present invention is to generate a stacked carrier spread spectrum signal using, for example, discrete multitone and / or orthogonal frequency division multiplexing based frequency channelizers and dechannelizers. In some cases, it is an object of the present invention to provide a wireless communication system compatible with a time division duplex system in which a stacked carrier spread spectrum format is packetized.

Another object of the present invention is to provide a multiple access capacity wireless communication system such as frequency division multiple access. It is another object of the present invention to provide a wireless communication system with a capacity similar to stack carrier multiple access, such as code division multiple access. It is another object of the present invention to provide a wireless communication system compatible with higher order digital modulation.

Another object of the present invention is to provide a wireless communication system for bandwidth-on-demand flexible data rate connection. It is yet another object of the present invention to provide a wireless communication system in code null applications for multiple access, such as space division multiple access, jamming rejection, and channel equalization capabilities. Another object of the invention is to spatially extend the spread code to spread the data using independent complex gains for each spatial channel or antenna beam to control the dispersion of the channel bandwidth array Accordingly, it is an object of the present invention to provide a wireless communication system for using an adaptive antenna array.

Another object of the present invention is to take advantage of the underlying characteristics of baseband data, channel structure, or stack carrier spread format, such as non-blind pilot commands, blind data commands, and other techniques. To provide a wireless communication system compatible with a new array adaptation technology.

Another object of the present invention is to provide a wireless communication system compatible with retro-directional communication technology. It is another object of the present invention to provide a conventional code division multiple access, data activation system and back compatible wireless communication system.

[0016]

[Means for Solving the Problems]

Briefly, one embodiment of the present invention includes a "stack carrier" spread spectrum communication system. In that system, the spread is 1
This is done in the frequency domain by multiplying the time domain representation of the baseband signal by a set of superimposed or stacked complex sinusoidal carrier carriers. In practice, the spreading is done by simply energizing the large Fast Fourier Transform (FFT) bins. This saves a great deal of computational complexity for a moderate output FFT size. For example, a Kaiser-Bessel window with β = 9 can be used to fill the space between tones without exposing the tones to unacceptable interference from adjacent tones, eg, inter-tone interference. In practice, high values of β will give acceptable interference with adjacent tones and very low interference with distant tones. This basic technique is then combined with time division duplex, code division multiple access, space division multiple access, frequency division multiple access, adaptive antenna arrays, and interference and interference cancellation techniques.

An advantage of the present invention is that a wireless communication method is provided that spreads data over a wide discrete frequency band for spectrum diversity. This provides an effective and efficient way to take advantage of frequency diversity, especially in applications where the bands are very widely separated. An advantage of the present invention is also that a wireless communication method is provided that communicates even under strong narrowband interference. Therefore, Stacked Carrier Spread Spectrum (SCSS) links are required for strong narrowband frequency division multiple access (F) such as cellular overlay applications.
DMA) and time division multiple access (TDMA) cellular radio signals can also be maintained. Such a link can also be maintained in the presence of spurious interference due to out-of-band signal harmonics.

The advantages of the present invention also enable simple equalization of linear channel distortion,
Or a wireless communication method is provided that allows quasi-stationary linear channel distortion to be approximated as an increased effect on the transmitted spread code. It further allows the de-spreading or spreading operation to include a channel equalization operation without additional filtering, except for the removal of Doppler spread in the packet. The basic technologies are baseband bandwidth, prespread,
Equalize multipath dispersion to the same extent as message signals. This multipath equalization operation can be very simple if the bandwidth of the message signal is low. If the bandwidth of the pre-spread message signal is sufficiently low, for example, if the correlation width or inverse bandwidth of the pre-spread message signal is many times the maximum multipath delay in the transmission channel, etc. The binning operation is reduced to a complex multiplication operation, which is automatically included during the adaptive despread operation. This is a normal C
In contrast to DMA systems, conventional CDMA systems require additional equalization even when the spread width of the spread signal is many times the maximum multipath delay in the transmission channel.

Another advantage of the present invention is that it provides a wireless communication method that is compatible with discrete multitone and orthogonal frequency division multiplexing frequency channeling techniques. This makes it possible to model static and linear channel distortions as the exact increasing effect on the transmitted spread code. Another advantage of the present invention is that it provides a wireless communication method that is compatible with time division duplex systems. Therefore, the time division duplex communication format can be used when the stack carrier spread spectrum modulation format is packetized, for example, when the stack carrier spread spectrum signal is a discrete multitone and orthogonal frequency division multiplex based frequency. It can be used when generated using at least one of a channelizer and a reverse channelizer. "Local" evaluation of the transmission channel at either end of the communication link is possible, greatly simplifying channel pre-emphasis, transmission position channel equalization topology, and retro-directional transmission techniques.

Another advantage of the present invention is that it has multiple access capability code division multiple access type,
For example, a wireless communication method using a stack carrier multiple access method can be obtained. A point-to-multipoint communication link is constructed by transmitting signals over the same subset of frequency channels using a set of linear interdependent (orthogonal or non-orthogonal) spread gains to separate the signals at the despreader. You. An advantage of the present invention when used with code null technology is that it allows the use of non-orthogonal spread codes because the spread codes can be non-orthogonal.

Another advantage of the present invention is that it provides a wireless communication method that is compatible with "demand bandwidth" flexible data rate technology. The data rate provided on a given link can be increased or decreased in smaller increments for transmission primitives to a single user by multiple time, frequency, or stack carrier channels. Thereafter, if the data rate is adjusted and increased using multiple stacked carrier channels, the data rate can be adjusted without increasing the bandwidth.

Another advantage of the present invention is that it provides a wireless communication method that is compatible with advanced digital modulation. Compatible with any _Mary digital baseband modulation format,
Transmission of a high number of bits / symbol in each frequency channel allows for improved capacity. Reuse is improved and "load balancing" in multi-cell communication networks can be included by varying the number of bits per symbol in each primitive.

Another advantage of the present invention is that it provides a wireless communication method with space division multiple access, interference rejection, and channel equalization capabilities, for example, in code null technology. Such space-division multiple access-like code nulling techniques in optimal or sub-optimal linear jamming cancellation and signal extraction techniques are useful for separating stack carrier spread spectrum signals in a despreader based on signal frequency or spectrum diversity. The interference cancellation for the stacked carrier spread spectrum signal in the cell is thereby performed, while at the same time the cancellation of the interference outside the cell, eg the ability to enhance reuse, is obtained. This allows for the most efficient use of code null techniques generally applicable to a wide range of spread formats. In particular, it provides one factor of two performance improvements for code null techniques developed to use the direct sequence spread spectrum format of modulation for symbols. In that format, the spread gain repeats once for each underlying message symbol.

Another advantage of the present invention is that it provides a wireless communication method that can be used with an adaptive antenna array.

Another advantage of the present invention is that radios that separate signals based on spatial diversity, frequency spectrum diversity, polarization diversity, and combinations of space / frequency / polarization diversity are compatible with the new array adaptation techniques. A communication method is to be obtained.

Another advantage of the present invention is that it provides a wireless communication method that is compatible with retro directional communication technology. This enables a direct extension of spatial retrodirective techniques to a stacked carrier spread spectrum system that includes a single antenna or antenna array. It also allows the most complex centralized operation at the base station of a single point / multipoint communication link, significantly reducing the cost of the overall system.

Yet another advantage of the present invention is that a reverse wireless communication method is provided that is compatible with normal code division multiple access and data activation techniques.

These and other objects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, as illustrated in the various drawings.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 shows an embodiment of the communication system of the present invention, here referenced by reference numeral 10. System 10 is a base station for two-way wireless communication with a plurality of remote units 12-17.
11 is provided. The locations of remote units 12-17 around base station 11 in FIG. 1 represent various different locations in three dimensions that can be assumed by all or one or more remote units at various points in time. The base station 11 has a multi-element antenna 18. Each remote unit 12-17 has a corresponding antenna 19-24, some or all of which may include multi-element antennas, for example, antennas 21, 23,24. Antennas 18-24 are connected to transceivers to separate the transmitting and receiving antennas.
It represents an alternative ranging from one physical antenna to an array of antennas each representing a different spatial signal sensitivity. Further, some or all antennas 18-24 may be polarization diversity. That is, some antennas 18-24 are polarized with positive sensing (e.g., antenna 20) and some antennas are negatively polarized (e.g., antenna 22). "Positive / negative" polarization sensitivity is based on "horizontal / vertical" linear polarization, "clockwise / counterclockwise" circular polarization, "tilted 45/135" polarization, and the like. True noise penetrates system 10 equally from all directions, and the sources of interference and jamming are typically limited by signals arriving from a particular direction. Multipath signals between base station 11 and remote units 12-17 are indicative of a type of interference that causes channel fades and other problems.

The system 10 may also include a point-to-multipoint network and a point-to-point network topology as represented by a second base station 25 having a multi-element antenna 26. A multipoint-to-multipoint network is a superset of that shown in FIG. 1 and is useful in cellular systems where adjacent call interfaces need to be controlled. Each base station or remote unit transceiver in the network may have any different number of antenna elements and spreading elements, for example, which may be spread across different numbers of frequency cells. Spatially localized interference, jammers can arrive from other stack carrier networks and cells within the network and from other interferers, such as jamming or network-layered FDMA signals. True noise penetrates the system equally or unequally from all directions, where "equal" refers to isotropic noise.

The basic means of wireless communication of system 10 is referred to herein as the “stack carrier spread spectrum” (SCSS), where discrete multiple tones (DMTs) having substantial frequency diversity are transmitted to base station 11. And each remote device
Sent simultaneously to others by 12-17. One baseband data symbol is spread spectrum modulated with each set of discrete multitone transmissions from one device 11-17. Accurate data recovery can be achieved by the destination receiver even if several individual channels carrying information in discrete tones are lost or severely disturbed.

The present invention can be further represented in various ways, for example, in some combined embodiments shown in FIGS. 2A-6B. A to FIG. 6 of FIG.
Each of the main elements introduced in B will be described in further detail in combination with FIGS. 7-17. The antennas in each array can have any spatial arrangement, for example, the arrays do not require a special antenna shape to function correctly. In addition, antennas can differ in polarization as well as in space.

FIG. 2A shows a point-to-point transmitter 30 with a stacked carrier spread spectrum (SCSS) transmitter bank 32 connected to a multi-element array antenna (AA) 34. A point-to-point receiver 36 is a multi-element antenna array (AA) 38 connected to a stack carrier spread spectrum (SCSS) receiver bank 40.
Is provided. Each antenna array includes a plurality of spatially separated antennas for transmitting and receiving data. Adaptive antenna array processing, such as adaptive linear combination and / or transmission with multiple spatially separated antennas, is here, ie, in FIG. 2B, FIG. 6A or FIG. Not combined by spread and despread operations. The array matching process is not involved in the stack carrier spread and despread operations.

FIG. 2B shows a network transmitter 42 with a stacked carrier multiple access (SCMA) transmitter bank 44 connected to a multi-element antenna array (AA) 46. The network receiver bank 48 has a stack carrier multiple access (SC)
MA) comprising a multi-element antenna array (AA) 50 connected to a receiver bank 52.

FIG. 3A shows a point-to-point transmitter comprising a stack carrier spread spectrum (SCSS) transmitter 56 connected to a time division duplexer (TDD) 58.
54 is shown. Point-to-point receiver 60 includes a time division duplexer 62 connected to a stack carrier spread spectrum (SCSS) receiver 64.

FIG. 3B shows a network transmitter 66 including a stack carrier multiple access (SCMA) transmitter 68 connected to a time division duplexer (TDD) 70. Network receiver 72 includes a time division duplexer 74 connected to a stack carrier multiple access (SCMA) receiver 76.

FIG. 4A shows a point-to-point transmitter 78 including a stack carrier spread spectrum (SCSS) transmitter 80 connected to a code null 82. The point-to-point receiver 84 is a stack carrier spread spectrum (SCSS) receiver 88.
Contains a code null 86 connected to.

FIG. 4B illustrates a stack carrier multiple access (S) connected to code null 94.
A network transmitter 90 comprising a CMA) transmitter 92 is shown. Network receiver 96 includes a code null 98 connected to a stack carrier multiple access (SCMA) receiver 100.

FIG. 5A shows a point-to-point transmitter 102 including a stack carrier spread spectrum (SCSS) transmitter 104 connected to a widely separated frequency channelizer 106. Point-to-point receiver 108 comprises a widely separated frequency channelizer 110 connected to a stack carrier spread spectrum (SCSS) receiver 112.

FIG. 5B shows a network transmitter 114 including a stacked carrier multiple access (SCMA) transmitter 116 connected to a widely separated frequency channelizer 118. Network receiver 120 is a widely separated frequency channelizer connected to a stack carrier multiple access (SCMA) receiver 124.
Contains 122.

FIG. 6A shows a point-to-point transceiver system 126 in which a stack carrier spread spectrum (SCSS) transmitter bank 128 controls a stack carrier spread spectrum (SCSS) receiver bank 128. Below,
A retro adapter 136 connects to a synchronized time division duplexer (TDD) bank 130 which is connected to both a multi-element antenna array (AA) 132 and a stack carrier spread spectrum (SCSS) receiver bank 134.

FIG. 6B illustrates a stack carrier multiple access (SCMA) transmitter bank 140.
Under the control of, a retro-adapter 148 connects to a synchronized time division duplexer (TDD) 142 which is connected to both a multi-element antenna array (AA) 144 and a stacked carrier multiple access (SCMA) receiver bank 146. A network system 138 including a stacked carrier multiple access (SCMA) transmitter 140 is shown. .

FIG. 7 shows a stack carrier spread spectrum (SCSS) transmitter 150 similar to the transmitters included in A, 3A, 4A, 5A, and 6A of FIG. SCSS transmitter 150 includes a digital-to-analog converter (DAC) 152 that converts incoming digital data for transmission into an analog signal. Analog information for transmission may be directly input without the DAC 152. Two or more channels (eg, 1... K) are included, each of which modulates a corresponding radio frequency carrier in an up-conversion process. For example, each up-conversion channel comprises a 90 ° phase shifter 158 and an in-phase (I) mixer 154 and a quadrature (Q) mixer 156 connected to a local oscillator (LO) 160. Thus, the modulation information controls the in-phase and quadrature amplitudes of the AM carrier radio frequency. A pair of gain control amplifiers 162 and 164 allow independent adjustment of the in-phase and quadrature amplitudes, respectively, before being recombined by summing device 166. A band pass filter (BPF) 168 removes out-of-band signals that interfere with adjacent channels. The final summing unit 170 combines the signals from all channels to generate a transmitter output, which is then provided to an antenna, for example. Spread gain generator 172 periodically generates parallel outputs that control all gain controlled amplifiers 162, 164 for each channel as a group. Each gain controlled amplifier
Each control signal to 162 and 164 controls 1-bit on / off control and signal digital line for multi-bit parallel digital control for discrete gray scale setting or analog control for continuously variable gain setting. You may have.

An obvious variant of the analog circuit shown in FIGS. 7 and 8 for transmitter 150 and receiver 180 is, for example, an all-digital transmultiplexer (“transmux”) with discrete digital logic or a digital signal processor. ) Is to use the design.

Another preferred configuration for the direct or transmultiplexer spread and despread methods illustrated by the examples of FIGS. 7 and 8 is the discrete multitone (DMT) method of orthogonal frequency division multiplexing (OFDM) described herein. It is.

Referring to FIG. 7, in operation of the transmitter 150, this is not only obtained using a different spread gain output, but is also more easily received by the destination receiver. There may be some spread gain output from. The intervening wireless communication environment between the transmitter and the receiver typically attenuates or interferes with some phases and frequencies more than others. The wireless communication environment is more easily prevented by co-channel interference, additional internetworks, intra-networks, and spread codes that cannot be eliminated by the receiver / jamming /
Includes overlay signal. Therefore, the spread gain output has the ability to compensate for the effects of both the intervening wireless communication environment, channel distortion and co-channel interference. The optimal spread gain output generated at a time can be fixed in a patterned sequence according to time or place, or the communication quality,
For example, it is adjusted according to the results obtained from several types of measurements on the reverse channel data. The spread code compensates for co-channel interferers and channel distortion.

FIG. 8 shows a stack carrier spread spectrum (SCSS) receiver 180 similar to the receivers included in A, 3A, 4A, 5A, and 6A of FIG. This is a device corresponding to the transmitter 150 shown in FIG. SCSS receiver 180 receives the analog signal at splitter 181 which drives several parallel frequency division channels. A typical channel is a pair driven by a bandpass filter 182, a splitter 183, an in-phase gain controlled amplifier 184, a quadrature gain controlled amplifier 185, a phase shifter 188 and a local oscillator 189. 186 and 187 and an analog-to-digital converter (ADC) 190 that combines all receiver channels back into digital signals. Each down conversion channel comprises an in-phase (I) mixer 186 and a quadrature (Q) mixer 187 connected to a 90 ° phase shifter 188 and a local oscillator (LO) 189. Despread weight generator 191 includes individual in-phase and quadrature amplifiers 184, 18 for each channel.
5 connected to control.

The base station 230 is shown in FIG. For "code nulling"
By noting that the spread gain is obtained from the locally adapted despread weights of the preferred embodiment, the despread weight maximizes the signal-to-interference and noise ratio of the preferred embodiment despread message sequence, and And adapted to induce retro-directivity. Base station 230 is similar to base station 11 (FIG. 1) and is an antenna array for directional wireless communication with a remote device by beamforming.
232, transmit / receive (T / R) front end 234, and frequency channel bank
236, a data cell mapper 238, a weighted adaptation algorithm generator 240, a multi-antenna multi-link despreader 242, a delay and Doppler estimator 243, a delay and Doppler equalizer bank 244, and some recovered A symbol decoder bank such as a trellis decoder that outputs a baseband data channel
246. Some or all antennas of antenna array 232 may be polarization-diverse (eg, antenna 233) or no such antenna may be present.

Several output baseband data channels are connected to a symbol encoder bank 248, for example a trellis encoder. From there, the transmissions are transmitted to a delay and Doppler pre-emphasis bank 250, a multi-antenna multi-link spreader 252, an antenna and frequency channel mapper 254, a transmit / receive compensation bank 255 connected to a transmit / receive compensation algorithm generator 256, T / It includes an inverse frequency channelizer bank 257 connected to the R front end 234. The transmit / receive packet trigger 258 receives the GPS time transfer information,
It controls the interleaving and duration of the individual transmit and receive times of the front end 234. A base station can also have as few as one antenna element in its array. In a preferred embodiment, the base station uses a packetized time division duplex DMT or OFDM modulator and demodulator to perform the inverse frequency channelizer and frequency channelizer operations.

Further information on alternative uses of trellis coded modulation can be found in Boulle's “An Over
view of Trellis Coded Modulation Research in COST 231 ”IEEE PIMRC '94,
See pages 105-109.

Remote device 260 is shown in FIG. 10 in a preferred embodiment. Remote unit 260 is similar to remote units 12-17 (FIG. 1), and includes an antenna array 262 for wireless communication with a base station via combined spatial and spectral diversity, and a transmit / receive (T / R).
) Front end 264, frequency channel bank 266, data cell mapper 26
8, a weighted adaptation algorithm generator 270, a multi-antenna despreader 272, a delay and Doppler estimator 273, a delay and Doppler equalizer 274, such as a data decoder that outputs a recovered baseband data channel. And a simple symbol decoder 276. Some or all antennas of antenna array 262 may be polarization-diverse (eg, antenna 263) or no such antenna may be present.

The output baseband data channel is connected to a symbol encoder 278, for example, a data encoder. The transmission further includes a delay / Doppler pre-emphasis unit 280, a multi-antenna spreader 282, an antenna and frequency channel mapper 284, a transmit / receive compensation bank 285 connected to a transmit / receive compensation algorithm generator 286, a T / R front end 264. And a reverse frequency channelizer bank 287 connected to the Transmit / receive packet trigger 28
8 receives GPS time transfer information and controls the interleaving and duration of the individual transmit and receive times of the T / R front end 264.

The remote unit can also have as few as one antenna element in its array. The number of antennas for each remote device may vary from device to device. This allows the remote device to have a variable price based on importance and the data rate used by a given device. Remote devices have different spread rates. They can spread their data over different subsets of the frequency channels used by the base station transceiver. In a preferred embodiment, the remote unit uses a packetized time division duplex DMT or OFDM modulator and demodulator to perform the inverse frequency channelizer and frequency channelizer operations. The difference between the base station and the remote unit is that the base station transceiver signals from multiple nodes, eg, multiple accesses. Each remote unit sends and receives only one stream of data destined for it. Channel equalization techniques and code nulls are a limited way of adapting spread and despread weights.

FIG. 11 shows a multi-antenna transmission / reception module 290. Module 290 includes a multi-element antenna array 291 with each element connected to a corresponding one of the channel T / R modules 292, for example, four in number. Each T / R module 292 is connected to a packet trigger 293, a receiver calibration generator 294, a local oscillator 295 and a system clock 296. These are driven by a GPS clock and a Doppler correction signal. Each T / R module 292 includes a T / R switch 297, an intermediate frequency (IF) down converter 298, and an analog / digital converter (AD).
C) 299, a digital-to-analog converter (DAC) 300, an IF up-converter 301, and a power amplifier (PA) 302. The receive weight information is learned during the receive process and is used in the transmit process to set the relative transmit power provided to each antenna element, for example, to compensate for channel cancellation (fade) or interference. It should be noted that if the base station is of diverse polarization diversity, the transmitting / receiving module must excite both polarizations separately.

[0055] Receive and transmit time slots are triggered at specific times, which can be, for example, from the Global Positioning System (GPS) maintained by the United States Department of Defense to an independent source of accurate, universally accessible time. Therefore, it may be determined pseudo-randomly. Such GPS time is obtained from a navigation system located on the communication platform, so that the receiver side of each T / R module 292 always knows the time slot to which the packet corresponds. GPS time is also used to derive the local oscillator and ADC / DAC clock used in the system. The receiver does not need to be synchronized to the remote transmission source. In particular, the distance between communications, propagation delay, and Doppler shift need not be known by the receiver system before receiving the first data packet. However, the distance, speed, delay and Doppler shift between correspondents may be known to some degree of accuracy in certain applications. The distance between the correspondents, the propagation delay, and the Doppler shift need not be known before receiving the first data packet.

The calibration mode is optional and is used only as needed. For example, intermittently, at the beginning of a given transmission, or when internal diagnostics indicate that such calibration is not required.

The encoding, spreading and modulation operations, for example as shown in FIG. 12, are preferably mirrored by similar demodulation, despreading and decoding operations as in FIG.
The data stream of FIG. 12 is reflected in FIG. 13 as a signal stream, for example, the same data stream is present in both FIG. 12 and FIG. 13, and the adder in one figure is fan-out (terminal extension mechanism) in the other figure. Has been replaced. Such symmetry is due to the DMT modulator and demodulator,
Examples are frequency mapping and inverse mapping operations, spread and despread operations, code gate spread and despread operations. The structure of the spreader reflects the structure of the despreader. Conventional CDMA transceivers do not have this symmetry. Thus, such symmetry is a critical feature in embodiments of the present invention.

FIG. 12 illustrates a discrete multi-tone stack carrier spread spectrum (SCSS) modulator used for frequency channelization in embodiment 300. Frame generation commands from the navigation and coding system 302 cause the signal modulator 304 to encode calendar, position, velocity, acceleration, and other messages into a K _cell symbol data vector. These symbols are then used to modulate a set of baseband tones or Fast Fourier Transform (FFT) bins. In spreader 306, the K _cell baseband tones are replicated across separate spread cells of K _spread and separate spread gains for antenna “1” and frequency cell “h” complex numbers, eg, the complex constant of each symbol multiplied equally by the cell. And passed through a time multiplexer that combines the cells into a K _active long vector of complex data, where K _active ≧ K _cell * K _spread . This complex data vector is sent to the zero padded inverse FFT operator 308, which directly converts the data vector to K _FFT ≧ (1 + SF) · K _active real IF time samples, where “SF” Indicates the "shape factor" or the ratio of the stopband to the passband of this system. The first E _roll K _FFT samples of this time sequence are then repeated at 310 to form a long data sequence of K _packet = (1 + E _roll ) K _FFT . Multiplier 312 multiplies this by K _packets of long data from Kaiser-Bessel window 314 to generate the final sampled signal. The sampled signal is then sent to a digital-to-analog converter,
The resulting long data burst of T _packet K _packet / f ₅ is sent to the frequency up-converter and the communication channel, where f ₅ is the complex sample rate of the DPC / DNC module. All the parameters used to reduce the characteristics of the transmitted signal are adjusted to GPS time and thus transmit simultaneously to the nodes of the communication network. This process is repeated for each antenna in the system.

Symbol encoding in baseband tones is included in the baseline system 300. Each K _cell data bit demodulates a separate tone in the signal baseband,
Thus, if the data bits modulating the tone are equal to zero or one, respectively, the tone is phase modulated by 0 or 180 °. Such tone modulation is highly efficient with respect to acceptable transmit power. This presents a vulnerability to radiometer detection techniques and allows for reliable demodulation of transmitted data bit sequences as low as 3 dB at E ₀ / N ₀ . The BPSK format, when based on the conjugate self-coherence of a tone phase sequence, allows a powerful and sophisticated method to remove timing and carrier offsets from a despread signal.

Such an operation is for example one antenna using a different complex spread gain _kl for each frequency cell k and antenna l used by the transceiver. The path uses the packet extension coefficient e _roll and the packet sample length K _packet = K _packet = (1 + e _roll ) K _FFT samples before the digital-to-analog conversion operation (T _{pack et} = (1 + e _roll ) T _FFT period after DAC operation). . The spread gain g _kl can be determined via a number of means, for example via a codebook, randomly, pseudo-randomly or adaptively based on the _despread weight w _kl .

The number of information bits per data symbol is K _bits . BPSK is a simple one
There are two encoding methods, where the encoding is ignored and K _bit = 1. Platform calendar, position, velocity, and acceleration information are examples of data transmitted in some applications. BPSK is the preferred modulation for applications where data rate is not a major issue of the system.

[0062] Delay and Doppler pre-emphasis operations are optionally included in another embodiment. This can be included after the first packet to remove the effects of delay and Doppler shift at the receiver, the destination of the signal transmitted from the DMT modulator. This operation simplifies the design of the network transceiver by allowing, for example, delay and Doppler removal operations to be concentrated at the base stations of the network.

As a generalization of the spread concept to multiple access transceivers, a separate set of spread gains (g _kl (m)) can be used for multiple user transceiver users m
Can be used to spread data symbols destined for.

FIG. 13 shows an all-digital fully compatible despread and beamforming receiver.
Machine 320 is shown. For background on this technology, see Tsoulos “Application of A
daptive Antenna Technology to Third Generation Mixed Cell Radio Architec
tures ", March 1994, IEEE # 1-7803-1927, pages 615-619. Receiver.
Frame receive commands from the navigation and coding system 322
The signal demodulator 324 has the K of the array antenna 326_arraySeries of T from_gateLong send
Aggregate frames and convert from analog to digital, where T_gateIs K_gate It is time for sample length. This is due to the unknown propagation delay (T _gate = T_packet+ T_guardT) to take into account_guardLong guard time
Slot, where T_packetIs the length of time of the packet, T_guardIs k _guard It is time for sample length. K_gateLong digitized data frames
The output from each ADC is then applied to a sparse FFT 328 with window zeros embedded.
Which is the packet, where each tone is divided by the integer number of the FFT bin
Convert to frequency domain.

The FFT bins are sent to a demultiplexer 330, which converts any unused FFTs
The bins are removed from the received data set and the remaining bins are sent to each transmitted bin.
K containing tones received over the pred cell_cell× (K_spread・ K _array ) Group into a data matrix, where K_spreadIs the frequency spread
Coefficient, and K_cellIs the symbol per data cell pre-spread
The number, K_arrayIs the number of antennas. Each splitter red data cell is
Passes a bank of linear combiners 332 that eliminates co-channel interference covering the cell
And decodes the original baseband symbol tones from the received data set.
Spread. The weight of each combiner is code-gated self-coherence recovery
Adapted using a method that simultaneously despreads the received data signals.
Frequency dependent multi-antenna reception and spatial filtering of the spread signal in question.
Do the waves.

The combiner weights are used to construct a set of transmit weights used in any subsequent feedback transmission. Such tones are then sent to a delay and Doppler equalizer 334, which evaluates and removes Doppler shifts (non-integer FFT bin shifts) and message propagation delays (phase presence) from the received data set. Symbol demodulator 336 evaluates the transmitted message symbols.

As a result, the received data packets transmitted from each user are despread and extracted from the received interference environment. The processor does not require precise timing / carrier synchronization to the transmitter until after the baseband signal is despread with a high signal-to-jam and noise ratio in the presence of strong noise and co-channel interference.

[0068] K _cell symbols transmitted from user m is weighted each K _{cel l} tones received at frequency cell k, weighted by the antenna 1 identical complex despreading weights w _kl (m), then each tone Of cells together, so that the tone q of each received frequency cell is used for all K _spread ·
It is extracted from the receiver channel by summing the K _array frequency cells and antennas.

Each multi-element transceiver has a minimum number of combined spatial and spectral degrees of freedom of K _array K _spread to properly neutralize unstacked carrier interferers that penetrate each frequency cell. It is preferred to have. The excess remaining degrees of freedom are used to improve the SINR of the despread baseband signal or to separate overlapping stack carrier signals. The multi-element despreader weight is then adjusted to maximize the power of the despread baseband signal. This results in a code nulling scheme that is significantly more powerful than the normal despreading method. An ideal despreader adjusts the despread weight to a null, unstacked carrier interferer up to the noise floor across each frequency cell, while enhancing the SINR of the despread signal. The multi-element despreader preferably introduces a very weak null for interferers with weaker radio signals in a given frequency cell. Soft nulls can therefore be introduced at interferers received at a lower frequency cell at a given frequency cell. If the interferer spectrum has particularly weak values at these frequencies, for example, weaker nulls can be introduced at the far end edge of the passband of the interferer.

Despreader weights, typically including adaptive antenna arrays, significantly improve the quality and capability of signal transmission and reception operations. On the receiver side of the system, blind or uncalibrated methods can be used to steer a near-optimal beam in the signal of interest, while simultaneously steer nulls in the signal with jamming.

Typically, the despread weight is adjusted to maximize the despread baseband signal, eg, the signal to interference and noise ratio (SINR) of the estimated data symbol. This typically results in a set of code null despread weights that is very different from the spread gain used to spread the baseband signal at the other end of the link. In particular, such resulting despread weighting simultaneously removes channel distortions such as selective gain and fading caused by multipath. Despreading provides the best compromise between null interference received by the transceiver by maximizing the signal to interference ratio and maximizing the signal to noise ratio (SNR) of the despreader. The despread code of a typical DSSS and CDMA communication system is set equal to the spread code of the other tamper of the link and only maximizes the SNR of the despread baseband signal.

Such an operation is performed blindly in the preferred embodiment of the present invention, and the transmission spread gain and channel distortion are not known in the despreader. This simplifies the protocols used in the network by allowing the use of unknown spread gain of transceivers in the network. This also allows for adaptive determination of spread gain that is continuously optimized to mitigate noise, interference, and channel distortion encountered by the transceiver during the course of transmission.

Such a method uses a multi-element S using an antenna array by not requiring spread, despread or quality changes of the gain / weight adaptation algorithm.
Provides upgrade to CMA or SCSS transceiver. The difference is the multi-element transceiver in the range of multi-element spread and despread operation. However, multi-element transceivers have greater capacity due to the greater degree of freedom that can be used to separate SCSS signals. Insensitivity to range and / or blockage by radiometer detection means is increased due to the ability to steer spatial beams at other communicators in the network. The insensitivity to jamming from non-SCSS signals is also improved due to the ability to spatially null such signals, even if they arrive over a wide frequency range.

A rapid convergence method that works over one data packet can also be combined with the frequency channelization signal or processor structure of interest, thereby eliminating the need for array calibration data or the signal of interest or interferer signal Allows the frequency selective nulling of the interferer signal without having to know or evaluate the direction of arrival of the interference signal. Therefore, the system 10 (FIG. 1) can detect and demodulate data packets in a high dynamic environment where the channel shape varies greatly between packets.
In this way, the processor can operate in a typical overloaded environment where the number of interferences is not less than the number of antennas in the antenna array of the receiver.

On the transmitter side of the system, a directional or retrodirective adaptation method
To guide the signal of interest back to the source with the highest power and / or the lowest transmitted radio signal (directional mode) or to send the signal of interest back to the source with the lowest emission in the direction of the interferer Used to guide (retrodirective mode).

The directional mode is useful in applications where contention with non-SCSS interference is not a major issue for the communicator or where the interfering transmitting and receiving platforms are unlikely to be co-located. This mode also has a non-SCS heavy communication platform
It is also useful in applications where no S interference is present, so that the maximum power must be transferred to the other end of the communication link.

Even if the interferer completely covers the pass band and the packet interval of the signal in question, the processor can accurately determine the steering vector of the received signal in question without knowing the direction of arrival of the signal in question. And can be used to guide the largest beam back to the other end of the communication link. The system 10 (FIG. 1) preferably transfers a higher power coefficient _Karray to the other end of the communication link, giving the system additional immunity to jamming. This can be achieved even if the other end of the communication link is transmitting and receiving by one antenna. Conversely, the system 10 (FIG. 1) can maintain a communication link by using the coefficient K _{arra y} of smaller power. This reduces the geographic area where the other party can detect the system by the coefficient _Karray .

The retro-directive mode implemented in FIGS. 6A and 6B as retro-adapters 136 and 148 can be used, for example, when the eavesdropper is co-located with the interferer to assess the effect of the jamming method. It is effective in application. This method is most effective in underload environments where broadband nulls can be induced at the interferer.

FIG. 14 shows one frame digital multitone (DMT) modulation and spread format 340. Format 340 is used in one example environment where K _cell = 6 and K _spread = 4, where each spread cell is divided by two FFT bins. The six data bits transmitted are first converted to a set of ± 1 data symbols. Symbol by separate complex weighted g _k in each cell, urges four cells of FFT bins, for example, six baseband FFT bins that are replicated in spread cells. The complex weight is the spread gain and is set randomly or pseudo-randomly for each data packet. Spreading is performed in the frequency domain by multiplying the time domain representation of the baseband signal by a set of superimposed or stacked complex sine carriers. In practice, the spreading is done by simply energizing the bins of the large FFT, saving considerable computational complexity of the output FFT size. The β = 9 Kaiser Bessel window is
In the present invention, these tones are used to "fill" the space between tones without causing unacceptable interference from neighboring tones, such as inter-tone interference. In particular,
A high value of β gives acceptable interference between adjacent tones and very low interference on the farthest tone.

Non-blind or calibrated techniques use baseband data sequences or knowledge of channel distortion and spread gain, thereby providing ideal weighting based on optimal signal estimation methods such as, for example, least squares techniques. Generate
Blind or uncalibrated techniques use more general properties of the baseband data signal to accommodate despread weighting. Combinations of these techniques that use known or unknown components of the baseband signal and / or the transmission channel are also used or constitute an effective solution. Examples of particularly useful blind techniques include constant coefficient, multiple coefficient and decision direction techniques. These adapt to despread weighting using the properties of the message symbol constellation. Several methods can also be used in the demodulator 332 to adapt the multi-element despreader weight (FIG. 13). First, there is a fundamental mode prediction (DMP) method that utilizes a known packet arrival time or a known spread parameter of a discrete multitone stack carrier signal. Second, there is a code-gated self-coherence recovery (SCORE) method, which eliminates the zero between spectrally separated signal components in a known self-coherent or discrete multi-tone stack carrier signal. Take advantage of no correlation.

[0081] Of these two basic types of methods, the self-coherent recovery technique has the greatest effectiveness in capturing and detecting one packet of a discrete multi-tone stack carrier signal.

[0082] Regular spectrum and other types of self-coherent recovery utilize known spectral and / or conjugate self-coherence properties. This is a non-zero correlation between the frequency shifted and / or conjugate components of a given communication signal. The blind method does not require prior knowledge of the signal contents in question or their direction of arrival. Thus, no particular receiver calibration information is needed to train the receiver antenna array. Instead, the blind method uses its own local information about the particular frequency shift to which the signal in question is correlated. “Self-Coherence Restoral: A New App by B. Agee. S. Schell and W. Gardner
roach to Blind Adaptation of Antenna Arrays ”, Proceedings of Twenty-Fi
See rst Asilomar Conference on Signals, Systems and Computer 1987. See also B. Agee. S. Schell and W. Gardner's “Self-Coherence Restoral: AN
ew Approach to Blind Adaptive Signal Extraction Using Antenna Arrays ”,
See IEEE Proceedings, No. 4, pp. 753-767, April 1990. B. A
gee's “The Property Restoral Approach to Blind Adaptive Signal Extracti
on ", Ph.D. Dissertation, University of California, Davis CA, 1989.

For a dual sideband amplitude modulated signal, the actual IF representation of any such signal is the dual sideband amplitude modulated signal format and DC and both for the actual IF representation. It has conjugate symmetry about the carrier frequency. These symmetries offset each other, making the negative and positive frequency components of the signal equal to each other. This perfect spectral self-coherence is observed by calculating the correlation coefficient between the dual sideband amplitude modulated signal of interest and a replica of that signal frequency shifted by twice the carrier. . The frequency shift operator mixes the negative frequency component into the frequency band occupied by the positive frequency component, causing the correlation coefficient to have a non-zero value.
Such non-zero values only occur when this frequency shift value is provided to the replica. The correlation coefficient is smaller than 1 in this example. A correlation coefficient of 1 is obtained by filtering the external overlapped radio signal of interest in the original and frequency shifted double sideband amplitude modulated signal.

In FIG. 15, a cross self-coherence recovery (SCORE) processor 350 is used to perform the recovery, which is provided to the multi-antenna received data signal x (t). Processor 350 first filters the received data with a series of filters, frequency shifts, and processes the data with a selective conjugation operator to generate signal u (t) that is only correlated by the processor with the target signal. Let it. The original signal and the processed signal x (t) = u (t) are then combined with the combiner output signal y (t) =
A pair of beam and null steering devices (linear element combiners) configured to maximize the correlation coefficient between w "x (t) and r (t) = c" u (t) ) Pass 352 and 354. The control parameters used to target the processor are:
A filter operator, a frequency shift value α, and a conjugate flag (*) typically set for the delay operator. The processor parameter is set to a value that produces a strong correlation coefficient, for example, when there is no interference when transmitting the signal of interest to the processor.

FIGS. 16 and 17 show the code gate operation used in the normal code gate SCORE operation. Certain code gate structures require some significant modifications to the spreader and despreader data streams, and therefore to the structure, which are one way to enable the code gate SCORE despreader adaptation algorithm described herein. Is shown. There are other ways to apply a code gate that traverses a packet or embeds a frequency cell, rather than traversing a frequency cell. For example, repeating data symbols with a gate code provided across K _cell baseband symbols over an even number of packets does not result in affecting the data flow through spreaders and despreaders. Partition the spread cells into K _part ≧ 2 subsets, K _SCORE cells / subset. −K _part = K _spread , cells processed in individual subsets K _SCORE = 1 cell / subset −K _part = 2, cells separated into even and odd subsets K _SCORE = K _spread / 2 cells / subset In each case The same code key is used for each cell of -K _part · K _SCORE = K _spread · subset. −c (n; K _part / + k) = c (n; k), k = 0,..., K _part −1, / = 0.
, K _SCORE ^-1 _-Another form: c (n; k) = c (n.; (K) K _part ), k = 0,..., K _spread ^-1 , (k) Modulo of K _part = k- K _part multiple SCSs using different code keys having the same structure in each subchannel
Transmit over S subchannels (stack carrier multiple access). -Enables separation of K _array K _SCORE SCSS subchannels per subset (code executed-null). -Enable higher data rates per user (multiple sub-channels per user). -Enable multiple access communication (multiple users communicating with the cell). -K _SCORE ^-1 Enable elimination of SCSS interferers (cellular communications). -Requires higher time-bandwidth products to obtain the same misadjustment level. _-In fact, the K _part is adjusted for special applications. K _part = Asynchronous point-to-point link, K _{spre ad} in a cellular overlay system where non-SCSS interference is high and high speed computer _convergence time is important 1 for point-to-multipoint link and high SCSS interference K _{pa rt} = 2 for point-to-multipoint links.

Code-gated self-coherence recovery is a technique that deliberately adds self-coherence information that is added by the communication system to facilitate compatibility spreaders and cannot be recognized without accessing the gating information of the communication network. Use. The two code gate SCORE methods are not included in the present invention.

A preferred self-coherence recovery method for multiple access communication involves applying a unique code gating operation to the baseband message signal before the spread operation, which is uniquely determined at each link of the system. . For example, frequency cells are separated into two subsets of cells, even and odd, and only odd cells are given a code key as represented in FIGS. Data symbols are spread in even cells using the method shown in FIG. 12 and the associated text.

A similar spread operation can be provided for an odd number of cells. However, the data symbols transmitted in these cells initially undergo a code gating operation in which they are multiplied by a constant coefficient code key c (m) = [c ₄ (m)] that is different for each user in the network. . This operation is the opposite for a multiple access despreader. After the despreading operation, but before combining the despreader outputs used in the even and odd frequency cells, the odd frequency cells have the code key c ^* (m
). With a single user (SCSS) transceiver, the code gating operation is performed with only one code key used by the SCSS transceiver. During a single packet capture operation, the despread (conjugated) code key is provided to each odd received frequency cell and each transceiver antenna, ie, prior to the linear combination operation.

The effect of the code gating operation is that after the odd frequency cells have been multiplied by the despread code key, the signal transmitted with that code key has a correlation coefficient of 1 between the even and odd frequency cells. It is. Conversely, the same code gating operation causes all other signals transmitted using different code keys to have a low correlation coefficient between even and odd frequency cells. This state is maintained regardless of the (assumed unknown) delay and Doppler shift added to the received signal. The resulting signal can then be input directly to the cross SCORE algorithm shown in FIG. 15, where x (t) is replaced by an even (uncated) frequency cell and u (t ) Is replaced by an odd (gated) frequency cell, where t is the symbol index q = 1,.
, K _cell . The despread weights are adapted to maximize the correlation coefficient between the outputs of the despread linear combiner applied to the even and odd frequency cells.

With such a method, unambiguous detection and despreading of an arbitrary link in the network is performed based only on the code key known for the link. In a single-user SCSS transceiver, the transceiver acquires the link and only requires the link over which it is communicating without requiring additional action to ensure that it is transmitting the correct signal. To despread.
A link is a "port shuffling" that occurs, for example, for long transmissions
In the event of temporary loss due to harmful channel conditions such as, etc., it is automatically reacquired. In a multi-user SCMA transceiver, this method allows unambiguous detection, de-sampling based on only the known code key used by the node linked to the transceiver without causing port swapping or shuffling when the channel conditions change. The spread and any links supported by the transceiver can be identified. The code key provides some confidentiality due to the scrambling included in the code gating operation.

The basic code-gated SCORE method can also be generalized in a number of ways. In particular, code keys may be applied to even and odd frequencies to provide increased security and de-correlation between frequency cells. Code gating may also be applied to time instead of frequency by transmitting data symbols on successive packets, code gating is not performed during even packets, and is applied to all frequency cells during odd packets. It is done for. If the spreading code is kept constant for these packet pairs, this method allows a more powerful auto SCORE method to be used to accommodate the despread weight. * More powerful algorithms enabled in some environments-Channel response characteristics are approximated as being identical or nearly identical (different complex scalar) on each spreading subset-Background interference is identical on each spreading subset * Maximum likelihood estimator-The spreading gain is forced to be the same or almost the same on each spreading subset-The despread weight is forced to be the same or almost the same on each spreading subset Despread weights are set to the main mode of the Auto SCORE eigen equation * Advantage over cross SCORE eigen equation * Low complexity * Low misalignment at the same time-bandwidth product Forced Maximum SINRs in GIS: Possible Asymptotic Misadjustment No * Some disadvantages • If the channel response characteristics are not exactly equal on each subset, it is sensitive to modeling errors and requires timing and / or Doppler tracking / removal during despread operation (algorithm Is generally very simple).

A very large number of frequency or packet subsets may also be used in the system, with a separate set of code keys being used for each subset. In this case, the despreader uses a generalization of the cross SCORE method obtained from supervector analysis of the cross SCORE eigen equation. Literature (B. Agee, “The Prop
erty-Restoral Approach to Blind Adaptive Signal Extraction, ”in Proc. 19
89 CSI-ARO Workshop on Advanced Topics in Communications, May 1989, Ruidos
o, NM and B. Agee, “The Property Restoral Approach to Blind Adaptive Sig
nal Extraction, ”Ph.D.Dissertation, University of California, Davis, CA, J
l2_systemmessage [1989] As the number of frequency subsets increases, the number of multiple access communications that can be supported by the transceiver decreases, but the stability of the weighted computations improves, the noise reduction of the algorithm and the ability to nullify non-stacked carriers increase. Remains unchanged. The limit on the number of frequency subsets is equal to the spreading factor K _spread .

The code-gated self-coherence recovery method uses the principal mode of the multi-cell self-coherence recovery eigen equation to extract the baseband of the signal of interest directly from the channelized data supervector. At the same time, the method performs frequency-dependent spatial filtering, combines the antenna elements in each cell for important spreading signals, and despreads the resulting data signal to combine the frequency cells.

The code-gated self-coherence recovery method works efficiently with positive and negative received SINR as long as the maximum achievable despread of the received data packets and the beamformed SINR are positive be able to. This method fits the antenna array as an intrinsic component of the despreading linear combination operator. The same method is used for any number of antennas, including a single antenna system where K _array = 1. The code-gated self-coherent recovery method does not require any prior knowledge of the spreading gain or the underlying message sequence at any point in implementing this. In this way, no search for time or Doppler shift frequency is required to despread the message sequence.

The main eigenvalues of the code-gated self-coherent reconstructed eigen equation detect a new signal packet when the communication link is first put into operation. The receiver works on an "on demand" basis, returning pulses to another end when a packet is transmitted on the communication channel.

According to an additional method, the detection of discrete multi-tone stack carrier data packets is enhanced or confirmed after code-gated self-coherence restoration. In particular, the reliability of detection is significantly enhanced by using fewer eigenvalues of the code-gated self-coherent reconstructed eigen equation to predict the mean and standard deviation of the maximum code-gated self-coherent reconstructed eigenvalue. Can be Thereafter, the true maximum eigenvalue is decremented by the predicted average and scaled by the predicted standard deviation, resulting in a much stronger trend of corrected detection statistics.

Another method uses downstream despread and demodulation operators to confirm packet detection during code-gated self-coherent recovery.

The first Doppler regeneration during the acquisition of the first data packet is performed at the reception position FFT
, Using the frequency domain analog of a fractionally spaced equalizer by extracting the first data packet in all remote modes and resampling the resulting output signal to the transmit position frequency remote mode using a linear interpolation method. The linear combination weight is
The data is resampled to the center of the tone using some suitable adaptation method. A least-squares property restoration algorithm, such as a constant modulus method, minimizes changes in the coefficients of the despread data symbols. The least-squares-constant method takes advantage of the property that transmitted data tones have a constant if they are generated using the BPSK modulation format, but the property that the transmitted signal is a non-integer number of tone intervals. Destroyed if exposed to double Doppler shift. The least squares constant method restores this characteristic to the output signal of the despreader. The entire technique operates when there is significant Doppler shift and path delay. Literature (B. Agee, “The Least-Squares CMA: A New Approach to Rapid Corr
ection of Constant Modulus Signal, ”in Proc. 1986. International Conferenc
e on Acoustics, Speech and Signal Processing, Vol.2.pg.19.2.1, April 1986.T
okyo, Japan).

Two general methods are valid for generating antenna array weights for data transmission. Retro directional transmission makes the transmission weight proportional to the conjugate reception weight, and directional mode makes the transmission weight proportional to the conjugate packet steering vector. The retro directional mode is well suited for commercial and military inflight communications where the interfering signal may be another member in a multipoint communications network.

Directional mode is most useful in applications where the covert nature is of primary importance to the caller, and the jamming and intercept platforms are probably not co-located. This mode is useful in applications where the communication platform is exposed to heavy interference, so that the other end of the communication link must be given maximum power to communicate in the presence of interfering wireless radiants. However, this method does not have the attractive property of guiding energy from another interference in a communication network.

The directional mode also constitutes a multiplier adaptation strategy that can greatly simplify the complexity of the despreader when larger spread spectrum coefficients are used for the wireless link.

Here, the retro directional transmission mode will be described. Retro directional mode
Set the transmitter antenna array weight equal to the conjugate array weight calculated during signal reception. If the transmit and receive operators are performed on the same frequency band and any internal differences between the transmit and receive paths are equalized, the transmitter antenna array will
It has the same gain pattern as the antenna array for the receiver. The transmitter antenna array evaluates the null direction in the direction of any interference that was present during signal reception. The null depth to be used for each is determined by the relative strength of the received interference.

Here, consistently, g _k is a dimension vector of K _array × 1,
Represents the multi-element spreading vector used in transmission for frequency cell "k". The multi-element spreading vector used at the receiver for frequency cell "k" is denoted by w _k , which is also a K _array × 1 dimension vector.

Embodiments of the present invention provide frequency selective transmission weights by spreading the transmitted packets using a different set of K _array × 1 spreading (g _k ) weights for each spreading cell. It is preferable that it is comprised as follows. This is (multi-element)
By making the spreading gain g _k proportional to the spreading weight w _k of the K _array × 1 linear combiner used for each frequency cell during signal reception such that g _k = λw _k , Determine the frequency selective retro directional transmission weight. This mode is especially effective in environments dominated by wideband interference sources, since the resulting null depth is limited by the antenna array dispersion realized for each frequency cell. In this case, the processor nulls the interference source for frequency and space. The transmitter antenna array nulls only its respective interference source for the frequency cells occupied by the interference source. While this is excellent for receiving important signal packets, it is not useful for transmitting packets if the aim is to guide the packet radio signal from the location of the interference source through the entire packet passband. Such an objective cannot be satisfied by any means when the number of partial band interference sources is equal to or greater than the number of elements of the antenna array.

In the directional transmission mode, the antenna array weight of the transmitter is (conjugate) K _array ×
It is made equal to one packet steering vector. If the transmitting and receiving operators are on the same frequency band and the differences between the transmitting and receiving paths through the transmit / receive switch are approximately equal, the resulting antenna array will have the maximum wireless energy at the other end of the communication link. Guide or close the link with minimal transmitted radio energy. Directional arrays generally ignore the location of the interfering source, for example, it implicitly assumes that interception is somewhere in the field of view of the communication link.

In the present invention, the directivity method can be implemented on a frequency selective basis.
This offers certain benefits in wideband communication links, exceptionally for example for large values of K _spread or for highly dispersive communication channels where the packet steering vector varies significantly with respect to the packet passband. be able to. However, this is not important because the maximum power mode is strongly degraded by minor errors in the packet steering vector.

Such estimation errors are likely to be large if the communication link is severely jammed, or if the packet steering vector has to be estimated for a short communication interval, eg, a single packet. In particular,
For an overly simple method, a directional transmit antenna array directs a beam of high transmit energy to an interference source in its environment. The directional transmission method or packet steering vector estimation is simple enough to implement inexpensively, but sophisticated enough to operate reliably under the expected jamming range and transmission scenarios There is a need.

[0108] Three general steering vector estimation methods are preferred. The first one is
A correlation method for estimating a packet steering vector using a correlation between received packet data and estimated packet data. The second is a multi-cell ML-like method for estimating packet steering vectors using maximum likelihood (ML) estimators obtained in the presence of frequency channelized (multi-cell) data under appropriate simplification conditions. The third is a parametric method that further refines the multi-cell estimator by constraining the packet steering vector using an appropriate parameter model.

The correlation method is the simplest of the three packet steering vector estimation methods. The disadvantage of this method is realized by considering the estimates obtained in the presence of a single interference source, which estimate is based on the packet steering vector, plus the difference between the received interference source and the packet signal. The cross-correlation reduces the scaled interference source steering vector. The time-bandwidth product (samples) required to reduce this cross-correlation to zero is much larger than 1 / S of the interfering source signal if the interfering source is 50 dB stronger than the packet signal,
For example, 1,000,000 samples. Therefore, this method is usually inappropriate.

The other two methods can overcome this limitation by using an optimal maximum likelihood (ML) estimation procedure to estimate the packet steering vector. This resulting estimate provides accurate steering vector estimates in the presence of wideband or sub-band interference sources using simple (non-parametric) or sophisticated (parameter) steering vector models. further,
The nature of these estimates is usually predictable using the Kramer-Lao limit analysis.

[0111] Effective performance limits are based on any non-parametric data obtained in a multi-cell environment.
Derived for the tearing vector estimate. The received data is an unknown complex
Scaled by a number of steering vectors and by additive complex Gaussian interference
K each containing a degraded known (or estimated) packet baseband _spread Are divided into individual frequency cells. The steering vector in the Pe cell is
, A_k= G_kmodeled by a, where "a" is a (frequency independent) packet
The steering vector, g_kIs a scalar reception for the kth diffusion cell
Single antenna packet spreading gain. Complex Gaussian interference is monotonous between cells.
And mean zero and unknown autocorrelation matrix in the kth cell.
Cousin:

(Equation 1)

Is assumed to be a temporary white with

[0113] Packet steering vector a is assumed to be arbitrary complex dimension K _array vector of dimension K _array, for example a is any parameterized model set (e.g., parameterized with respect to azimuth and elevation Array Manifold) is not constrained to stick. The steering vector estimate generated using this model is, for example, a non-parametric technique. Literature (H. Van Trees, Detection, Estimation, and Modulation Theory, Part
I, New York: Wiley, 1968). By using the Cramer-Lao bound theory, the unbiased estimator of a has estimated accuracy (mean squared error) limited by the given Cramer-Lao bound. The matrix R is the interference autocorrelation matrix equal to the inverse of the averaged inverse autocorrelation matrix:

(Equation 2)

Is interpreted as the generalized “mean” of

In a preferred embodiment, the spatial steering vector a and the spread spectrum gain (g _k ) are calculated iteratively using the following formula:

(Equation 3)

Where [R] is the data autocorrelation matrix measured for the adaptive block in spectrum cell k and w _k is the despread weighted spatial component used in spectrum cell k. Steering vector and the spreading gain may be used to calculate also improved despread weights w _k, the despread weights w _k, the spatial processing spectral processing (linear combination with respect to frequency cell) is followed ( (A linear combination in each frequency cell).

The stacked carrier spread spectrum wireless communication device shown in FIGS. 1-15 in combination with a code nulling technique represents another embodiment of the present invention. Code nulling interference cancellation techniques can be effectively combined with stack carrier spread spectrum techniques. For more information on code nulling design, see the literature (Brian Agee
“Solving the Near-Far Problem: Exploitation of Spatial and Spectral Di
versity in Wireless Personal Communication Networks, ”Wireless Personal Communications, edited by Theodore S. Rappaport, et al., Kluwer Academic Pub
lishers, 1994, Ch. 7.). The literature (Sourour.el al., “Two
age Co-channel Interference Cancellation in Orthogonal Multi-Carrier CDM
A in a Frequency Selective Fading Channel, "IEEE PIMRC '94, pp.189-193)
Please refer to. Furthermore, the literature (Kondo .el al., “Multicarrier CDMA System w
ith Co-channel Interference Cancellation, "March 1994, IEEE, # 0-7803-1927
, pp. 1640-1644).

The basic stacked carrier spread spectrum wireless communication apparatus shown in FIGS. 1 to 15 may include, for example, space division multiple access (SDMA), frequency division multiple access (FDMA), and code division multiple access (CDMA). , Simultaneous independent channels may be combined in a multiple access form of the invention to separate them by space, frequency and / or code.

In the SDMA form, an antenna array that can be selectively guided in space is used, for example to set a minimum of two zones. Each transmitter and receiver pair in one zone includes only the other in that transmitter-receiver pair so that it excludes other pairs in another zone that indicate another multiple access channel. Tune the corresponding antenna array. An embodiment of the present invention provides a SDM
It is characterized by combining the A technology with the stack carrier spread spectrum technology. For details of the SDMA design, see the literature (Forssen. Et al., “Adaptive Antenna”.
Arrays for GSM900 / DSC1800, ”March 1994, IEEE, # 0-7803-1927, pp.605-609)
Please refer to. The literature (Talwar.el al., “Reception of Multiple co-Cha
nnel Digital Signals using Antenna Arrays with Applications to PCS, ”19
94, IEEE, # 0-7803-1825, pp. 790-794). Furthermore, the literature (Weis.el al., “A Novel Algorithm For Flexible Beam Formong for Adaptive Space Div
See ision Multiple Access Systems, "IEEE PIMRC '94, pp. 729a-729e". Combinations of CDMA with antenna arrays are described in the literature (Naguib. et al., "Perfor
mance of CDMA Cellular Networks With Base-Station Antenna Arrays: The
Downlink, "1994, IEEE, # 0-7803-1825, pp.795-799).
Literature (Xu. Et al., “Experimental Studies of Space-Division-Multiple-Access
Schemes for Spectral Efficient Wireless Communications, ”1994, IEEE, # 0-7
803-1825, pp. 800-804). Further literature (M. Tangemann, “Influenc
e the User Mobility on the Spectral Multiplex Gain of an Adaptive SDMA S
ystem, "IEEE. PIMRC '94, pp. 745-749).

In the FDMA mode, a large number of carrier subsets are used for each channel, for example, a minimum of two subsets each have a minimum of two frequency divers carriers to set up a minimum of two channels. Each transmitter and receiver pair in a zone tunes its corresponding carrier subset to reject another carrier subset indicating another multiple access channel. It is a feature of an embodiment of the present invention to combine FDMA technology with stack carrier spread spectrum technology.

In the CDMA scheme, several spreading and despread weights are used, one set for each channel. Such multiple access is used by navigation receivers in the Global Positioning System (GPS). It is a feature of embodiments of the present invention over the prior art that it combines the CDMA technique with the stacked carrier spread spectrum technique shown in FIGS. For more information on CDMA design in a multi-carrier environment, see the literature (Fettwe
is.et al., “On Multi-Carrier Code Division Access (MC-CDMA) Modem Design,
"1994 IEEE, # 0-7803-1927, pp. 1670-1674).
lva.el al., “Multicarrier Orthogonal CDMA Signals for Quasi-Synchronous
Communication Systems, ”IEEE Journal on Selected Areas in Communicatio
n, Vol. 12, No. 5, June 1994). The literature (Reiners.el al., “
Multicarrier Transmission Technique in Cellular Mobile Communications Sy
stems, “March 1994. IEEE, # 0-7803-1927, pp. 1645-1649.” Further reference (Yee.el al., “Multi-carrier CDMA in Indoor Wireless Radio Network”
ks, "IEEE Trans. Comm., Vol. E77-B, No. 7, July 1994, pp. 900-904). The use of CDMA in the presence of fading channels is described in the literature (Stef).
an.Kaiser, “On the Performance of Different Detection Techniques for OFD
M-CDMA in Fading Channels, ”Institute for Communication Technology, Germa
n Aerospace Research Establishment (DLR), Oberpfaffenhofen, Germany, 1994)
It is described in. The literature (Chandler.el al., “An ATM-CDMA Air Interfac
See e For Mobile Personal Communications, "IEEE PIMRC'94, pp. 110-113. This technique is further described in Chouly.
IEEE, # 0-7803-0917, pp.1723-1728).

The combination of multi-carrier CDAM and decorrelation interference cancellation is described in the literature (Bar-Ness.
er CDMA Communication System With Decorrelating Interference Canceller,
"IEEE PIMRC'94, pp. 184-188).

A multiple access method for stacked carrier spread spectrum wireless communication includes constructing a stacked carrier spread gain from a complex amplitude and phase gain of a complex sinusoidal curve for each of a plurality of discrete frequency channels at a transmitter. Then, at the transmitter, any narrowband baseband data is spread by a vector multiplier and an inverse frequency channelizer. The next step is to simultaneously transmit data from the transmitter after spreading with a stack carrier spreading gain for multiple discrete frequency channels. The receiver despreads the discrete frequency channels with the vector dot product linear combiner and frequency channelizer so that any narrowband baseband prespread data is reproduced with relatively little channel interference. The frequency channels may be distributed non-contiguously within multiple bands. Instead, transmission is performed such that the frequency channels overlap and include an orthogonal frequency division multiplexed modulation format. Alternatively, the data transmission is performed in packets, where the baseband data is spread, transmitted and despread in discrete packets in an orthogonal frequency division multiplexed base frequency channelizer structure.

[0124] Packets may overlap in time, may be contiguous, or may not be contiguous. A preferred embodiment sequentially transmits one or more packets after receiving one or more packets sequentially from the other end of the link. Sequential transmission and reception of a large number of packets can allow asymmetric communication by, for example, increasing the number of packets transferred in one direction from another, and can also cause, for example, inter-base station interference in cellular communication networks. The guard time between the transmission mode and the reception mode can be increased to overcome the problem.

The combination of discrete multi-tone orthogonal frequency division multiplexing and antenna array processing techniques with discrete multi-tone stack carrier and antenna array processing techniques exploits the non-dispersive nature of discrete multi-tone and discrete multi-tone stack carriers. it can. By eliminating the need to mitigate stationary or quasi-stationary linear dispersion ahead of the adaptive receiver (eg, due to front-end receiver imperfections, non-zero array apertures, and fixed multipath scatterers and reflectors), The performance of adaptive antenna arrays for applications requiring dynamic interference cancellation can be significantly improved. This is especially true for space division multiple access (S) for communicating between multiple users on the same frequency channel set.
It is useful in cellular point-to-multipoint communication networks, including DMA) topologies. That is, each spatial processor is directed to the interfering user in its cell (
(Potentially) deep nulls must be formed.

Code division multiple access (CDMA) transmits multiple signals over the same set of frequency channels using a linear, independent (typically orthogonal) set of spreading gains. These codes are separated at the despreader using appropriate combiner weights.

Direct sequence spread spectrum systems can benefit from space division multiple access multiple access, interference cancellation, and channel equalization capabilities (code nulling techniques). Code nulling is a modulation-on-symbol direct sequence spread spectrum (MOS-DSSS) or pulse-on-modulation direct sequence spread spectrum (MOP- DSSS) format. Code nulling may be advantageously combined with a stacked carrier modulation format, for example, to eliminate spectrally redundant interference in HF / VHF frequency hopping intercept systems. In the prior art, common frequency hopping intercept techniques, including code nulling interference cancellation, have been used on stack carrier signals that simulate a tropospheric scatter communication link. However, this technique is extended by the present invention to point-to-point and point-to-multipoint communications where the intended caller and interference includes a stacked carrier spread spectrum modulation format. For example, a blind adaptation method of the introduced data is further included to optimize the despreader based on known characteristics of the traffic and pilot data transferred by the communication system.

The present invention combines stack carrier spread spectrum based communication and code nulling based interference cancellation for communication systems with high capacity, high immunity to channel distortion and low dependence on correlation between spreading gains. You. Closeness to orthogonality is not required, and embodiments of the present invention are less sensitive to narrowband interference or other system member stack carrier spread spectrum signals. Such effects are optimized when code nulling based interference cancellation is combined in a stacked carrier spread spectrum communication network. In particular, a stack carrier spread spectrum communication link that includes code nulling-based interference cancellation can provide an equivalent modulation-on-symbol direct-sequence spread-spectrum system, given the same spreading gain and complexity of the code nulling device (linear combiner). Double the number of links can be supported.

The present invention combines code nulling based interference cancellation and introduction data methods used to accommodate despreaders in a network. Such a combination provides the system with significant advantages over competing methods for point-to-point and point-to-multipoint (multiple access) communications. Such a system may utilize the full time bandwidth product of the communication system, thereby reducing the time of despreader acquisition and tracking in the system. Such systems also despread and demodulate (blind spread characteristics) the intended stack carrier spread spectrum signal important to the despreader without the spread gain information contained in the signal transmitter. It simplifies or eliminates the code selection strategy used and allows the use of retro-directional techniques to optimize spreading gains based on communication channels and networks. Null-interfering (in-cell or out-of-cell) stack carrier spread spectrum signals are received by the despreader without any knowledge of the spreading gain or content of the interfering signal, thereby causing interference as well as signals important to the receiver. Also greatly improves the complexity of sequential (typically non-linear) methods that must be demodulated and re-modulated. Static linear channel dispersion, including dispersion effects induced in the system front end, is automatically compensated for without any information or actual estimation of the channel dispersion, thereby increasing the complexity of the despread method and system hardware. Decrease.

Code nulling covers a range of spatial processing techniques and facilitates the use of retro-directional transmission methods to significantly improve overall network performance and economy.

Combining code-nulling and spatial processing techniques with an adaptive antenna array for beam steering improves the range of conventional communications transceivers that are not. This combination can also increase the capacity of a multi-cell network by reducing the interference provided to neighboring cells. Null steering for interference cancellation improves communication network capacity by allowing dense packing. Dense packing is made possible by separating users in matching frequency cells in a space division multiple access topology. Antenna arrays may be used, for example, by increasing the dimensions of the code nulling device to combine spatial and time channels, such as in a MOS-DSSS system, or to combine spatial and frequency channels, such as in a stacked carrier spread spectrum system. By increasing the dimensions of the code nulling device, it can be combined with code nulling techniques in a simple manner.

With the stacked carrier spread spectrum modulation format, the despreader reduces the stack carrier spread spectrum spread gain as the number of spatial channels increases to keep the complexity of the code nulling device constant as a function of the number of antenna elements. It becomes possible to do. This achieves a constant introduction data receiver adaptation time. Linear complexity increases with the number of antennas and users on the communication link. Also, the spatial distribution of users decreases as the number of antenna beams increases.

An excellent communication mode is realized by a combination of the code nulling introduction data adaptive retro directional transmission technique and the stack carrier spread spectrum modulation. One point to one
Point and point-to-multipoint communication links increase user capacity, range, power, and / or economy, over all channel pre-emphasis methods.

[0134] Stack carrier spread spectrum and adaptive antenna array processing can be used, for example, in cellular stacks where the interference is likely to be another member signal in the network and the multi-element antenna array is mainly used at base stations in the network. Helps eliminate spatially coherent interference in carrier spread spectrum networks.

FIG. 18 shows an example of a time-frequency format of a time-division duplex communication system.

FIG. 19 shows an active tone format of a basic DMT modem.

FIG. 20 shows a transmission / reception calibration method. There are two separate modes for system calibration and compensation. The SCSS calibration signal injected into the receiver at the calibration switch measures the receiver path variance. The SCSS calibration signal sent by the transfer switch to the output receiver through the transmit modulator measures the combined transmit and receive path variance. The transmission path is obtained from the combined reception and transmission calibration data. Compensation is provided at the DSP back end by transmitting and processing the SCSS calibration waveform.

FIG. 21 is a schematic diagram of an integrated single antenna T / R and DMT modem (DMT based SCMA).

FIG. 22 shows a generic example single link code gated cross SCORE.
It is the schematic of a spreading | diffusion operation | movement. It is the preferred mode for single link processing. This allows the use of the cross SCORE algorithm with the fastest convergence time (lowest TBP). It is not affected by timing and Doppler offset. It can eliminate K _array interference in each cell with high reliability. It can separate the SCSS signal K _array. The drawback is that it cannot reliably separate the> K _array of SCSS signals (no code nulling) and it misadjusts the maximum SINR solution in highly frequency-variable environments.

FIG. 23 is an example of a single link code gated cross SCORE spreading operation for a cell subset of K _spread .

FIG. 24 shows a single link cross S for N _frame packets / adaptive frames.
It is an example of a CORE algorithm. Despreader weights are calculated from the principal modes of the multi-set cross SCORE eigen equation.

FIG. 25 is an example of a single adaptive frame autocorrelation statistical calculation.

FIG. 26 is an example of the cross SCORE eigen equation for the cell subset of K _spread . Despreader weights are calculated from the principal modes of the multi-set cross SCORE eigen equation.

FIG. 27 is an example of a code key generator for a cell subset of K _pari <K _spread .

FIG. 28 is an example of an equivalent code key applicator for a cell subset of K _pari <K _spread .

FIG. 29 is an example of a cross SCORE eigen equation for a subset of K _pari . Despreader weights are calculated from the principal modes of the multi-set cross SCORE eigen equation.

FIG. 30 is an example of a cross SCORE eigen equation for two cell subsets. Despreader weights are calculated from the principal modes of the multi-set cross SCORE eigen equation.

FIG. 31 is an example of a multi-link code gated cross SCORE spreader. It is an improved mode for multi-link processing. This allows adjustment of the cross SCORE convergence time for SCSS interference conditions. It is unaffected by timing and Doppler offset. It can eliminate K _array interference in each cell with high reliability. It is K _array
The K _score SCSS signal can be separated. The drawback is that it cannot separate SCSS signals with> K _array K _score with high reliability (incomplete code nulling), which makes a misadjustment on the maximum STAR solution in highly frequency-variable environments. It is.

FIG. 32 is an example of a single link code gated auto SCORE spreading operation with frequency and gating for two cell subsets. It is the preferred mode for highly mobile systems. It can separate K _array and K _score SCSS links. It is the non-SCS of the K _array in each cell
S interference can be eliminated. It is not affected by timing and Doppler offset. The drawback is that it cannot separate SCSS links with> _score , which requires (simple) timing tracking as part of the despread algorithm.

FIG. 33 is an example of a single link code gated auto SCORE spreading operation with frequency and gating for two cell subsets.

FIG. 34 is an example of an auto SCORE eigen equation by gating the frequency and two cell subsets.

FIG. 35 is an example of a single link code gated auto SCORE spread with gating over time and 1/2 rate redundant gates. It is the preferred mode for low mobility systems. It is SC of K _array and K _spread
SS links can be separated. It can remove the K- _array non-SCSS interference in each cell. It is not affected by timing and Doppler offset. A 3 dB SNR gain is provided at the despreader. Its disadvantage is that it cuts the capacity in half and requires (simple) Doppler tracking as part of the despread algorithm.

FIG. 36 is an example of a single link code gated auto SCORE spread with gating over time and rate 1/2 redundant gates.

In summary, adaptive antenna arrays can be used to increase network system capacity via beam steering, null steering, or combined beam and null steering. In the present invention, such null steering or combined beam and null steering techniques are combined with a DMT / OFDM frequency channelizer independent of the channelizer used as the SCSS spreader / despreader.

While the invention has been described in connection with the presently preferred embodiments, it should be understood that the disclosure is not to be construed as limiting. Those skilled in the art will recognize various changes and modifications from the above disclosure. It is therefore intended that the appended claims cover all such changes and modifications that fall within the scope of the invention.

[Brief description of the drawings]

FIG. 1 is a block diagram of a communication system configuration of the present invention in which several remote mobile units are spatially distributed near one or more central base stations.

FIG. 2 shows a stack carrier spread spectrum transmitter bank connected to an antenna array for a point-to-point transmitter and another antenna array stacked for a point-to-point receiver. 5 with an embodiment of the present invention connected to a network transmitter and a stack carrier multiple access transmitter bank connected to an antenna array, and another antenna array for the network receiver and a stack carrier multiple access receiver FIG. 11 is a block diagram showing another embodiment of the present invention connected to a bank.

FIG. 3 shows a stack carrier spread spectrum receiver connected to a time division duplexer for a point-to-point transmitter and another time-division duplexer for a point-to-point receiver. Another embodiment of the present invention connected to a network carrier and a stack carrier multiple access transmitter connected to a time division duplexer, and another time division duplexer to a network receiver having a stack carrier multiple access FIG. 6 is a block diagram showing another embodiment of the present invention connected to a receiver.

FIG. 4 shows a stack carrier spread spectrum transmitter connected to a code nulling device for a point-to-point transmitter, and another code carrier nulling device for a point-to-point receiver. Another embodiment of the present invention connected to a receiver, a stack carrier multiple access transmitter for a network transmitter connected to a code nulling device, and another code nulling device for a network receiver. FIG. 10 is a block diagram illustrating another embodiment of the present invention connected to a stacked carrier multiple access receiver.

FIG. 5 shows a stack carrier spread spectrum transmitter connected to a wide-separation frequency channelizer for a point-to-point transmitter and another wide-separation frequency channelizer for a point-to-point receiver. Another embodiment of the present invention connected to a receiver and a stack carrier multiple access transmitter for a network transmitter connected to a wide separation frequency channelizer and another wide separation frequency channelizer for a network receiver. FIG. 10 is a block diagram illustrating another embodiment of the present invention connected to a stacked carrier multiple access receiver.

FIG. 6 shows a stacked carrier spread spectrum transmitter bank connected to a synchronized time division duplexer bank connected to both an antenna array and a stacked carrier spread spectrum receiver bank for a point-to-point transceiver system; In another embodiment of the present invention where the adapter is under the control of a stack carrier spread spectrum transmitter bank, and for a network system the stack carrier multiple access transmitter bank has both an antenna array and a stack carrier multiple access receiver bank. FIG. 6 is a block diagram illustrating another embodiment of the present invention connected to a connected synchronized time division duplexer, with a rear adapter under the control of a stack carrier multiple access transmitter bank.

FIG. 7 is a functional block diagram of a stacked carrier spread spectrum transmitter similar to that shown in FIGS. 2A, 3A, 4A, 5A and 6A.

FIG. 8 is a functional block diagram of a stacked carrier spread spectrum receiver similar to that shown in FIGS. 2A, 3A, 4A, 5A and 6A.

FIG. 9 illustrates the potential of an antenna array to enable spatial discrimination between members of a communication system, where each functional transmitter and receiver line is a multiple channel supported by a basic stacked carrier spread spectrum communication medium. FIG. 2 is a block diagram of a base station included in the system of FIG. 1 represented as including:

FIG. 10 is a block diagram of an exemplary remote unit included in the system of FIG. 1, illustrating adaptive channel equalization and pre-emphasis functions supported by a basic stacked carrier spread spectrum communication medium.

FIG. 11 is a block diagram of a multi-element T / R module including a plurality of individual T / R modules, one for each antenna. The complexity of the system can be increased or decreased by the number of antennas. Analog-to-digital conversion (ADC) during reception operation
Spatial processing is performed after the process and before the digital-to-analog conversion (DAC) operation during the transmission operation. All spatial and spread spectrum operations are performed on digital data. All key frequencies and clock references in the system are derived from a common clock, such as a GPS clock. A mechanism for module calibration required for accurate retro-directivity in a TDD system is shown.

FIG. 12 is a block of a stacked-carrier spread spectrum modulator in which baseband data is replicated for separate spread cells of K _spread multiplied by separate scalars passed to a time multiplexer to combine into a complex data vector. FIG.

FIG. 13 is a block diagram of an all-digital fully-adaptive stacked carrier spread spectrum despreader. The despreader includes several channels for processing each tone in a stacked carrier spread spectrum carrier medium.

FIG. 14 shows a data length of 6, a spread coefficient K _spread of 4, and a separation between groups of 2
FIG. 4 is an illustration of an exemplary BPSK multitone. Each group cell g1-g4 is represented as having independent amplitudes that can be manipulated by channel equalization and pre-emphasis to overcome interference and other problems.

FIG. 15: “S” used to recover the signal x (t) received from the antenna array
Schematic of the CORE "processor. The control of this processor includes a filter h (t)
, Frequency shift value α and conjugate control (*).

FIG. 16: Code-gated SCOR with gating on two cell subsets
FIG. 4 is a data flow diagram showing an E-spread operation.

FIG. 17 is a dataflow diagram illustrating a code-gated SCORE spreading operation with gating on two cell subsets, showing symmetry to that of FIG. 16;

FIG. 18 is a time-frequency format of a time division duplex communication system according to the present invention.

FIG. 19: Basic DMT modem active tone format.

FIG. 20 is a data flow diagram illustrating a transmission / reception calibration method.

FIG. 21 is a schematic diagram of an integrated single antenna T / R and DMT modem for implementing a discrete multitone (DMT) based Stacked Carrier Multiple Access (SCMA) system configuration of the present invention.

FIG. 22 is a schematic diagram of a general example of a single link code gated cross SCORE spreading configuration of the present invention.

FIG. 23: Single-link code-gated cross S for a cell subset of K _spread
The data flow figure showing CORE spreading | diffusion operation.

FIG. 24 is a dataflow diagram illustrating a single link cross SCORE algorithm for N _frame packets / adaptive frames.

FIG. 25 is a data flow diagram representing a single adaptive frame autocorrelation statistic calculation.

FIG. 26 is a data flow diagram showing a cross SCORE eigen equation for a cell subset of K _spread .

FIG. 27 is a data flow diagram illustrating a code key generator for a cell subset of K _pari <K _spread .

FIG. 28 is a data flow diagram _showing an equivalent code key applicator for a cell subset of K _pari <K _spread .

FIG. 29 is a data flow diagram representing a cross SCORE eigen equation for a subset of K _pari .

FIG. 30 is a data flow diagram representing a cross SCORE eigen equation for two cell subsets.

FIG. 31 is a dataflow diagram illustrating a multi-link code gated cross SCORE spreader configuration of the present invention.

FIG. 32 is a dataflow diagram illustrating a single link code gated auto SCORE spreading operation with gating for frequency and two cell subsets in one embodiment of the present invention.

FIG. 33 is a dataflow diagram illustrating a single link code gated auto SCORE spreading operation with frequency and gating for two cell subsets.

FIG. 34. Auto SCOR with gating for frequency and two cell subsets
FIG. 4 is a data flow diagram showing an E eigen equation.

FIG. 35 is a dataflow diagram illustrating code-gated auto-SCORE spreading of a single link with gating over time and rate 1/2 redundant gates.

FIG. 36 is a data flow diagram illustrating code-gated auto-SCORE spreading of a single link with gating over time and rate 1/2 redundancy gates.

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GE, GH, GM, HR, HU, ID, IL, IS, JP, KE, KG, KP , KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, ZWF terms (reference) 5K022 AA10 AA12 AA22 DD01 DD23 DD33 EE02 EE11 FF01 5K067 AA02 CC01 CC04 CC10 CC24 EE02 EE10 [Continuation of summary] The algorithm is used.

Claims (86)

[Claims] 1. One or more transmitters for transmitting a plurality of radio frequency (RF) carriers, and one or more radio receivers for receiving at least one subset of two or more of the plurality of radio frequency carriers. One or more spreaders connected to each transmitter and independently and redundantly modulating the amplitude and phase of two or more of the radio frequency carriers having a first digital spread gain and first data; One or more despreaders connected to a receiver and independently demodulating the amplitude and phase of two or more of the radio frequency carriers with a first digital spread gain to recover the first data; Machines, spreaders, and despreaders, and provide space division multiple access (SDMA), frequency division multiple access (FDMA), Multiple access communication system characterized in that it comprises a multiple-access means for separating the communication channels by at least one micro-code division multiple access (CDMA). 2. The SDMA further connected to the transmitter and receiver for selective data channel transmission and reception between a transmitter and receiver pair according to a relative spatial location. The system of claim 1, comprising an antenna array provided. 3. The FDMA further provides for two or more subsets of carriers for communication of additional data channels between a transmitter and receiver pair in accordance with matching of the subset of radio frequency carriers. The system of claim 1 including a minimum number of radio frequency carriers assigned. 4. The CDMA includes at least a second digital spread gain and a second data, wherein at least the first and second signals between a transmitter and receiver pair according to matching of a subset of the digital spread gain. The system according to claim 1, wherein the second communication is performed. 5. A radio transmission system for spatial and frequency dispersion, comprising a positive integer n individual antennas spatially distributed in a group, and also a spatial distribution of positive integers n. Antenna systems provided for the communication channels provided, and individual amplifiers connected to corresponding antennas of the antenna system,
A bank of radio frequency amplifiers, each amplifier being configured to control and steer a beam to provide zero-direction control of transmission of radio frequency signals over a radially spatially distributed communication channel; A discrete multi-tone stack carrier spread spectrum transmission modulator connected to a bank of amplifiers and provided for a plurality of frequency-dispersed communication channels, comprising: each output and a data input connected to the modulator; A spreader provided to jointly spread data across all of the plurality of frequency-dispersed communication channels; and a spreader connected to the bank of radio frequency amplifiers and radially distributed with a positive integer n. Operating means for selecting one of the spatial communication channels. Wireless transmission system. 6. The system of claim 5, further comprising: the system is polarization-dispersed, and the individual antennas are further polarized. 7. A radio receiving system for performing spatial and frequency dispersion, comprising: a positive integer n individual antennas spatially distributed in a group; An antenna system provided for communication channels distributed in, and an individual amplifier connected to a corresponding antenna of the antenna system,
A bank of radio frequency amplifiers, each amplifier being configured to control and steer a beam to provide zero control of the transmission of radio frequency signals over a radially spatially distributed communication channel; A discrete multi-tone stack carrier spread spectrum demodulator connected to a bank and provided for a plurality of frequency-dispersed communication channels, comprising: each input connected to the demodulator; and a data output, A despreader provided to despread the data contained across all of the plurality of frequency-dispersed communication channels; and a despreader connected to the bank of radio frequency amplifiers and radially spatially with a positive integer n. Operating means for selecting one of the distributed communication channels. Radio frequency receiver system. 8. The system of claim 6, further comprising calculating means for determining an address of a communication channel that is spatially distributed radially of the target receiver. 9. A multiple access method for stack carrier spread spectrum radio frequency communication, comprising: at a transmitter, a stack carrier from a complex amplitude and phase gain of a complex sinusoidal curve for each of a plurality of discrete frequency communication channels. Configuring a spread gain, spreading any narrowband baseband pre-spread data by a vector multiplier and an inverse frequency communication channelizer, and spreading said data after spreading over said plurality of discrete frequency communication channels by said stack carrier spread gain. Are simultaneously transmitted from the transmitter, and the plurality of discrete frequency communication channels are despread at a receiver by a vector inner product linear combiner and a frequency communication channelizer. , Multiple access methods the optional narrow-band baseband pre spread data, characterized in that it is played in the relative insensitivity to the communication channel interference. 10. The method of claim 9, wherein the configuration is such that the frequency communication channels are distributed non-adjacently in multiple bands. 11. The method of claim 10, wherein said simultaneous transmissions include overlapping frequency communication channels and an orthogonal frequency division multiplexed modulation format. 12. In the simultaneous transmission, the data is packetized, baseband data is spread, transmitted, and despread in discrete packets to an orthogonal frequency division multiplexed frequency communication channelizer structure. The method of claim 11, wherein the packets are temporally overlapped, contiguous, or non-contiguous. 13. A method for canceling interference in a stack carrier spread spectrum radio frequency communication, comprising: at a transmitter, determining a stack carrier spread from a complex amplitude and phase gain of a complex sine wave curve for each of a plurality of discrete frequency communication channels. Configuring a gain, spreading any narrowband baseband pre-spread data with a vector multiplier and an inverse frequency communication channelizer, and spreading the data after spreading over the plurality of discrete frequency communication channels with the stack carrier spread gain. Transmitting simultaneously from said transmitter, despreading said plurality of discrete frequency communication channels at a receiver by a vector inner product linear combiner and a frequency communication channelizer; Said narrowband baseband prespread data is reproduced with a relative insensitivity to communication channel interference, and the code is zeroed by means of interference cancellation according to the information obtained in the step of despreading. Erase method. 14. An adaptive antenna array method for stack carrier spread spectrum radio frequency communication, comprising: at a transmitter, determining a stack carrier from a complex amplitude and phase gain of a complex sinusoidal curve for each of a plurality of discrete frequency communication channels. Configuring a spread gain, spreading any narrowband baseband pre-spread data by a vector multiplier and an inverse frequency communication channelizer, and spreading said data after spreading over said plurality of discrete frequency communication channels by said stack carrier spread gain. Are simultaneously transmitted from the transmitter, and the plurality of discrete frequency communication channels are demultiplexed at a receiver by a vector inner product linear combiner and a frequency communication channelizer. The optional narrowband baseband pre-spread data is reproduced with relative insensitivity to communication channel interference, and multiple backplanes connected to the antenna array and the transmitter according to the despread baseband data. An adaptive antenna array method, comprising: adjusting a gain of an amplifier. 15. A time division duplex method for stack carrier spread spectrum radio frequency communication, comprising: transmitting a first plurality of discrete frequency communication channels to a remote receiver; Dividing the time into time slots reserved for receiving a plurality of discrete frequency communication channels, the complex number of a complex sinusoidal curve for at least one of the first or second plurality of discrete frequency communication channels; A stack carrier spread gain from an amplitude and phase gain is configured at the closest transmitter, and a vector multiplier and an inverse frequency communication channelizer are used to convert any narrowband baseband prespread data to the closest transmitter. Spread at Transmitting the data simultaneously from the closest transmitter after spreading over the first plurality of discrete frequency communication channels with a carrier spread gain; Despreading the second plurality of discrete frequency communication channels at a receiver, wherein the optional narrowband baseband pre-spread data is reproduced with relative insensitivity to communication channel interference; Controlling the time division step with accurate timing information obtained from a timing signal source available to both the close transmitter and both the long distance and the closest receiver. Time division duplex Law. 16. The method of claim 15, wherein said controlling comprises receiving system time information from an orbiting satellite. 17. A multi-tone transmitter array for transmission of a multispectral carrier signal according to a spatially weighted calculation by a computer for discriminating between a first plurality of individual remote receivers; And an antenna array for spatially adjusting the transmission power of the transmission of the multispectral carrier signal according to a spectrum weighted calculation by a computer for discriminating between the second plurality of individual remote receivers. A radio frequency transmission system, characterized in that: 18. A multi-tone receiver array for receiving a multi-spectral carrier signal according to a spectrum-weighted calculation by a computer for discriminating between a first plurality of individual remote transmitters, and connected to said receiver array. And an antenna array for spatially adjusting the received power of the reception of the multispectral carrier signal according to a spectrum weighted calculation by a computer for discriminating between the second plurality of individual remote transmitters. A radio frequency receiving system, characterized in that: 19. A multi-tone transmitter array for transmitting a multi-spectral carrier signal according to a spectrum-weighted calculation by a computer for discriminating between a first plurality of individual remote receivers, and connected to said transmitter array. A first antenna array for spatially adjusting the transmission power of the transmission of the multispectral carrier signal according to a spectrum weighted calculation by a computer for discriminating between a second plurality of individual remote receivers; A multi-tone receiver array for receiving a multi-spectral carrier signal according to a spectrum-weighted calculation by a computer that discriminates between a plurality of individual remote transmitters; a second plurality of receiver arrays connected to the receiver array; Multis following a spatially weighted computation by a computer to discriminate between individual remote transmitters. A radio frequency communication system, comprising: a second antenna array for spatially adjusting received power of reception of a spectrum carrier signal. 20. The system of claim 19, wherein a computer connected to the transmitter array and the first antenna array performs a single global computation of both spectral and spatial weights. 21. The system of claim 19, wherein a computer connected to the receiver array and the second antenna array performs a single global computation of both spectral and spatial weights. 22. A spectrum connected to the transmitter array, the receiver array, the first antenna array, and the second antenna array, and used by the receiver array and the second antenna array. A computer that performs a single global calculation of both weighting and spatial weighting, and both spectral weighting and spatial weighting used by the transmitter array and the first antenna array; The special spatial and spectral characteristics of the first and second plurality of individual remote transmitters are used to optimize the transmission back to the first and second plurality of individual remote receivers. 20. The system of claim 19. 23. The plurality of stacked carrier signals spread, modulated, transmitted over a wireless medium, and spread over each of the plurality of stacked carrier signals using different spread gains for each of the plurality of stacked carrier signals. A method of regenerating a digital communication signal received at a receiver as: Channelizing each of the received stack carrier signals to identify a baseband signal for each of the received stack carrier signals; The stacked carrier signals have a channel bandwidth that is separable from the channel bandwidth of the others, and apply a different despreading weight to the received baseband signal than the spread gain. The received baseband signal Generating a baseband signal that is despread by combination and compensated for interference to maximize the signal-to-noise ratio, and removing at least one of time distortion and frequency distortion present in the baseband signal. A method for reproducing a digital communication signal, wherein a reproduced digital communication signal corresponding to the digital communication signal is obtained. 24. The method of claim 23, wherein the step of despreading the blind despreads the plurality of received stacked carrier signals. 25. The method of claim 24, wherein said blind despread uses a dominant mode of generalized eigenforms. 26. The method of claim 25, wherein the blind despread uses a dominant mode of generalized eigenforms. 27. The method of claim 26, wherein said eigenform is a code that gates a self-coherent recovery eigenform. 28. The maximum code that gates the self-healing eigenvalue of the generalized eigenexpression is decremented by predicted means and scaled by the standard deviation predicted during the blind despread step. Item 29. The method according to Item 25. 29. The channelization, despreading, and removal steps are performed iteratively on each of a plurality of sequentially received stack carrier signals to obtain a reproduced plurality of related digital communication signals. 23. The method according to 23. 30. The method of claim 29, wherein the sequentially received plurality of stack carrier signals are asynchronous. 31. The plurality of sequentially received stack carrier signals are received during an associated time division duplex interval, and a network clock is used to determine the time division duplex interval.
The described method. 32. The method of claim 29, wherein the received time duplex interval is asymmetric with respect to the transmission of the time duplex interval. 33. The method of claim 31, wherein the received time duplex interval is symmetric with respect to the transmission of the time duplex interval. 34. The plurality of sequentially received stack carrier signals are received as a plurality of packets during a single time division duplex interval.
The method of claim 1. 35. The method of claim 31, wherein the plurality of sequentially received stack carrier signals are received as a single packet during a single time division duplex interval. 36. The method of claim 31, wherein said network clock is derived from universal time. 37. The method of claim 31, wherein said network clock is derived from data of said digital communication signal. 38. A second spread gain for a second data communication signal transmitted from the receiver as a second plurality of received stacked carrier signals, such that minimal radiation is guided at the interference frequency. 24. The method of claim 23, wherein the determination is made adaptively based on the despread weights. 39. The second spread gain is set in proportion to a conjugated and despread weight such that the gain pattern of the second plurality of received stacked carrier signals is 39. The method of claim 38, wherein the gain pattern of the received stack carrier signal is substantially the same. 40. A plurality of reproduced digital communication signals are simultaneously recovered from a plurality of received stack carrier signals, each of said plurality of digital communication signals determining each of said plurality of received stack carrier signals. 24. The method of claim 23, having an associated different code key used during said despreading step. 41. The method of claim 40, wherein each of the different code keys modulates only some of the plurality of received stack carrier signals. 42. The method of claim 41, wherein each of the different code keys modulates one of an even and an odd received stack carrier signal from the plurality of received stack carrier signals. 43. The method of claim 23, wherein the digital communication signal is a plurality of symbols, each symbol being modulated with a different discrete tone for each of the plurality of stacked carrier signals. 44. The method of claim 23, wherein the digital communication signal is a plurality of bits, each bit being modulated with a different discrete tone for each of the plurality of stacked carrier signals. 45. The method of claim 23, wherein said time distortion is due to Doppler frequency offset. 46. The method of claim 23, wherein said frequency distortion is due to time dispersion. 47. The method of claim 23, wherein said frequency distortion is a propagation delay. 48. The method of claim 23, wherein said removing step removes both time distortion and frequency. 49. The method of claim 48, wherein said time distortion is due to Doppler frequency offset. 50. The method of claim 48, wherein said frequency distortion is due to time dispersion. 51. The method of claim 48, wherein said frequency distortion is a propagation delay. 52. The method of claim 48, wherein said frequency distortion is a propagation delay. 53. The received stack carrier signal includes a guard time interval to compensate for unknown propagation delay and is not synchronized with the received stack carrier signal until the despreading step is completed. The described method. 54. The received stack carrier signal includes a guard frequency band to compensate for an unknown Doppler frequency offset and is not synchronized with the received stack carrier signal until the despreading step is completed. 23. The method according to 23. 55. A method for recovering a spread digital communication signal using spread gain when transmitted and received at a receiver, the method comprising despreading the received signal to generate a despread signal. A digital communication signal reproducing method comprising: removing a Doppler time delay from the despread signal to obtain a reproduced digital communication signal corresponding to the transmitted digital communication signal. 56. Regenerate a plurality of transmitted symbols spread using different spread gains, wherein the symbols are received at a receiver as a plurality of discrete multitones having substantially frequency diversity. A method of reproducing transmitted symbols, comprising: despreading each of the plurality of discrete multitones to generate a plurality of despread multitones, wherein each of the plurality of despread multitones is Corresponding to one of the transmitted symbols, removing the Doppler time delay from the despread multitone to obtain reproduced symbols corresponding to the transmitted symbols. The method of reproducing the characteristic symbol. 57. The transmitted symbols are spread and modulated for each of a plurality of stacked carrier signals using different spread gains for each of the plurality of stacked carrier signals, and 57. The method of claim 56, wherein each of the stacked carrier signals has a channel bandwidth, wherein the channel bandwidth is separated from a channel bandwidth of another one of the plurality of stacked carrier signals. 58. The method of claim 57, wherein the step of despreading the blind despreads the plurality of received stacked carrier signals. 59. The method of claim 58, wherein said blind despread uses one dominant mode of a generalized eigenform. 60. The method of claim 58, wherein said blind despread uses a plurality of dominant modes of a generalized eigenform. 61. The method of claim 60, wherein said eigenexpression is a code that gates a self-coherent recovery eigenexpression. 62. The maximum code that gates the self-healing eigenvalue of the generalized eigenform is decremented by predicted means and scaled by the standard deviation predicted during the blind despread step. 59. The method of claim 59. 63. Spectrally spreading a digital communication signal onto a plurality of stacked carrier signals to generate a plurality of spectrally spread digital communication signals, wherein each of the plurality of stacked carrier signals is a channel band. Having a width, the channel bandwidth of which is separable from the channel bandwidth of another one of the plurality of stacked carrier signals, and spectrally spreading each of the plurality of spectrally spread digital communication signals. Generating a plurality of spatially and spectrally spread digital communication signals, and wirelessly transmitting from each antenna element of the multi-element antenna array associated with each of the plurality of spatially and spectrally spread digital communication signals. Transmission to the receiver by Spread method of digital communication signal. 64. In a moving transmitter, digital information is spread using a different spread gain for each of a plurality of stacked carrier signals, wherein the plurality of stacked carrier signals reduce a channel bandwidth. Wherein the channel bandwidth is separable from the channel bandwidth of the other of the plurality of stacked carrier signals, and wherein each of the stacked carrier signals is wirelessly transmitted from the moving transmitter to the receiver. Transmitting the received plurality of stacked carrier signals as a stacked carrier received signal at a receiver, and receiving the received plurality of stacked carrier signals to identify a baseband signal for each of the stacked carrier received signals. Each of the stacked carrier signals Despreading by applying a despread weight different from the spread gain to each of the received baseband signals, combining each of the received baseband signals to compensate for interference, A digital communication method, comprising: generating a baseband signal having a maximum signal-to-noise and interference ratio; and processing the baseband signal to obtain reproduced digital information corresponding to the transmitted digital information. 65. The method of claim 64, wherein said processing step includes removing Doppler time delay from said baseband signal. 66. Each of the plurality of moving transmitters performs a step of spreading and transmitting the digital information, wherein each of the moving transmitters uses a different random non-orthogonal spread gain. And spread the digital information and spread the digital information on each of the plurality of stacked carrier signals. In the step of receiving the transmitted plurality of stacked carrier signals, the digital information is transmitted from each of the transmitters. Receiving the stacked carrier signal at a receiver, the step of channelizing channelizing each of the received stacked carrier signals, and the step of despreading comprises receiving the separately channelized reception. Each of the multiple stacked carrier signals Obtaining, for each of the plurality of transmitters, one baseband signal corresponding to the digital information transmitted by one of the plurality of transmitters, the processing step processing each of the baseband signals; 65. The method of claim 64, wherein said retrieving digital information corresponding to said transmitted digital information for each moving transmitter is obtained. 67. The method of claim 66, wherein said processing step includes removing Doppler time delay present in each of said baseband signals. 68. The method of claim 67, wherein said plurality of moving transmitters are geographically separated, each providing a different transmission path to said receiver. 69. A multi-element antenna array is used in said receiver, wherein different ones of said elements are used for different areas, and space division multiple access is used to identify different ones of said transmitters. 68. The method of claim 67 being used. 70. The method of claim 65, wherein frequency division multiple access is used to identify different ones of said transmitters. 71. The method of claim 67, wherein code division multiple access is used to identify different ones of said transmitters. 72. The method of claim 71, further comprising modulating different code keys for some of said plurality of stacked carrier signals associated with each said transmitter. 73. In a first station having a multi-element antenna array, spread digital information for each of a plurality of stacked carrier signals using different spread gains, wherein each of the stacked carrier signals is a channel. A bandwidth, the channel bandwidth of which is separable from the channel bandwidth of the other of the plurality of stacked carrier signals, wherein each antenna element transmits a different one of the stacked carrier signals. Transmitting each of the stacked carrier signals wirelessly from the first station to a second station at the second station using a second multi-element antenna array. Multiple stacked carrier signals And each antenna element of the second multi-element antenna array is used to receive a different one of the stacked carrier signals, a base for each of the stacked carrier received signals. Channelizing each of the stacked carrier received signals to identify a band signal; despreading by applying a despread weight different from the spread gain to each of the received baseband signals; A digital communication method comprising: combining baseband signals obtained as described above, compensating for interference, and obtaining a baseband signal having a maximum signal-to-noise and interference ratio. 74. A second spread gain for a second data communication signal transmitted from the second multi-element antenna array of the second station as a second plurality of stacked carrier signals, wherein the second spread gain is 74. The method of claim 73, wherein the minimum radiation at the jamming frequency is adaptively determined based on the spread weight. 75. The second spread gain is set in proportion to a conjugated despread weight, and a gain pattern of the second plurality of stacked carrier signals is a gain pattern of the plurality of stacked carrier signals. The method of claim 74, wherein the method is substantially the same as the gain pattern. 76. A second spread gain for a second data communication signal transmitted from the multi-element antenna array of the second station is adaptively determined such that maximum radiation is directed to the intended station. 74. The method of claim 73, wherein 77. The method of claim 76, wherein said second spread gain is determined adaptively using combined spatial and spectral vectors. 78. The method of claim 73, wherein the different spread gains associated with each of the plurality of stacked carrier signal gains are linear, independent, and non-orthogonal. 79. Spreading digital information for each of a plurality of stacked carrier signals using a different spread gain for each stacked carrier signal at a first station, wherein the plurality of stacked carrier signals are spread. Each of the carrier signals has a channel bandwidth, the channel bandwidth being separable from the channel bandwidth of the other of the plurality of stacked carrier signals, wherein each of the stacked carrier signals is wirelessly coupled to the second one. Transmitting from a first station to a second station, wherein the second station receives the transmitted plurality of stacked carrier signals as a stacked carrier receive signal using a multi-element antenna array; That of the stacked carrier received signal Channeling each of the stacked carrier received signals to identify a baseband signal for each; applying a despread weight different from the spread gain to each of the received baseband signals to despread; Combining each of the received baseband signals to compensate for interference to generate a baseband signal with a maximum signal-to-noise and interference ratio; and in the despreading step, spectral and spatial dimensions. Using a linear combiner dimension consisting of: 80. A second spread gain for a second data communication signal transmitted as a second plurality of stacked carrier signals from the multi-element antenna array of the second station, wherein the second spread gain is equal to the despread weight. 80. The method of claim 79, wherein the minimum radiation is determined adaptively based on the interference frequency. 81. The second spread gain is set in proportion to a conjugated despread weight, and the gain pattern of the second plurality of stacked carrier signals is the gain pattern of the plurality of stacked carrier signals. 81. The method of claim 80, wherein the method is substantially the same as the gain pattern. 82. A second spread gain for a second data communication signal transmitted from the multi-element antenna array of the second station is adaptively determined such that maximum radiation is directed to the intended station. 80. The method of claim 79, wherein the method is performed. 83. The method of claim 82, wherein said second spread gain is determined adaptively using combined spatial and spectral vectors. 84. The method of claim 79, wherein said spatial and spectral dimensions are variable for a plurality of different ones of said first station. 85. The method of claim 79, wherein said different spread gains associated with each of said plurality of stacked carrier signals are linear, independent and non-orthogonal. 86. A method for despreading a digital communication signal received at a receiver by radio, comprising: receiving a plurality of stacked carrier signals at each antenna element of a multi-element antenna array; Each of the signals has a channel bandwidth, the channel bandwidth being separable from the channel bandwidth of the other of the plurality of stacked carrier signals, and despreading the plurality of stacked carrier signals. Forming a spatially despread communication signal; and spectrally despreading the plurality of spatially despread communication signals, respectively, to form a spatially and spectrally despread digital communication signal. A digital communication method, comprising: