HK1130971B - A method and system for processing communication signal - Google Patents

Description

Method and system for processing communication signals

Technical Field

The present invention relates to signal processing for communication systems, and more particularly to a method and system for a distributed transceiver for high frequency applications.

Background

In 2001, the Federal Communications Commission (FCC) specified a large continuous 7GHz bandwidth for communication in the 57GHz to 64GHz spectral range. This band can be used arbitrarily without applying for a use license. That is, anyone can access the spectrum as long as certain basic requirements, technical limitations, such as maximum transmit power and specific coexistence mechanisms, are met. The communication occurring in this band is said to be 60GHz communication.

As to the accessibility of this designated portion of spectrum, 60GHz communications and other forms of use that do not require the application of a spectrum license, such as wireless local area networks or bluetooth within the 2.4GHz ISM band, are similar. However, in addition to accessibility, 60GHz communications differ greatly in many ways. For example, 60GHz signals can provide significantly different communication channels and propagation characteristics, at least by the fact that 60GHz radiated signals can be partially absorbed by atmospheric oxygen, resulting in higher attenuation of long range signals. On the other hand, large data rate transmission can be achieved because a large bandwidth of 7GHz is available. Various 60GHz communication applications include wireless personal area networks, wireless high definition television signals, such as from a set-top box to a display device, or point-to-point connections.

The limitations and disadvantages of conventional and existing approaches will become apparent to one of skill in the art, through comparison of some aspects of the present system with those of the present system, after reading the following description and drawings.

Disclosure of Invention

A system and/or method for a distributed transceiver for high frequency applications, substantially as shown in and/or described in connection with at least one of the figures, as set forth more completely in the claims.

According to one aspect of the present invention, there is provided a method of processing a communication signal, comprising:

frequency converting the first signal through a plurality of conversion stages, thereby generating a second signal from the first signal; wherein:

each conversion stage of the plurality of conversion stages frequency converts a respective input signal with a local oscillation frequency or a portion of the local oscillation frequency; and

the first signal is a respective input signal of an initial stage of the plurality of conversion stages, an output signal of a previous stage of the plurality of conversion stages is a respective input signal of a subsequent stage, and the second signal is an output signal of a final stage of the plurality of conversion stages.

In the method of the present invention, the plurality of conversion stages are communicatively coupled in a cascade.

In the method of the present invention, the first signal is a radio frequency signal or an intermediate frequency signal, and the second signal is a baseband signal.

In the method of the present invention, the first signal is a radio frequency signal or a baseband signal, and the second signal is an intermediate frequency signal.

In the method of the present invention, the first signal is a baseband signal or an intermediate frequency signal, and the second signal is a radio frequency signal.

In the method of the present invention, the local oscillation frequency is associated with a local oscillation signal, and a part of the local oscillation frequency is associated with a part of the local oscillation signal.

In the method of the present invention, the method further comprises generating the partial local oscillation signal from the local oscillation signal by using one or more frequency dividers.

In the method of the present invention, the method further comprises mixing the local oscillation signal and/or one or more mixed signals to generate the partial local oscillation signal.

In the method of the present invention, the method further comprises dividing the local oscillator signal by one or more frequency dividers to generate the one or more mixing signals.

In the method of the present invention, the local oscillation signal is a sinusoidal signal having a frequency equal to the local oscillation frequency.

According to one aspect of the present invention, there is provided a system for processing a communication signal, the system comprising:

one or more circuits that frequency convert a first signal through a plurality of conversion stages to generate a second signal from the first signal, wherein:

each conversion stage of the plurality of conversion stages frequency converts a respective input signal with a local oscillation frequency or a portion of the local oscillation frequency; and

the first signal is a respective input signal of an initial stage of the plurality of conversion stages, an output signal of a previous stage of the plurality of conversion stages is a respective input signal of a subsequent stage, and the second signal is an output signal of a final stage of the plurality of conversion stages.

In the system of the present invention, the plurality of conversion stages are communicatively coupled in a cascade.

In the system of the present invention, the first signal is a radio frequency signal or an intermediate frequency signal, and the second signal is a baseband signal.

In the system of the present invention, the first signal is a radio frequency signal or a baseband signal, and the second signal is an intermediate frequency signal.

In the system of the present invention, the first signal is a baseband signal or an intermediate frequency signal, and the second signal is a radio frequency signal.

In the system of the present invention, the local oscillation frequency is associated with a local oscillation signal, and a part of the local oscillation frequency is associated with a part of the local oscillation signal.

In the system of the present invention, the one or more circuits generate the portion of the local oscillator signal from the local oscillator signal by using one or more frequency dividers.

In the system of the present invention, the one or more circuits mix the local oscillation signal and/or one or more mixed signals to generate the partial local oscillation signal.

In the system of the present invention, the one or more circuits divide the local oscillator signal by one or more frequency dividers to generate the one or more mixed signals.

In the system of the present invention, the local oscillation signal is a sinusoidal signal having a frequency equal to the local oscillation frequency.

Further features and advantages of the invention, as well as the architecture and operation of various embodiments of the invention, are described in detail below with reference to the accompanying drawings.

Drawings

Fig. 1 is a schematic diagram of a wireless communication system according to an embodiment of the present invention;

FIG. 2 is a block diagram illustrating RF demodulation of a high frequency receiver according to an embodiment of the present invention;

fig. 3 is a schematic diagram of the structure of rf modulation and demodulation of the high frequency transceiver according to an embodiment of the present invention;

FIG. 4 is a flow chart illustrating the determination of the down-conversion factor of the demodulator according to one embodiment of the present invention;

fig. 5 is a schematic diagram of a demodulator with local oscillator mixing according to one embodiment of the present invention.

Detailed Description

The invention will be further explained with reference to the following figures and examples:

certain embodiments of the invention relate to a method and system for a distributed transceiver for high frequency applications. Exemplary aspects of the invention include generating a second signal from a first signal by frequency transforming the first signal through a plurality of conversion stages. Each of which may frequency translate the respective input signal by a local oscillation frequency or a fraction of said local oscillation frequency. The first signal may be a corresponding input signal of an initial stage of the plurality of conversion stages, an output signal of a previous stage of the plurality of conversion stages is a corresponding input signal of a subsequent stage, and the second signal is an output signal of a final stage of the plurality of conversion stages.

The plurality of conversion stages may be communicatively coupled in a cascaded manner. The first signal may be a radio frequency signal or an intermediate frequency signal and the second signal may be a baseband signal. The first signal may be a radio frequency signal or a baseband signal and the second signal may be an intermediate frequency signal. The first signal may be a baseband signal or an intermediate frequency signal and the second signal may be a radio frequency signal. The local oscillation frequency may be associated with a local oscillation signal, and a portion of the local oscillation frequency may be associated with a portion of the local oscillation signal. The portion of the local oscillator signal may be generated from the local oscillator signal using one or more frequency dividers. Mixing the local oscillator signal and/or the one or more mixing signals may generate a portion of the local oscillator signal. The one or more mixing signals may be generated by dividing the local oscillation by one or more frequency dividers. The local oscillation may be a sinusoidal signal having a frequency equal to the local oscillation frequency.

Fig. 1 is a diagram of a wireless communication system in accordance with one embodiment of the present invention. As shown in fig. 1, there is shown an access point 112b, a computer 110a, a headset 114a, a router 130, the internet 132, and a web server 134. The computer or host device 110a may include a wireless transceiver 111a, a short-range radio 111b, a main processor 111c, a main memory 111 d. Also shown is a wireless connection between the wireless transceiver 111a and the access point 112b, and a short-range wireless connection between the short-range radio 111b and the headset 114 a.

Typically, computing and communication devices have software and hardware to communicate using a variety of wireless communication standards. For example, the wireless transceiver 111a may comply with a mobile communication standard. It is an example that the wireless transceiver 111a and the short-range radio 111b may operate simultaneously. For example, to obtain streaming media content from the server 134, a user of a computer or host device 110a is eager to access the internet 132. Thus, the user may establish a wireless connection between the computer 110a and the access point 112 b. Once this connection is established, the computer or master device 110a may receive the streaming media information on the server 134 through the router 130, the access point 112b, and the wireless connection.

Further, a user of the computer 110a may wish to hear the audio portion of the streaming media content over the headphones 114 a. Thus, a user of the computer 110a may establish a short-range wireless connection with the headset 114 a. Once this short-range wireless connection is established and the appropriate configuration on the computer is activated, the audio portion of the streaming media can be played on the headphones 114 a. In this example, when such an advanced communication system is integrated or housed within the host device 110a, rf generation may support multiple communication standards and/or advanced broadband systems, such as ultra-wideband radios, by supporting fast switching. Other short-range communication applications may be wireless high definition television (W-HDTV), such as from set-top boxes to video displays. The high data rates required for high definition television may be achieved by large bandwidth communication techniques, such as UWB and/or 60GHz communication.

Fig. 2 is a schematic diagram of an RF demodulator of a high frequency receiver in accordance with an embodiment of the present invention. As shown in fig. 2, there is shown a demodulator 200 including an amplifier 202, a plurality of down-conversion stages, such as down-conversion stages 204, 206 and 208 as shown. The down conversion stage 204 may include a multiplier 210a and a filter 212 a. Down conversion stage 206May include a multiplier 210b, a filter 212b, and a divider 214 b. The down-conversion stage 208 may comprise a multiplier 210c, a filter 212c and a divider 214 c. Also shown as carrier frequency f₀Received signal r as a function of time t₀(f₀，t)＝r₀. For purposes of illustration, the indices of frequency and time may be discarded. Similarly, r is also shown₁、r₂、r_k、r_a、r_b. The figure also shows the local oscillation signals c respectively_LO(f_LO，t)＝c_LOAnd a plurality of partial local oscillator signals、、Respectively having frequency termsAndthese partial local oscillator signals represent a Local Oscillator (LO) signal c by frequency division_LOAnd various signals generated.

The amplifier 202 may comprise suitable logic, circuitry, and/or code that may enable amplification of a high frequency RF signal at an input. The down-conversion stages 204,205, 206 may be very similar in that they comprise suitable logic, circuitry and/or code that may down-convert an input signal modulated onto an RF carrier signal into an output signal that is similar to the input signal but modulated onto a lower frequency carrier signal. The multipliers 210a/b/c may comprise suitable logic, circuitry and/or code that may be operable to multiply two RF input signals to generate an RF output signal that is proportional to the product of the input signals. The filters 212a/b/c may comprise suitable logic, circuitry and/or code that may be enabled to attenuate portions of the input signal spectrum. The frequency divider 214b/c may comprise suitable logic, circuitry, and/or code that may enable generation of an output signal that is similar to its input signal but divided in frequency. For example, the frequency divider may be implemented by using a direct digital frequency synthesizer or an integer (miller) frequency divider.

As shown in fig. 2, a demodulator 200 is shown which is part of a high frequency rf receiver. r is₀(f₀，t)＝s(t)cos(2πf₀t+φ(t))＝s(t)cos(w₀t + φ (t)) is the received high frequency signal, where f₀Is the carrier frequency, 2 pi f₀＝w₀Is the corresponding angular frequency. The signal s (t) and the phase signal s (t) are modulated onto the carrier cos (w), respectively₀t) information-carrying baseband signals and information-carrying phase signals. In this example, r₀(f₀And t) is the in-phase bandpass signal component. A similar structure as shown in demodulator 200 may also be used to demodulate the quadrature bandpass signal components. In some cases, the received signal r₀At a high frequency carrier frequency, e.g. f₀60 GZ. In these cases, a phase-locked loop (PLL) is used to generate a local oscillator signal c that is sufficiently high in frequency_LOIt is difficult to implement demodulation to baseband or intermediate frequency. In addition, it is generally undesirable for a high frequency LO signal to be transmitted in a system because its transmission in a conductor can cause problems with the transmission line due to the high frequency content of the LO signal. Therefore, in order to approach the received high frequency signal r₀(f₀T), a high frequency signal needs to be generated to demodulate the RF signal. In these cases, it is necessary to generate a very low frequency local oscillator signal c_LOE.g. f_LO20GHz, well below f₀The carrier frequency of the received signal is 60 GHz. According to various embodiments of the invention, a plurality of conversion stages, such as down-conversion stages 204205, 206, may be used to down-convert the received signal r₀To baseband and/or to an intermediate frequency.

The following is one example: received signal r₀Amplified by a factor z in amplifier 202 to produce a signal to the input of multiplier 210a, r'₀(f₀，t)＝z·r₀(f₀，t)＝z·s(t)cos(w₀+ φ (t)). The multiplier 210a outputs a signal r 'according to the following relationship'₀And a local oscillation signal c_LO＝cos(w_LOt) are multiplied to generate r_a：

Thus, as can be seen from the above equation, the signal r_aMay comprise a sum and a difference at a frequency, which is defined by the carrier frequency w₀And a local oscillation frequency w_LOIs determined. In this example, it is desirable to demodulate the received signal, according to embodiments of the present invention, so that only the low frequency component needs to be retained and remodulated to a frequency w₀-w_LOOn the carrier wave of (a). This is achieved by filter 212 a. Filter 212a rejects the higher frequency portion to generate r₁Given by the following relation:

the signal r generated at a further down-conversion stage, such as down-conversion stage 206₁May be further converted down. This can be achieved in a similar way as above, i.e. by down-converting r with the divided local oscillator signal₁. As shown in particular in fig. 2, the down-converted output signal r from the down-conversion stage 204₁Multiplied by the divided local oscillator signal output by the output of divider 214b, i.e.Divisor N applied in frequency divider 214b₁And may be arbitrary. In many cases, it is desirable to select N₁Are rational or integer numbers. The signal r generated at the output of the multiplier 210b_bThis can be derived from the following relation:

(1)

similar to generate r₁R generated at the output of the down-conversion stage 206₂Can be measured by pairing r_bAppropriate filtering is applied to generate, removing the higher frequency components in filter 212b, obtaining:

further down-modulation may be achieved using a further down-conversion stage, similar to down-conversion stage 206. As shown in fig. 2, it needs to be implemented using cascaded K down-conversion stages. In this case, the output signal r after the K down-conversion stages_KThis can be derived from the following relation:

in these examples, the filters in the down conversion stages, such as filters 212a/b/c, may filter high frequencies, i.e., attenuate high frequency components in their inputs. In this case, the number of the first and second terminals,。

some down conversion stages in some examples, it is desirable to choose to preserve the high frequency component of the multiplier output rather than the low frequency component in order to obtain the desired output at the filter. For example, according to an embodiment of the present invention, equation (1) r_bThe higher frequency components within may be retained after appropriate filtering in filter 212 b. In this example, r is according to equation (1)₂This can be obtained by the following relation:

in the general case, higher or lower frequency components may be selected for each down-conversion stage. This may result in a change in sign of the frequency term corresponding to a particular down conversion stage, as shown in equation (3). Thus, for K down conversion stages, r is output_KCan be described by equation (2) where the coefficient N_kEither positive or negative, as the case may be.

In one embodiment of the invention, the divisor N_kCan be chosen to be equal, i.e.. In these cases, equation (2) can be given by the following relation:

by amplifying with a factor of 2 at each down conversion stage, z-2 can be achieved^K. By selecting z as 2^KIt can be seen that when |1/N<1, the behavior of equation (4) is stable and can be converged for any number of switching stages, so the limit value of equation (4) can be derived by the following relation:

(5)

where equation (5) can converge more quickly for larger N. For example, if N is 4 and K tends to infinity, the frequency terms in equation (5) may converge to w₀t-1.3·w_LOt. However, as can be seen from the first line of equation (5), when K is 3, the frequency term is already w₀t-1.3125·w_LOt. Thus, the frequency correction term is about the desired frequency correction term

The number of down-conversion stages may be arbitrary, in accordance with various embodiments of the present invention. Furthermore, in some cases, a first down conversion stage, such as down conversion stage 204, may include a frequency divider, as may down conversion stage 206 and/or down conversion stage 208. The number of down conversion stages K may be represented by w₀And w_LOIs determined from the difference of (a) and the desired intermediate frequency. In some examples, it is also possible that the divisor is programmed by software. In addition, the structure shown in fig. 2 may be applied by a modulator. In this way, the sum term, rather than the difference term, may be retained to obtain an output signal at a higher frequency than the input signal. For example, in equation (1), the higher frequency components may be retained by the filter 212b within the down-conversion stage 206, so that the down-conversion stage 206 may effectively become an up-conversion stage, as shown in equation (3).

Fig. 3 is a schematic diagram of an RF modulator and demodulator of a high frequency transceiver in accordance with one embodiment of the present invention. As shown in fig. 3, a modulator/demodulator system 300 is shown that includes a modulator 320 and a demodulator 330. Demodulator 320 is very similar to demodulator 200 shown in fig. 2. The components of demodulator 320 are similar to the corresponding components of demodulator 200. Specifically, components 302, 304, 306, 308, 310a/b/c, and 314b/c are similar to components 202, 204, 206, 208, 210a/b/c, 212a/b/c, and 214b/c, respectively.

The modulator 330 includes an amplifier 302a and a plurality of up-conversion stages, here shown as up-conversion stages 304a, 306a and 308 a. The modulator 330, which may comprise suitable logic, circuitry, and/or code, may modulate the input signal r_T0Becomes a radio frequency r_TK. The subscript "T" represents the transmitted signal associated with modulator 330. The up-conversion stages 304a, 306a and 308a include filters 312d/e/f and multipliers 310d/e/f, respectively. Here also shown as frequency f_T0Transmitted signal r as a function of time t_T0(f_T0，t)＝r_T0. The frequency and time indices may be reduced for illustrative purposes. Similarly, r is shown here_T1、r_T(K-1)、r_TKWhich are the output signals of the up-conversion stage 1, (K-1) and K, respectively.

The functionality of modulator 330 is considered similar to the inverse functionality of demodulator 320. In particular, in demodulator 320, input signal r is input₀Which may be a signal modulated onto a radio frequency carrier or an intermediate frequency carrier, for frequency conversion to a lower frequency. The input signal to the modulator 330 may be a baseband signal or an intermediate frequency signal for frequency conversion to a higher frequency, such as an intermediate frequency or a radio frequency. However, frequency up-conversion may be implemented in a similar way as down-conversion. The main difference is in the filter where the higher frequency components are preserved, as depicted in diagram 2 and equation (3). For example, in the up-conversion stage 308a, the signal r is output_T1Can be given by the following relation:

(6)

wherein w_T0＝2πf_T0May be the input signal r_T0＝x(t)cos(w_T0t + phi (t)), where x (t) is the information-bearing baseband signal and phi (t \) is the information-bearing phase signal, which are analogous to s (t) and phi (t), respectively, of the received signal. For an up-conversion stage, such as up-conversion stage 308a, filter 312f may hold r in equation (6)_TaHigher frequency component of so r_T1This can be derived from the following relation:

similar to fig. 2, filter 312f may be a random filter, e.g., to preserve lower and/or higher frequency components contained in its input signal, and may not be limited to the expression of equation (7).

Modulator 330 may share a frequency divider, such as frequency divider 314b/c, with demodulator 320, in accordance with one embodiment of the present invention. Modulator 330 may be configured to up-convert the same frequency steps as down-convert. It is to be noted in particular that if the filters at the down-conversion stages retain lower frequency components, by retaining higher frequency components at the corresponding up-conversion stages, the up-converted signal can be up-converted by the same amount of frequency as if the down-converted signal were down-converted by the corresponding down-conversion stages. For example, it isAs shown in fig. 2, the received signal r₀Angular frequency w of₀May be down-converted to a signal r at a down-conversion stage 304_T1W of₁＝w₀-w_LO. Similarly, the angular frequency is w_T(K-1)Signal r of_T(K-1)May be converted to an angular frequency w by a corresponding up-conversion stage 304a_TK＝w_T(K-1)+w_LO. Thus, by selecting appropriate filters in the demodulator 320 and the modulator 330, the frequency translation across the entire modulator is substantially the same as the frequency across the entire demodulator, with opposite directions. In an exemplary embodiment of the invention, the received signal r is₀Can be selected from r₀Down-converting 40GHz to r_KSending a signal r_T0Can convert 40GHz to r upwards_TK。

In some cases, the high frequency transceiver of fig. 3 may operate in a time division duplex (TTD) mode, so that the signal r to be transmitted is generated in the modulator 330_TKThe demodulator 320 receives the signal r₀. In one embodiment of the present invention, in any event, the high frequency transceiver 300 is either receiving signals or transmitting signals, but not both. In these examples, frequency dividers, such as frequency dividers 314b and/or 314c, may be programmable, which may use different divisors depending on whether the transceiver is transmitting or receiving. Thus, the signal r is transmitted because different divisors can be applied by different operating modes_TK(f_KT) of a transmission carrier frequency f_KAnd in some cases may be different from the received signal r₀Of the receiving frequency f₀. In this mode of operation, as shown in fig. 3, sharing a programmable divider may allow transceiver system 300 to operate in a combined TDD/FDD mode, where different frequencies may be used in modulator 330 and demodulator 320 depending on the mode of operation as a function of time.

Fig. 4 is a flow chart of determining a down-conversion factor of a demodulator in one embodiment of the invention. From the description of fig. 2 and 3, it will be appreciated by those skilled in the art that there are numerous ways to select to determine the plurality of frequency conversion stages and the appropriate frequency conversion factor. As shown in fig. 4, there is illustrated a method that may be used to determine the number of frequency conversion stages and the associated conversion factors and/or divisors.

The determination of a down-conversion system such as a demodulator similar to that of fig. 2, in accordance with an exemplary embodiment of the present invention, is shown in fig. 4. First, at step 404, a reduction factor is determined. The reduction factor, e.g. x, may be derived from the carrier frequency w of the received signal₀And the desired demodulator output carrier frequency w_KIs determined by the difference of (a). This reduction factor can be expressed by the local oscillator frequency, which can be given by the following relation:

based on this reduction factor, in step 406, the number of transitions, i.e., numbers, may be given by the following relationship, according to the present exemplary method:

wherein the operationRepresenting the most recent large integer. In this example, for K conversion stages, K-1 conversion stages may be selected such thatAt step 408, the down-conversion factor N of the Kth down-conversion stage may be selected accordingly_KIs due to 0<N_K<1 and can be given by the following relation:

wherein the operationRepresenting the nearest small integer, the operation ≈ may be interpreted as a "very close rational number" depending on the accuracy required by the system.

In one embodiment of the invention, at w₀Is 60GHz, the target frequency w_KIs 1GHz, the local oscillation frequency w_LOIs 8GHz, x-7.375. Thus, K-8 conversion stages may be used. Therefore, the temperature of the molten metal is controlled,and is

Fig. 5 is a schematic diagram of a demodulator with local oscillator frequency mixing according to one embodiment of the present invention. As shown in fig. 5, the demodulation system 500 presented herein includes an amplifier 502, down-conversion stages 504, 506, and 508, an LO mixer 520, and a partial LO cascade 530. The down-conversion stages 504, 506 and 508 may include multipliers 510a/b/c and filters 512a/b/c, respectively. LO mixer 520 includes filter 512d/e and multiplier 510 d/e. The partial LO cascade 530 includes dividers 514 a/b/c. Here shown received signal r₀(f₀，t)＝r₀Is receiving a carrier waveFrequency f₀And time t. For purposes of illustration, the indices of frequency and time may be discarded. Similarly, r is shown here₁、r₂、r₃、r_a、r_b、r_c、r_m1、r_m2、r_m3And a local oscillation signal c_LO(f_LO，t)＝c_LOAnd a plurality of frequency termsAndthese representations are by means of a frequency-division Local Oscillation (LO) signal c_LOVarious signals generated thereby, e.g. c_LO(f_LO/N，t)、c_LO(f_LO/N²，t)、c_LO(f_LO/N³，t)。

In some examples, the type of frequency divider, e.g., 214b/c, is constrained due to the particular implementation. Such as, for example,in this regard, the divisor can only be selected from a positive integer. In other embodiments of the invention as shown in fig. 5, the frequency divider may be more restrictive and. Nonetheless, in some instances at the expense of applying LO mixer 520, even though N is fixed, in accordance with an embodiment of the present invention_KHigh accuracy can also be achieved. Such as whenAccording to equation (5), it can be seen that the frequency terms can be converged toWhere the phase term phi (t) is omitted for illustrative purposes. For different series K, the term correction term can be seen from the following tableHow to converge:

thus, as seen from the second column of the table above, by increasing the number of down-conversion stages, the correction term can be selected to be close to 2, as shown in the third column of the table above. For example, if K ═ 2, an error of 12.5% can be obtained with respect to K ∞. Therefore, in the correction termWhen selected as an integer greater than or equal to 2, any accuracy can be readily achieved. For example, in the system of fig. 2, the number of stages N is such that the correction factor 5 is 3+2_K1 is ═ 1; k ∈ 0, 1, 2 to obtain a factor of 3, followed by an arbitrary number of conversion stagesTo obtain an arbitrary approach of 5.

To be based on a fixed divisorAny frequency correction term is generated and both LO mixer 520 and partial LO cascade 530 may be utilized. The partial LO cascade 530 may comprise suitable logic, circuitry, and/or code that may be enabled to receive a local oscillator input signal c_LO(f_LOT) and divides this signal in cascaded frequency dividers e.g. 514a/b/c, and then generates part of the local oscillator signal e.g. c, respectively_LO(f_LO/N，t)、c_LO(f_LO/N²，t)、c_LO(f_LO/N³T). By properly mixing these partial local oscillator signals, a small frequency difference is obtained, which difference can be used in the down-conversion stage. This result, or frequency span, that is achievable depends on the number of dividers in the partial LO cascade 530. For example, exemplary fig. 5 includes 3 dividers 514a/b/c, which may be set to N-2. By appropriately multiplying or filtering the partial LO terms obtained from the partial LO cascade 530 of the LO mixer 520, any down-conversion factor can be achieved at the down-conversion stage for a sufficient frequency divider in the LO cascade 530.

The embodiment of FIG. 5 obtains an overall down-conversion factor of 4.125, r₃∝cos(w₀t+φ(t)-4.125w_LOt). Within mixer 520, a multiplier 510d is communicatively coupled to c_LOAnd the output of multiplier 510d may be given by the following relation:

similar to the filtering described in fig. 2, the filter 512d may retain low or high frequency components. In this particular case, the filter 512d may retain the high frequency component while generating the signal r at its output_m1Given by the following relation:

signal r_m1May be communicatively coupled to the multiplier 510a within the down-conversion stage 504. Similarly, the output of divider 514b may be coupled to the input of multiplier 510b, and, therefore,as observed from fig. 5, the output of divider 514b may be coupled directly to down-conversion stage 506 without prior mixing at LO mixer 520. Similarly, in this embodiment of the present invention, it may be observed that the output of divider 514a may not be coupled to LO mixer 520 or to a down-conversion stage. In contrast, of frequency divider 514aThe output may be used as an input to divider 514 b.

The output of the divider 514c may be communicatively coupled to a multiplier 510 e. A second input of multiplier 510e may be coupled to an output of filter 512 d. Thus, the output of multiplier 510e in the LO mixer may be represented by the following relationship:

by preserving the low frequency content of the output signal in filter 512e, the output signal of filter 512e can be derived from the following relation:

within the down-conversion stage 504, the signal r is output₁This can be derived from the following relation:

wherein filter 512a is selected to retain low frequency components and r₀＝s(t)cos(w₀t) · z is the amplification factor introduced by amplifier 502, similar to the description of fig. 2. Likewise, the output of the down conversion stage 506 may be given by the following relation:

where the low frequency components have been retained by filter 512 b. The output of the down conversion stage 508 may be given by the following relation:

thus, as described above, the output signal r that may be generated by the down-conversion stage₃The frequency transformation may be performed by a factor of 4.125. Any down-conversion (frequency conversion) factor can be obtained by suitably selecting the number of frequency dividers in the partial LO cascade and suitably combining the outputs of the frequency dividers in LO mixer 520. In various embodiments of the present invention, similar methods may also be used for the modulator by appropriate filtering at switching stages 504, 506 and 508, as described above and with reference to fig. 2.

According to one embodiment of the present invention, a method and system for a distributed transceiver for high frequency applications may include pairing a first signal r through a plurality of switching stages as shown in fig. 2, 3 and 5₀Frequency conversion is performed to generate a second signal r from the first signal_K. For each of the number of conversion stages,such as switching stages 204, 206 and 208, may switch the respective input signal by a local oscillator frequency or a fraction of the local oscillator frequency, as shown in fig. 2. The first signal may be a corresponding input signal of an initial stage of the plurality of conversion stages, the output signal of a previous stage may be a corresponding input signal of a subsequent stage, and the second signal may be an output signal of a final stage of the plurality of conversion stages.

As shown in fig. 5, the plurality of conversion stages may be communicatively coupled in a cascaded manner. The first signal may be a radio frequency signal or an intermediate frequency signal and the second signal may be a baseband signal. The first signal may be a radio frequency signal or a baseband signal and the second signal is an intermediate frequency signal. The first signal may be a baseband signal or an intermediate frequency signal and the second signal is a radio frequency signal, as described in connection with fig. 2. Local oscillation frequency, e.g. w_LOWith local oscillator signals, e.g. c_LOAssociating; a portion of the local oscillator frequency, e.g. w_LO/N, part of local oscillator signals, e.g. c_LOand/N association. Portions of the local oscillator signal may be derived from the local oscillator signal c using one or more frequency dividers such as 514a/b/c_LOAnd (4) generating. Mixing the local oscillation and/or one or more mixed signals may generate a partial local oscillation signal, as shown in fig. 2. Dividing the local oscillator signal by one or more frequency dividers may generate the one or more mixed signals. The local oscillator signal may be a sinusoidal signal having the same frequency as the local oscillator.

Another embodiment of the invention is to provide a machine readable storage, having stored thereon, a computer program comprising at least one code section for execution by a machine for causing the machine to perform the steps of the method for distributed transceiver for high frequency applications as described above.

Thus, the invention may be implemented in hardware, software, or a combination of hardware and software. The invention can be implemented by at least one computer system, a central control mode or computer systems with different elements connected with each other. Any kind of computer system or other apparatus adapted for carrying out the methods described herein is suited. A typical combination of hardware and software could be a general-purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the functions and acts described above.

A computer program product may also be embedded in the invention, which comprises all the features enabling the implementation of the methods described herein, and which when loaded in a computer is able to carry out these methods. The computer program in this document may be embodied in any form of language, code or notation. It is a set of instructions that can perform a specific function, giving the system information processing capabilities. It is either directly the above-described manner or one or both of the following: a) conversion to another language, code or notation; b) reconstituted with other forms of material.

While the invention has been described in terms of embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Accordingly, it is intended that the invention not be limited to the embodiments disclosed herein. But that the invention will include all embodiments falling within the scope of the appended claims.

Claims (8)

1. A method of processing a communication signal, the method comprising:

frequency converting the first signal through a plurality of conversion stages, thereby generating a second signal from the first signal; wherein:

each conversion stage of the plurality of conversion stages frequency converts a respective input signal with a local oscillation frequency or a portion of the local oscillation frequency; the local oscillation frequency is associated with a local oscillation signal, and a part of the local oscillation frequency is associated with a part of the local oscillation signal; and

the first signal is a respective input signal of an initial stage of the plurality of conversion stages, an output signal of a preceding stage of the plurality of conversion stages is a respective input signal of a subsequent stage, and the second signal is an output signal of a final stage of the plurality of conversion stages;

the method comprises generating a partial local oscillator signal by dividing a local oscillator signal using a partial local oscillator cascade; the method comprises obtaining a frequency difference by mixing the portions of the local oscillator signal; the method comprises implementing a down-conversion factor at a down-conversion stage by multiplying or filtering a portion of a local oscillation term obtained from a partial local oscillation cascade of a local oscillation mixer.

2. The method of claim 1, wherein the plurality of conversion stages are communicatively coupled in a cascade.

3. The method of claim 1, wherein the first signal is a radio frequency signal or an intermediate frequency signal and the second signal is a baseband signal.

4. The method of claim 1, wherein the first signal is a radio frequency signal and the second signal is an intermediate frequency signal.

5. A system for processing a communication signal, the system comprising:

one or more circuits that frequency convert a first signal through a plurality of conversion stages to generate a second signal from the first signal, wherein:

each conversion stage of the plurality of conversion stages frequency converts a respective input signal with a local oscillation frequency or a portion of the local oscillation frequency; the local oscillation frequency is associated with a local oscillation signal, and a part of the local oscillation frequency is associated with a part of the local oscillation signal; and

the first signal is a respective input signal of an initial stage of the plurality of conversion stages, an output signal of a preceding stage of the plurality of conversion stages is a respective input signal of a subsequent stage, and the second signal is an output signal of a final stage of the plurality of conversion stages;

the one or more circuits generate a partial local oscillator signal by dividing a local oscillator signal using a partial local oscillator cascade; the one or more circuits derive a frequency difference by mixing the portions of the local oscillator signals; the one or more circuits implement a down-conversion factor at a down-conversion stage by multiplying or filtering a portion of a local oscillation term obtained from a partial local oscillation cascade of a local oscillation mixer.

6. The system of claim 5, wherein the plurality of conversion stages are communicatively coupled in a cascade.

7. The system of claim 5, wherein the first signal is a radio frequency signal or an intermediate frequency signal and the second signal is a baseband signal.

8. The system of claim 5, wherein the first signal is a radio frequency signal and the second signal is an intermediate frequency signal.