RU2354050C2 - Device and method for beams shaping in cdma communication system - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: invention is related to device and method for beams shaping in telecommunication system of mobile communication CDMA with application of intellectual antennas technology, using specified device and method, multiple fixed beams are shaped in sector, and multiple fixed beams are used to shape traffic channel with narrow beams and common channel with sector beams in one and the same intellectual antenna system, and problem of phases discrepancy is solved in appropriate channels due to differences in time and temperature oscillations without application of complicated correcting technology. Since fixed beams in some area correlate and interact with each other, or considerably weaken due to correlative summation of space vectors of every fixed beam in process of common channels transfer in CDMA system with multiple antennas, then appropriate ratio is established between power of pilot channel and traffic channel in coverage area, and signal-noise ratio is increased for signals received by mobile communication station. As a result of addition of optical transceivers system between system of the main frequency band and system of radio frequency transceivers (TRX), the main frequency band system services more sectors. Radio frequency unit is located in close proximity to antennas, and consumed power is reduced accordingly.

EFFECT: increased throughput capacity and efficiency of CDMA system with multiple antennas.

15 cl, 6 dwg

Description

Subject of invention

The present invention relates to the field of mobile communications and is a device and method for beam forming in a CDMA code division multiple access (CDMA) communication system. In particular, a device for forming beams using the technology of intelligent antennas in mobile communication mdcr (CDMA).

State of the art

In recent years, the CDMA mobile communication system (CDMA) 95 has received significant development and has been widely used, its most typical examples being the CDMA mobile communication systems (CDMA) 95 and CDMA (CDMA) 2000, which have received commercial use. Compared to mobile communication systems with a different mechanism (e.g., a TDMA time division multiple access system, FDMA frequency division multiple access system), a CDMA (CDMA) system has advantages in throughput and quality of service. However, since users of a CDMA system (CDMA) share a single single broadband channel, common channel interference (QSO) occurs for the respective users, limiting the throughput of a CDMA system. In addition, the rapidly growing number of mobile users and the ever-increasing demands on the quality of mobile communications require that the cells retain high voice quality and at the same time high throughput. With regard to reducing interference in the system and increasing throughput, this is usually done using a method using division of cells into sectors; however, too many sectors lead to an excessively high handover load in the system and generates a frequency distortion of the pilot signal; therefore, existing base station equipment typically employs a division into three or six sectors. In a busy urban area, it is sometimes necessary to further increase the throughput and system performance based on a sector base station. In this situation, other technologies are needed, for example, multi-carrier technology, smart antenna technology.

Smart Antenna Technology is a new mobile communications technology that includes a fixed multiple beam system and adaptive multiple beam system. A handover multiple beams system is a system in which a logical handover device is added to a fixed multiple beams system, which simplifies handoff between beam systems. In some documents, the fixed multiple-beam system and the handover multiple-beam system are collectively referred to as the fixed-beam system; this also applies to the present invention.

Intelligent antenna system controls the directivity of the rays using an antenna array, and is able to track changes in signals. Compared to omnidirectional antennas and sector antennas, the intelligent antenna system improves antenna gains due to narrow beams and, therefore, significantly improves signal reception quality.

Theoretically, an intelligent antenna system consisting of N antenna elements can provide a gain of 10 LogN dB in a channel with additive white Gaussian noise (AWGN), so with the same transmit power of the antenna array, the intelligent antenna system increases the coverage area of the base station; for example, if the path loss index is n = 4, 5 and an 8-element array is used, then the number of base stations required to cover this area will be reduced by 60% compared to the number of base stations when using a conventional antenna system. While maintaining the same coverage area, an intelligent antenna system improves the performance of the base station system, reduces the transmit power of the antenna element, and increases the efficiency of the base station.

An adaptive antenna system generates beams for transmitting and receiving user signals by adopting a specific adaptive rule. Although this system has great flexibility and good operational gain, it is difficult to implement and very difficult to upgrade to implement an intelligent antenna system based on the existing system.

Since the fixed-beam system of the smart antenna system further divides the sectors into narrow beams, the throughput of the smart antenna system is significantly higher compared to a conventional sector antenna system. For example, FIG. 1 shows a diagram of a conventional sector CDMA (CDMA) base station system. In FIG. 2, each sector shown in FIG. 1 is further divided into multiple beams sharing a single pilot signal, which reduces interference and the number of handovers and increases system throughput.

The fixed beamforming network uses either digital or analog beamforming technology.

An intelligent antenna has incomparable advantages in terms of eliminating interference, expanding the cell coverage area, reducing system costs and increasing system throughput.

The fixed-beam intelligent antenna system is suitable for use in existing CDMA (CDMA) systems, such as CDMA (CDMA) 95, CDMA (CDMA) 2000 and Broadband CDMA (WCDMA) systems, and the adaptive beam antenna system is compatible with in new CDMA (CDMA) systems, for example, in a multiple access system with synchronous code-time division multiplexing (TDMA (TD-SCDMA)). An adaptive beam intelligent antenna system requires a more sophisticated algorithm and correction method than a fixed beam intelligent antenna system.

When using the fixed-beam system in a CDMA (CDMA) system, not only multiple fixed narrow beams are generated for transferring user service information, but also sector beams covering the entire sector, which are used to transmit general user information, for example, pilot channel information, personal call channel and channel synchronization.

Currently, many feasible schemes have been proposed in this area of research.

One scheme is for transmitting general information when all fixed beams transmit traffic channels. However, the pilot channel of each of the rays, the vector sum of which is equal to the strength of the pilot channel at any point in space, is correlated. When adding the vectors of each beam to form a pilot channel, the overlap between the rays leads to incorrect summation in a certain region and to the appearance of the so-called “dead zone”, where, when a mobile station enters it, a significant deterioration in the quality of the speech signal and even disconnection of calls occurs.

In another design, in addition to radio frequency channels and antennas for generating fixed narrow beams, another radio frequency channel or group thereof and antennas are added to generate rays spanning the entire sector for transmitting general information (such as pilot channel information, paging channel, and synchronization channel). However, this method requires additional radio frequency elements and high power transmitting antennas, which leads to a rise in the cost of the system. In addition, since in this scheme the pilot and traffic channels pass through different radio frequency lines, a complex correction method is required to solve the problem of time and phase shifts in the pilot and traffic channels due to time differences and temperature fluctuations. US Pat. No. 6,094,165 discloses such a fixed beam generation scheme spanning a sector using an additional antenna array.

There is another scheme with a certain frequency shift between each of the fixed beams, which reduces the possibility of incorrect summation of the rays when forming the pilot channels. This scheme essentially refers to US patent No. US2002 / 0072393, in which the proposed frequency shift is 30-120 Hz, that is, if each sector has 3 beams, as is usual, the carrier offset in this part will reach ± 30 ~ 120 Hz IS-97 (“Minimum Criteria for Testing Base Station Performance in CDMA (CDMA) 95 and CDMA (CDMA) 2000” systems) requires that the base station transmit frequency (TX) tolerance be <± 0.05 ppm (parts per million, parts per million); therefore, if the frequency of the base station is 800 MHz, then the frequency offset of this part will be close to the tolerance for the transmission frequency of the base station or significantly exceed this tolerance, and therefore the offset of the receiving frequency will reduce the demodulation function of the mobile communication station.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a device and method for generating beams in a CDMA system using smart antenna technology to form multiple fixed beams in a CDMA system sector, with multiple fixed beams being used in an intelligent antenna system for simultaneously generating narrow traffic channels beams and common channels with sector beams (such as a pilot channel, a paging channel, and a synchronization channel), and the problem of phase disagreement of each channel but because of the time and temperature variations decide without complicated correctional technology that increases throughput and performance of the CDMA system (CDMA) with multiple antennas. Here, a CDMA (CDMA) system includes, but is not limited to, code division multiple access systems such as CDMA (CDMA) 95, CDMA (CDMA) 2000, WCDMA (CDMA), and multi-carrier CDMA (CDMA) (MC-CDMA) )) and MDSKR (TD-SCDMA), all of which apply the principle of spreading the spectrum.

The present invention is implemented as follows:

a device for forming beams in a CDMA system:

the specified device in the forward direction of signal transmission contains at least a baseband system, an optical interface module, a system of radio frequency transceivers, an analog network for the formation of fixed beams, a power amplifier, a transmitting radio frequency end filter and an antenna system;

the specified device in the direction opposite to the direction of signal transmission, contains an antenna system, a receiving radio frequency end filter, a low noise amplifier, an analog network for the formation of fixed beams, a system of radio frequency transceivers, an optical interface module and a system of a band of modulating frequencies;

the specified optical interface module containing a fiber light guide, an optical interface board located next to the system of the frequency band, and an optical interface board located next to the system of radio frequency transceivers, allows you to place the baseband system in the equipment room so that the baseband system serves more the number of sectors, and the RF block is next to the antennas, which reduces power loss;

the specified board optical interface is designed for the mutual conversion of electronic signals and input optical signals;

said baseband system consists of at least one baseband chip or / and one baseband logic device;

in a device consisting of an analog network for the formation of fixed beams, when transmitting signals in the forward direction, in order to avoid interaction between multiple beams forming a common channel, first, in the system of the modulating frequency band, different beams are given a different time delay so that even when carrying the same information they did not correlate with each other; further, after the signals pass through the fiber, each of the individual rays passes through a system of radio frequency transceivers corresponding to it, then the rays pass through an analog network of forming fixed rays, they are amplified, filtered and transmitted by the antenna and, finally, formed into rays of different spatial directions;

the specified device, including an analog network for the formation of fixed beams, is configured to control an analog network for the formation of fixed beams, a power amplifier, transmitting and receiving radio frequency end filters, a low noise amplifier, feeder and antenna system, as well as radio frequency cables between them;

the specified analog network for the formation of fixed beams is made in the form of a Butler matrix, or Blass matrix, or an electromagnetic Luneberg or Rotman lens;

said device comprises a baseband system, an optical interface module, a system of radio frequency transceivers, an analog fixed beam formation network formed by a Butler matrix, radio frequency cables between transceivers and an analog fixed beam formation network, radio frequency lines including a power amplifier, transmitting and receiving radio frequency end filters low-noise amplifier and feeder, as well as the antenna system;

said optical interface module, a system of radio frequency transceivers, an analog fixed beam generation network, an antenna system and radio frequency lines are arranged to be mounted on a mast or on a support rack so that the radio frequency cables between them are as short and easily adjustable as possible, which reduces output losses power amplifier power and increases coverage area;

the output signals of each sector in the specified system of the band of modulating frequencies pass, respectively, the system of transceivers, and then the analog network of the formation of fixed beams, after which they are respectively transmitted to the fixed beams;

rays formed by said common channels are equivalent to rays obtained by summing fixed rays;

a device for forming beams in a CDMA system in which:

said device comprising, in the forward direction of signal transmission, a baseband system, a digital fixed-beam forming network, an optical interface module, a system of radio frequency transceivers, a power amplifier, a radio frequency end filter and an antenna system;

the specified device in the opposite direction contains at least an antenna system, a receiving radio frequency end filter, a low noise amplifier, a system of radio frequency transceivers, a digital network for the formation of fixed beams and a band system of modulating frequencies;

the specified optical interface module, including a fiber optical fiber and an optical interface board located next to the baseband system, and an optical interface board located next to the radio frequency transceiver system, allows you to place the baseband system in the hardware room so that the baseband system serves more the number of sectors, and the RF block is next to the antenna, which reduces power loss;

the specified board optical interface is designed for the mutual conversion of electrical signals and input optical signals;

said baseband system consists of at least one baseband chip or / and one baseband logic device;

in a device consisting of a digital network for the formation of fixed beams, when transmitting signals in the forward direction, in order to avoid interaction between multiple beams forming common channels, at first in the system of the modulating frequency band different beams are given different time delays, so that even when carrying the same information they did not correlate with each other; then various beams pass through a digital network for the formation of fixed beams to acquire different spatial directions, then, passing through a fiber, various beams pass through their respective transceiver systems, after which they are amplified, filtered and transmitted by antennas and, finally, formed into beams of different spatial directionality;

the specified device, consisting of a digital network for the formation of fixed beams, is configured to control a system of radio frequency transceivers, a power amplifier, a transmitting and receiving radio frequency end filters, a low noise amplifier, a feeder and an antenna system, as well as radio frequency cables between them;

said device comprises a baseband system, a digital fixed beamforming network, an optical interface module, a system of radio frequency transceivers, radio frequency line elements such as a power amplifier, a transmit and receive radio frequency end filter, a low noise amplifier, a feeder, and the like, radio frequency cables between transceivers and radio frequency lines and an antenna system;

said device is capable of regulating a system of radio frequency transceivers, elements of a radio frequency line, including a power amplifier, a transmitting and receiving radio frequency end filters, a low noise amplifier, a feeder, etc., radio frequency cables between transceivers and radio frequency lines, an antenna system and radio frequency cables.

The output signals of the said baseband system are respectively transmitted to the fixed beams after passing through the digital network for the formation of fixed beams, the beams generated by these common channels being equivalent to the beams obtained by summing the fixed beams;

A beam forming method in a CDMA system, comprising at least the following steps:

Step 1. In the baseband, the baseband signals of each fixed beam are sent to the baseband sectors of the baseband;

Step 2. They give the baseband signals transmitted by the fixed beams to the corresponding sectors of the corresponding baseband baseband microcircuits a different time delay.

At the indicated step 1:

baseband signals of each fixed beam can be routed to different sectors of baseband chips;

the baseband signals of each fixed beam can also be routed to one sector of different baseband chips.

Also in step 1 above:

when transmitting user traffic on a channel, the transmission is performed only within the fixed beam where the user is located, i.e. fixed-beam baseband signals for this user are routed to one specific corresponding baseband sector;

if the user is among several beams, one or more narrow beams are selected depending on the power of several user beams received for transmitting user service data, i.e. the user baseband signals are sent to one or more of the respective sectors of the baseband chip.

Also in step 1 above:

when transmitting common user channels, information of common channels is transmitted in each fixed beam, i.e. common channel information is sent to each sector of the microcircuit band of the baseband.

Indicated step 2:

can be implemented in microchips of the band of modulating frequencies;

can also be implemented by digital logic components located after the baseband chips, i.e. implemented in the band of modulating frequencies.

In step 2 above:

the value of the time delay must meet the criterion of the absence of correlation with each other of the output signals of each sector in the chips of the band of modulating frequencies when transmitting information of common channels;

when transmitting general information to the beams at the ends of the antennas, various time delays are given, so the beams do not correlate with each other when forming beams of common channels, therefore there is no problem of correlation and interaction of fixed beams with each other in a certain area when forming beams spanning entire sectors.

The device and method according to the claimed invention solves the problem that fixed beams in a certain area correlate and interact with each other or are very weakened due to the correlation summation of the spatial vectors of each fixed beam when transmitting common channels in a CDMA system with multiple antennas and determine the power of the pilot channel and the traffic channel in an appropriate proportion in the coverage area. Compared with the prior art, the claimed invention simplified the equipment, algorithm and design of control circuits and improved the signal-to-noise ratio of signals received by the mobile station. Adding an optical interface module between the baseband system and radio frequency transceivers (TRX) has the goal, using a fiber optic cable, to place the transceivers (TRX) and other radio frequency systems closer to the antennas, which allows you to place the baseband system in the equipment room (indoors), and also allows the baseband system to serve a larger number of sectors, and placing RF elements near the antennas reduces power consumption.

Brief Description of the Drawings

Figure 1 presents a diagram of the network architecture of a CDMA base station system (CDMA) with a conventional sector antenna (sectors with an angle of 120 ° are shown as an example);

Figure 2 presents a network architecture diagram of a CDMA base station system (CDMA) with an intelligent sector antenna (as an example, sectors of an intelligent antenna with an angle of 120 ° are shown, where each sector has 3 fixed beams and 1 sector beam);

3 is a diagram of an embodiment of a baseband system;

On figa presents a diagram of an intelligent sector antenna system using the architecture of the analog network of the formation of fixed beams (such as the Butler matrix);

FIG. 4B is a diagram of an intelligent sector antenna system with an implementation of a digital fixed beamforming digital network architecture;

Figure 5 presents a block diagram of an algorithm for selecting signals of a modulating frequency band of fixed beams for receiving and transmitting user signals in a sector smart antenna system.

Detailed Description of Embodiments

The device and method according to the present invention is made according to the following schemes:

The smart antenna beam forming apparatus used in CDMA (CDMA) systems is as follows:

The fixed beam forming network may use digital or analog beam forming technology. Therefore, in accordance with various beam forming technologies, the fixed beam forming device of the smart antennas used in CDMA systems is divided into an analog beam forming device and a digital beam forming device.

In this case, the analog device for generating fixed beams of smart antennas used in the CDMA system contains, in the direction of direct transmission of signals, at least a baseband system, an optical interface module, a system of radio frequency transceivers (TRX), an analog network for generating fixed beams (such as a Butler matrix), a power amplifier that transmits a radio frequency end filter and an antenna system. And in the opposite direction of direct signal transmission, it contains at least an antenna system, a radio frequency end filter, a low-noise amplifier, an analog fixed-beam network (like a Butler matrix), a radio frequency transceiver system (TRX), an optical interface module and a modulating band system frequencies.

When an analog device for the formation of fixed beams transmits signals in the forward direction, then, in order to avoid the interaction of multiple beams that form common channels, first in the system of the modulating frequency band different beams are given different time delays in such a way that even when different beams carry the same the same information, they do not correlate with each other, then each individual beam passes through its corresponding system of optical transceivers of the optical interface module, after First, the rays pass through an analog network of formation of fixed rays, they are amplified, filtered, transmitted by antennas and, finally, formed into rays of different spatial directions.

An analog device for the formation of fixed beams is configured to regulate only an analog network for the formation of fixed beams (such as a Butler matrix), a power amplifier, a radio frequency terminal filter, feeder and antenna system, as well as radio frequency cables between them. The radio frequency cables of the radio frequency transceiver system and the cables between the radio frequency transceivers and the analog fixed-beam network do not need to be adjusted. Therefore, the regulation of the analog device for the formation of fixed beams is relatively simple.

In an analog network for the formation of fixed beams of an analog device for the formation of fixed beams, either a Butler matrix or other types of matrices are used. For example, Blass matrix or Luneberg or Rotman electromagnetic lens can also be used as equipment for beam forming.

The digital device for generating fixed beams of smart antennas used in the CDMA system contains in the direction of direct transmission of signals at least a baseband system, a digital network for generating fixed beams, an optical interface module, a system of radio frequency transceivers (TRX), transmitting radio frequency end filter and antenna system. And in the direction opposite to the signal transmission direction, it contains at least an antenna system, a radio frequency end filter, a low noise amplifier, a radio frequency transceiver (TRX) system, an optical interface module, a digital fixed-beam signal generation network, and a baseband system.

When a digital fixed-beam forming device transmits signals in the forward direction, then, in order to avoid the interaction of multiple beams forming common channels, different time delays are first applied to the beams in the baseband system so that even when the different beams carry the same information, they do not correlate with each other, then each individual beam passes through its respective system of optical transceivers of the optical interface module, after which the rays pass are handled by the digital network forming fixed beams, they amplify, filter, transmitting antennas, and finally formed into beams of different spatial orientation.

The digital device for the formation of fixed beams is made with the possibility of regulating the system of radio frequency transceivers, a power amplifier, a transmitting radio frequency end filter, feeder and antenna system, as well as radio frequency cables between them.

The smart antenna beam forming method used in CDMA systems of the present invention is as follows:

Step 1. In the baseband, the baseband signals of each fixed beam are sent to the baseband sectors of the baseband.

At this step, the signals of the modulating frequency band of each fixed beam can be directed not only to different sectors of the microcircuits of the modulating frequency band, but also to the same sector of different microcircuits of the modulating frequency band, and in both cases they perform the same function. For example, if fixed beams are directed to the same sector of different microcircuits of the baseband frequency band, then when using three microcircuits, three beams of the first sector are sent respectively to the same sector α of three microcircuits, three beams of the second sector to the same sector β, and the three rays of the third sector into the same sector γ. At this step, when transmitting in a user’s traffic channel, transmission is carried out only within a certain fixed beam where the user is located, that is, the signals of the modulating frequency band of fixed beams for this user are sent to one specific corresponding sector of the microcircuit of the modulating frequency band.

If the user is among several beams, it is possible to select one or several narrow beams depending on the power of several user beam signals received for transmitting user service data, that is, the baseband signals of the user are sent to one or more corresponding sectors of the baseband chip;

At this step, when transmitting common user channels, common channel information is transmitted in each fixed beam, i.e. common channel information is sent to each sector of the microcircuit band of the baseband.

Step 2. The signals of the modulating frequency band of each fixed beam directed to the corresponding sectors of the respective microcircuits of the modulating frequency band are given a different time delay. This step is also performed in the baseband chips and, of course, it can also be performed by digital logic elements located after the baseband chips, that is, it is performed in the baseband.

The value of the time delay corresponds to the condition that there is no correlation with each other of the output signals of each chip of the modulating frequency band when transmitting information of common channels.

The goal of this step is to make the signals of the modulating frequency band of all fixed beams that form a common channel of the entire sector not correlated with each other, which solves the problem of the correlation and interaction of the beams with each other in a certain area or their significant attenuation due to the correlation summation of the spatial vectors of the corresponding rays.

The multiple antenna beam forming method used in a CDMA system can also be implemented using an analog fixed beam generating device with multiple antennas of a CDMA system and using a digital fixed beam generating device with multiple antennas of a CDMA system.

The following is a detailed description of embodiments of the technical schemes of the claimed invention with reference to the accompanying drawings:

Figure 1 schematically shows the structure of the sector system of cellular mobile communications. Due to the limitation of the frequency resource of mobile communication, a mobile communication system with a cellular structure is a well-established and widely used form of the network structure of a system of terrestrial base stations of mobile communication. Depending on the differences in traffic in the coverage area, a cellular base station may use an omnidirectional base station, or it may also use a sector base station. 1, base stations 100 and 101 are a base station system with a structure of three sectors, with a coverage area of each sector of 120 °. In a real system, the size and number of sectors can be appropriately changed depending on the amount of traffic.

Figure 2 schematically shows the structure of the sector system of cellular mobile communication with an intelligent antenna system. Compared to a cellular mobile communication system with a conventional sector-based antenna system, this system can increase throughput and reduce the number of base stations. In the drawings, pos. 200 refers to a three-sector base station with an intelligent antenna system; pos. 201 refers to a single-sector base station adjacent to station 200 using an intelligent antenna system. Each sector of the base station includes several pre-generated fixed beams.

Take, for example, sector 210 of base station 200 with fixed beams 222, 224 and 226, where a certain degree of overlap between two adjacent fixed beams is required to prevent the occurrence of a “dead zone” and thereby ensure that the rays cover the entire sector. In a real system design, the number of fixed beams in each sector is set freely according to the volume of traffic and the size of the sector. When the user 230 enters sector 210, the base station, after comparing the reception signals from the fixed beams 222, 224 and 226, selects one beam with the best signal quality or several beams with relatively good signal quality as the receiving beam; in the latter case, the signals of the selected beams are combined. The time delay of the baseband system is adjusted to give different time delays to the signals of the main range, so the beams will not correlate with each other even when they give the same signals, while the time delays of the fixed beams 222, 224 and 226 at the ends of the antennas are also different; thus avoiding the problem that the ray signals in a certain region are significantly attenuated due to the correlation summation of the rays, and form a sector beam 220, covering the entire sector, as shown in FIG. 2. This sector beam is intended mainly, but not limited to, for transmitting general user information, for example, pilot information, and, of course, it can also transmit traffic information and receive user information. When a user moves along the boundaries between sectors 210, 211 and 212, base stations 200 and 201 support a handover function between sectors, the principle of operation being similar to that of a conventional sector antenna system.

For the claimed invention, FIG. 3 is a diagram of an embodiment of a baseband system, FIG. 4A is a diagram of a sector smart antenna system using an analog fixed-beam network (for example, a Butler array), FIG. 4B is a diagram of a sector smart antenna system using digital architecture of the formation of fixed beams.

It is well known that in a CDMA (CDMA) system, the pseudo-random code used to expand the spectrum of the pilot signal has sufficiently self-defined and correlated characteristics, i.e. the self-determining value of the pseudo-random code itself is very high. However, when a pseudo-random code is correlated with another pseudo-random code, which is equal to it or has one chip more, its relative value is very small, almost equal to zero. To use this feature in CDMA (CDMA) systems, the rays at the ends of the antennas are given different time delays in transmitting common information so that they do not correlate with each other when forming the rays of common channels (when the correlation value is close to zero, the rays will naturally not correlate with each other); thus eliminating the problem of correlation and interaction of fixed beams with each other when creating beams to cover the entire sector. For example, we give beam 224 the normal offset of the pilot signal in sector 210 and denote the normal offset as t ₂₂₄ , beam 226 is 1-5 chips ahead of beam 224, and beam 222 is 1-5 chips behind beam 224. When choosing a specific time interval Δt from 1-5 chips, the temporal shift of the transmission of the beam 226 is t ₂₂₆ = t ₂₂₄ -Δt, and the temporal shift of the transmission of the beam 222 is t ₂₂₂ = t ₂₂₄ + Δt.

At the same time, the duration of each chip is slightly different from each other in different CDMA (CDMA) systems. In CDMA (CDMA) 95 and CDMA (CDMA) 2000 systems, the duration of one chip is 1 / 1.2288 MHz = 0.814 μs; in the system MDSKR (TD-SCDMA), it is equal to 1 / 1.28 MHz = 0.78 μs; in the system ШПМДКР (WCDMA) - 1 / 3.84 MHz = 0.26 μs. The duration of five chips is equal to the duration of one chip times five; for example, in CDMA (CDMA) 95 and CDMA (CDMA) 2000 systems, the duration of 5 chips is 4.07 μs.

4A, 4B, the respective baseband signals of the beams 226, 224, and 222 are converted to 301, 302, and 303, respectively, by using an analog fixed-beam network or digital fixed-beam technology. Since the time delays of the radio frequency line from the output signals 301, 302, 303 of the system 300 of the baseband to the antenna system 460 (order of nanoseconds) can be neglected compared with the time delays at the chip level (order of microseconds), the time offsets corresponding to the output signals 301, 302, 303 of the baseband system 300, is defined as t ₃₀₁ = t ₂₂₆ = t ₂₂₄ -Δt = t ₃₀₂ -Δt, t ₃₀₂ = t ₂₂₄ = t ₃₀₂ , t ₃₀₃ = t ₂₂₂ = t ₂₂₄ + Δt = t ₃₀₂ + Δt, i.e. with respect to the output signal 302 of the baseband system 300, the output signal 301 of the baseband system 300 is ahead of the output signal 302 of the baseband system 300 by Δt, and the output signal 303 of the baseband system 300 is Δt behind the output signal 302 of the baseband system 300 modulating frequencies, with Δt being one particular time delay selected from 1-5 chips, as mentioned earlier. The relative time offset of the output of the output signals 301, 302, 303 of the baseband system 300 can be implemented in a baseband chip and, of course, can also be implemented in a digital logic element after the baseband chip. This is described in detail below with reference to FIG. 3.

FIG. 3 is a schematic diagram of a baseband system of a baseband system, showing only a baseband system 300 of a sector 210 of a base station 200. Assume that a baseband system of a sector 210 is comprised of baseband chips 310, 320, and 330 and a logic unit 305 baseband bands. This is only one specific embodiment of the invention, and in fact, the number of baseband chips can vary from one to many. The output signals 331, 332, 333 of the baseband chip 330 correspond to the output signals of the three sectors α, β, γ of the baseband chip 330, respectively, the output signals 321, 322, 323 of the baseband chip 320 correspond to the output signals of the three sectors α, β, γ baseband chips 320, respectively, and output signals 311, 312, 313 of baseband chips 310 correspond to the output signals of three sectors α, β, γ of baseband chips 310, respectively. Since the baseband chips 330, 320 and 310 are serially connected to each other, the output signals 331, 332, 333 of the α, β, γ sectors are integrated baseband chips 330 are sequentially connected to the inputs of the sectors α, β, γ of the baseband chip 320, respectively ; the output signals 321, 322, 323 of the sectors α, β, γ of the baseband chip 320 are connected in series to the inputs of the sectors α, β, γ of the baseband chip 310, respectively; that is, sectors α, β, γ of the chips 330, 320, 310 of the baseband are respectively connected in series with each other.

In step 1 of the claimed invention, as shown in Figs. 4A, 4B, using an analog fixed-beam forming network or digital fixed-beam forming technology, the output signals of the baseband system 300 corresponding to the three beams 226, 224 and 222 are respectively converted to 301, 302 and 303, which corresponds to the output signals 311, 312 and 313 of the sectors α, β, γ of the baseband chip 310, respectively, so that the baseband signals 301, 302, 303 of the fixed-frequency beams 226, 224 and 222 are sent to the corresponding sectors α, β, γ of the chip of the modulating frequency band.

At this step, when transmitting in a user’s traffic channel, transmission is carried out only within a certain fixed beam where the user is located, that is, the signals of the modulating frequency band of fixed beams for this user are sent to one specific corresponding sector of the microcircuit of the modulating frequency band. For example, the user traffic channel is transmitted in a fixed beam 226, it corresponds to the output signal 301 of the baseband, and, accordingly, it is sent to the sector α of the baseband chip. Of course, if the user is among several beams, then one or several narrow beams are selected depending on the power of several user beam signals received for transmitting user service data, i.e., the baseband signals of the user are sent to one or more corresponding sectors of the baseband chip .

At this step, when transmitting a common user channel, the information of this channel is transmitted in each fixed beam, that is, the information of the common channel is sent to each sector of the microchip of the baseband frequency band.

Step 2 of the claimed invention, in which the signals of the modulating frequency band directed from the fixed beams to the corresponding sectors of the microcircuit of the modulating frequency band are given various time delays, can be performed both in the microchip of the modulating frequency band and by digital logic elements located after the microchip of the modulating band frequencies.

In a situation where a time delay is performed in the baseband chips, one can dispense with the baseband logic unit 305. As described above, the time delay of the output signals 301, 302 and 303 of the baseband system 300 is t ₃₀₁ = t ₃₀₂ -Δt, t ₃₀₃ = t ₃₀₂ + Δt, and Δt is one particular time delay selected from 1-5 chips as described above, and its temporal accuracy can be from 1 to 2 chips, for example, one chip or one and a half chips. Without the logic 305 of the baseband, this time the time offsets of the output signals 311, 312, 313 of the baseband chip 310 coincide with the time delays of the output signals 301, 302, 303 of the baseband system 300, respectively. Suppose the technological time delay of the baseband chips is τ, then the time offsets of the output signals 321, 322 and 323 of the baseband chip 32 are t ₃₂₁ = t ₃₀₂ -Δt-τ, t ₃₂₂ = t ₃₀₂ -τ and t ₃₂₃ = t ₃₀₂ + Δt-τ, respectively, and the time delays of the output signals 331, 332, 333 of the chip 330 of the baseband frequency are respectively t ₃₃₁ = t ₃₀₂ -Δt-2τ, t ₃₃₂ = t ₃₀₂ -2τ and t ₃₃₃ = t ₃₀₂ + Δt- 2τ.

The method for implementing the time delay by the baseband logic unit 305 is similar to the method for performing time control in microcircuits. But when the time delay is implemented by the baseband logic device 305, the time shift of the output signals of the baseband chips can only be delayed, not advanced, moreover, the technological time delay in the baseband logic device 305 itself must also be taken into account. The implementation of the time delay by the baseband logic 305 is also within the scope of the patent protection of the present invention.

The value of the time delay corresponds to the condition that there is no correlation of the signals with each other at the output of each sector of the microchips of the band of modulating frequencies when transmitting information of common channels.

The purpose of this step is to ensure that there is no correlation between the signals of the modulating frequency band of the fixed beams that form a common channel of the entire sector, and, therefore, the problem of correlation and interaction of beams with each other in a certain region or their significant attenuation due to the correlation summation of spatial vectors rays when forming a common channel.

It should be separately noted that the “sector” attribute used in step 1 when it comes to the transmission of fixed beams to the corresponding “sectors” of the baseband chips, and the “sector” attribute used in step 2 when it comes to the formation of a common channel all "sectors" have different meanings. The first feature relates to the corresponding sectors in the baseband chips, with the region covered by narrow beams, for example, 222, 224, 226, shown in FIG. 2; the latter refers to an area 220 covered by a common channel formed from all fixed beams.

The method for generating common beams of multiple antennas according to the claimed invention used in a CDMA system can also be adapted to an analog device for generating fixed beams with multiple antennas of a CDMA system and to a digital device for forming fixed beams with multiple antennas of a CDMA system )

In FIG. 4A shows an analog fixed beamforming device with an intelligent antenna used in a CDMA system and comprising a baseband system 300, an optical interface module consisting of an optical interface board 400 located adjacent to the baseband system and an optical interface board 432, adjacent to the TRX transceiver and optical fiber 410 between the optical interface cards 400 and 432, a radio frequency transceiver (TRX) system comprising transceivers ki 434, 436 and 438, and an analog network 440 for the formation of fixed beams (such as a Butler matrix), elements of the radio frequency line 450, including a power amplifier, transmitting and receiving radio frequency end filters, low-noise amplifier, feeder, etc., as well as an antenna system 460. Since the analogue fixed-beam-forming network should only regulate the fixed-beam-forming analogue network 440, the radio frequency line 450 between the fixed-beam-forming analogous network 440 and the antenna system 460, the antenna system 460 and the radio frequency cables between them, then the fixed-beam analog network 440, antenna system 460 and radio frequency line 450 are placed on the mast or support post 430 so that the radio frequency cables between them are as short as possible. Thus simplify regulation and reduce the loss of output power generated by the power amplifier; which increases the coverage area. Radio frequency cables of the radio frequency transceiver system 434, 436 and 438, as well as radio frequency cables between the specified system of radio frequency transceivers and the analog network 440 do not require the formation of fixed control beams.

The outputs 301, 302, and 303 of the baseband system 300 in the analog fixed beamforming apparatus of FIG. 4A pass through an optical interface module comprising an optical interface board 400 located adjacent to a baseband system, a fiber optic fiber 410 and an optical interface board 432 located adjacent to a TRX radio frequency transceiver, then TRX0, TRX1, TRX2 of a radio frequency transceiver system (TRX ) 434, 436 and 438 and the analog network 440 for the formation of fixed beams and, finally, they are transmitted respectively to beams 226, 224 and 222. The rays formed by the common channel are equivalent to the beam 220 obtained by summing iem fixed beams 226, 224 and 222.

FIG. 4B shows a digital fixed beam forming apparatus with an intelligent antenna used in a CDMA system including a baseband system 300, a digital fixed beam forming network 470, an optical interface module consisting of an optical interface board 400 located next to the baseband system, the optical interface board 432 located next to the TRX transceiver and the optical fiber 410 between the optical interface boards 400 and 432, a radio system frequency transceivers (TRX) 434, 436 and 438, radio frequency lines 450, including a power amplifier, receiving and transmitting radio frequency end filters, low noise amplifier, feeder and the like, radio frequency cables between transceivers 434, 436 and 438 and elements of the radio frequency line 450 and antenna system 460. In a digital fixed-beam device, radio frequency transceiver cables (TRX) 434, 436 and 438, radio frequency lines 450, including a power amplifier, transmit and receive radio frequency end filters, low noise power spruce, feeder, etc., RF cables between the transceivers 434, 436 and 438 and the RF lines 450 and antenna system 460, and radio frequency cables therebetween.

The outputs 301, 302, and 303 of the baseband system 300 in the digital fixed beamforming device, as shown in FIG. 4B, are transmitted to beams 226, 224, 222, respectively, after passing through the digital fixed beamforming network 470. The rays formed by the common channel are equivalent to the beam 220 obtained by summing the fixed beams 226, 224 and 222.

The fixed-beam intelligent antenna system is capable of further dividing sectors with narrow beams, which can significantly increase the system throughput compared to a conventional sector-based antenna system. Separating a single pilot signal between multiple beams helps reduce interference and the number of handovers, which increases system throughput. As shown in FIG. 2, the single beam sector in FIG. 1 is divided into sectors by three beams separating one pilot signal; thus, the system capacity is 200% ~ 300% of the single-beam source sector.

Figure 5 shows a block diagram of the selection of narrow-band fixed beams for receiving and transmitting user signals in a sector smart antenna system, which is a working block diagram of the selection of beams according to a method for comparing the power of received user signals. First, user signals are received by all beams, then the power of the received user signals in each beam is compared, one or more beams are selected with the most powerful user signals, and then signals are received / transmitted. As shown in FIG. 2, when the user 230 enters sector 210, the base station, after comparing the reception signals of the fixed beams 222, 224 and 226, selects one beam with the best signal quality or several beams with a relatively high signal quality as the reception rays; then the signals of each beam are combined.

Although the claimed invention considers a situation in which 3 antennas generate 3 beams in each sector as a preferred embodiment, any system created according to the principle of the claimed invention using several antennas and beams for each sector falls within the scope of patent protection of the claimed invention.

The foregoing is a description of preferred embodiments of the claimed invention; the specialist should understand that various modifications and changes fall under the principle of the present invention and in the field of patent protection of the attached claims.

Claims (15)

1. A device for forming beams in a multiple access communication system with code division multiplexing CDMA (CDMA), comprising:
in the forward direction of signal transmission, at least a modulating frequency band system, an optical interface module, a system of radio frequency transceivers, an analog fixed-beam generation network, a power amplifier transmitting a radio frequency terminal filter and an antenna system;
in the direction opposite to the signal transmission, at least the antenna system, the receiving radio frequency end filter, low-noise amplifier, an analog fixed-beam generation network, a system of radio frequency transceivers, an optical interface module and a baseband system;
moreover, the optical interface module containing the optical interface board next to the baseband system, the optical interface board next to the radio frequency transceiver system and the optical fiber between the optical interface boards allows you to place the baseband system in the hardware room, so that the baseband system serves a larger number sectors, while the specified board optical interface, located next to the specified system of radio frequency receivers transmitters are specified system radio frequency transceiver, the analog network forming fixed beams, receiving and transmitting radio frequency filters terminal, a power amplifier and low noise amplifier are located near the antenna system, which reduces the power loss;
the specified board optical interface is designed for the mutual conversion of electronic signals and input optical signals;
when transmitting signals in the forward direction to prevent interaction between multiple beams forming a common channel, first the output signals of the baseband system corresponding to the fixed beams are given a different time delay so that they do not correlate with each other, even when different beams carry the same information; further, after the signals have passed through the fiber, various signals pass through various systems of radio frequency transceivers; after passing through their respective systems of radio frequency transceivers, the rays pass through an analog network for the formation of fixed beams, where they are amplified, filtered and transmitted using antennas, forming rays of different spatial directions. 2. The device according to claim 1, characterized in that said modulating frequency band system consists of
at least one baseband chip and one time delay logic device for output signals. 3. The device according to any one of claims 1 or 2, characterized in that the said device is configured to regulate an analog network for the formation of fixed beams, a power amplifier, transmitting and receiving radio frequency end filters, a low noise amplifier, feeder and antenna system, as well as radio frequency cables between them. 4. The device according to any one of claims 1 or 2, characterized in that said analog network for the formation of fixed beams is made in the form of a Butler matrix or Blass matrix or an electromagnetic Luneberg or Rotman lens. 5. The device according to any one of claims 1 or 2, characterized in that said optical interface module, a system of radio frequency transceivers, an analog network for the formation of fixed beams, an antenna system and radio frequency lines between them are arranged to be placed on a mast or support rack so that the radio frequency the cables between them were as short as possible and easily adjustable, which reduces the loss of output power of the power amplifier and increases the coverage area;
the output signals of the specified system of the band of modulating frequencies respectively pass through a system of radio frequency transceivers, then pass through an analog network for the formation of fixed beams, after which they are respectively transmitted to fixed beams;
the rays formed in the specified common channel are equivalent to the rays obtained by summing the fixed rays. 6. A device for forming beams in a communication system mdcr (CDMA), containing:
in the forward direction of signal transmission, at least a baseband system, a digital fixed-beam signal generation network, an optical interface module, a radio frequency transceiver system, a power amplifier, a radio frequency end filter and an antenna system;
in the direction opposite to the signal transmission, at least the antenna system, the receiving radio frequency end filter, low-noise amplifier, the system of radio frequency transceivers, optical interface module, digital network for generating fixed-beam signals and a modulating frequency band system;
moreover, the optical interface module containing the optical fiber, the optical interface board located next to the baseband system, and the optical interface board located next to the radio frequency transceiver system, allows you to place the baseband system in the hardware room, so that the baseband system serves more the number of sectors, while the specified board optical interface, located next to the specified system of radio frequency transceivers The indicated radio-frequency transceiver system, radio-frequency receiving and transmitting end filters, power amplifier and low-noise amplifier are located next to the antenna system, which reduces power losses;
the specified board optical interface is designed for the mutual conversion of electronic signals and input optical signals;
when transmitting signals in the forward direction to prevent interaction between multiple beams forming a common channel, first, in the system of the modulating frequency band, the output signals corresponding to different beams are given a different time delay so that the beams do not correlate with each other, even when different rays carry the same information; further, the signals of various beams pass through a digital network of the formation of signals of fixed beams, receiving a different spatial orientation; after passing through the fiber, the signals of various beams pass through various systems of radio frequency transceivers, after which they are amplified, filtered and transmitted using antennas, forming beams of different spatial directions. 7. The device according to claim 6, characterized in that said modulating frequency band system consists of
at least one baseband chip and one time delay logic device for output signals. 8. The device according to any one of claims 6 or 7, characterized in that said device is configured to control a system of radio frequency transceivers, a power amplifier, a transmitter and a receiver of radio frequency end filters, a low noise amplifier, a feeder and an antenna system, as well as radio frequency cables between them . 9. A device according to any one of claims 6 or 7, characterized in that said device is configured to control a system of radio frequency transceivers, elements of a radio frequency line, including a power amplifier, a transmitting and receiving radio frequency end filters, a low noise amplifier and a feeder, radio frequency cables between transceivers and radio frequency lines, an antenna system, and radio frequency cables between the above systems;
the output signals of the said baseband system are respectively transmitted to fixed beams after passing through a digital network for generating fixed beams, and the beams generated in the common channel are equivalent to the beams obtained by summing the fixed beams. 10. A method of forming beams in a communication system mdcr (CDMA), containing at least the following steps:
the baseband system produces multiple signals, each channel corresponding to a separate beam, with different beams having different time delays. 11. The method according to claim 10, characterized in that when transmitting in a user’s traffic channel, the transmission is carried out only within a certain beam where the user
if the user is among several beams, one or more narrow beams are selected in accordance with the power of several user beam signals received for transmitting user service data. 12. The method according to claim 10, characterized in that when transmitting information of each user in a common channel, information of this channel is transmitted in each fixed beam. 13. The method according to claim 10, characterized in that the procedure for imparting a time delay is performed in baseband chips; or
perform using digital logic elements located after the microcircuit band of the modulating frequency, that is, perform in the main frequency band. 14. The method according to claim 10, characterized in that the amount of time delay is such that each beam transmitting general information is uncorrelated, which reduces the unwanted effects of signal cancellation. 15. The method according to claim 10, characterized in that when transmitting the general information, the rays of the common channel to the rays at the ends of the antennas give different time delays so that they do not correlate with each other when forming the rays of the common channels, in order to avoid the interaction of fixed beams with each other in some region, when each fixed ray is an integral part of the rays covering the entire sector.

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