CN112039613B - Processing method and device for asymmetric PCMA (pulse code division multiple Access) mixed signal - Google Patents

Abstract

The application discloses a processing method and a device for an asymmetric PCMA mixed signal, wherein the method comprises the following steps: performing parameter estimation on a to-be-processed PCMA mixed signal to obtain a channel parameter, wherein the to-be-processed PCMA mixed signal comprises a useful signal and an interference signal, and the channel parameter comprises a frequency offset parameter, a phase parameter and an amplitude parameter of the interference signal; carrying out digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and check bit data; reconstructing according to the channel parameter, the information bit data and the check bit data to generate the interference signal, and subtracting the to-be-processed PCMA mixed signal from the interference signal to obtain the useful signal. The method and the device solve the technical problem that in the prior art, the effect of eliminating the interference signals in the PCMA mixed signals is poor.

Description

A kind of processing method and device of asymmetric PCMA mixed signal

technical field

The present application relates to the technical field of signal processing, and in particular, to a method and device for processing asymmetric PCMA mixed signals.

Background technique

With the increasing demand of users, the development of centralized high-throughput satellite systems is limited. In order to solve the problem of large antenna diameter of a single gateway station in a centralized high-throughput satellite system, high requirements for radio frequency systems, a large number of equipment, and a large area of Due to the very high cost of system construction, maintenance and operation, the industry has begun to try to adopt a distributed feeder system.

In order to improve the utilization of frequency resources in distributed feeder systems, paired carrier multiple access (PCMA) technology emerges as the times require. According to the energy of the two signal components in the PCMA mixed signal, it can be divided into symmetrical and asymmetrical PCMA mixed signals. From the perspective of usage scenarios, asymmetric PCMA mixed signals are more widely used in satellite communication systems. In the asymmetric mode, the signal sent by the ground station terminal is forwarded by the satellite transponder and then sent to the master station. After receiving the ground station terminal signal, the master station mixes the ground station terminal signal and the master station self-interference signal to obtain asymmetric PCMA. mixed signal. Since the power of the terminal signal (useful signal) of the ground station received by the main station is much smaller than the power of the self-interference signal of the main station, it is necessary to eliminate the self-interference signal in the asymmetric PCMA mixed signal.

At present, the common process of eliminating the interference signal in the asymmetric PCMA mixed signal is as follows: the asymmetric PCMA mixed signal is subjected to digital frequency conversion filtering to obtain the processed PCMA mixed signal, and then, the processed PCMA mixed signal is stored. The processed PCMA mixed signal is subjected to parameter estimation to obtain channel parameters; the stored local sequence is subjected to LDPC decoding to obtain the decoded local sequence, and then the decoded local sequence is modulated to obtain the modulated local sequence, and then according to the channel The parameters adjust and reconstruct the frequency offset, phase and amplitude of the modulated local sequence to obtain the interference signal. Finally, the asymmetric PCMA mixed signal and the reconstructed interference signal are differentiated to obtain the useful signal. Specifically, FIG. 1 shows a schematic flow chart of a traditional asymmetric PCMA mixed signal processing; FIG. 2 shows an effect diagram of a traditional asymmetric PCMA mixed signal processing. Therefore, in the prior art, the interference signal is reconstructed based on the local sequence. This method based on the local sequence is not only difficult to obtain a high signal-to-noise ratio, but also has high implementation complexity, thereby reducing the interference to the PCMA mixed signal. The effect of signal cancellation.

SUMMARY OF THE INVENTION

The technical problem solved by the present application is: in view of the problem that the interference signal elimination effect in the PCMA mixed signal is poor in the prior art, the present application provides a processing method and device for an asymmetric PCMA mixed signal. The embodiments of the present application provide In the scheme, the interference signal is reconstructed according to the information bit data and check bit data obtained by decoding the PCMA mixed signal and the channel parameters estimated by the PCMA mixed signal, so the interference signal is closer to the actual interference signal in the PCMA mixed signal, and then Improves the effect of eliminating interference signals in PCMA mixed signals.

In a first aspect, an embodiment of the present application provides a method for processing an asymmetric PCMA mixed signal, the method comprising:

Perform parameter estimation on the PCMA mixed signal to be processed to obtain channel parameters, wherein the PCMA mixed signal to be processed includes a useful signal and an interference signal, and the channel parameters include a frequency offset parameter, a phase parameter, and an amplitude parameter of the interference signal;

digital signal processing is performed on the PCMA mixed signal to be processed to obtain information bit data and check bit data;

The interference signal is generated by reconstruction according to the channel parameter, the information bit data and the check bit data, and the useful signal is obtained by subtracting the PCMA mixed signal to be processed and the interference signal.

In the solution provided by the embodiment of the present application, the PCMA mixed signal to be processed is subjected to parameter estimation to obtain channel parameters, and the PCMA mixed signal to be processed is subjected to digital signal processing to obtain information bit data and parity bit data. The parameters, the information bit data and the check bit data are reconstructed to generate the interference signal, and the useful signal is obtained by subtracting the PCMA mixed signal to be processed and the interference signal. Therefore, in the solution provided by the embodiment of the present application, the interference signal is reconstructed according to the information bit data and check bit data obtained by decoding the PCMA mixed signal and the channel parameters estimated by the PCMA mixed signal, so the interference signal is closer to PCMA The actual interference signal in the mixed signal, thereby improving the effect of eliminating the interference signal in the PCMA mixed signal.

Optionally, parameter estimation is performed on the PCMA mixed signal to be processed to obtain channel parameters, including:

Perform frequency offset estimation on the PCMA mixed signal to be processed to obtain the frequency offset parameter;

performing phase estimation on the PCMA mixed signal to be processed to obtain the phase parameter;

The amplitude parameter is obtained by performing amplitude estimation on the PCMA mixed signal to be processed.

Optionally, performing frequency offset estimation on the PCMA mixed signal to be processed to obtain the frequency offset parameter, including:

Set the frequency search times and the search frequency range, divide the search frequency range into a plurality of first sub-intervals, and calculate the metric parameter corresponding to each of the first sub-intervals, and obtain the metrics from the plurality of first sub-intervals. Search for the maximum value of the metric parameter in the parameters, and the frequency corresponding to the maximum value;

Reducing the search frequency range to obtain a narrowed search frequency range, determining a new search frequency range according to the frequency and the narrowed search frequency range, and judging whether the current frequency search times is less than the frequency search times;

If it is less than, dividing the new search frequency range into a plurality of second sub-intervals, and calculating the metric parameters corresponding to each of the second sub-intervals, and obtaining the metric parameters from the plurality of second sub-intervals Search out the maximum value of the metric parameter and the frequency corresponding to the maximum value, until the current frequency search times is not less than the frequency search times, take the maximum value of the metric parameter and its corresponding frequency as the last search. the frequency offset parameter.

Optionally, performing phase estimation on the PCMA mixed signal to be processed to obtain the phase parameter, including:

Perform frequency offset processing on the PCMA mixed signal to be processed according to the frequency offset parameter to obtain a PCMA mixed signal after frequency offset removal;

According to the preset operation method, the fourth power operation is performed on the PCMA mixed signal after the frequency offset is removed, and the operation result is simplified to obtain the simplified operation result;

Calculate the phase value of the interference signal according to the simplified operation result.

Optionally, performing amplitude estimation on the PCMA mixed signal to be processed to obtain the amplitude parameter, including:

Determine the mean value of the simplified operation result and the quadratic mean value of the preset local sequence;

The amplitude value of the interference signal is calculated according to the mean value of the simplified operation result and the fourth power mean value of the preset local sequence.

Optionally, performing digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and check bit data, including:

Perform down-conversion processing on the PCMA mixed signal to be processed to obtain a zero-IF signal, and perform rate conversion processing on the zero-IF signal to obtain a low-rate PCMA mixed signal;

Filtering the low-rate PCMA mixed signal to obtain a filtered signal, and converting the filtered signal into a digital baseband signal;

Decoding the digital baseband signal to obtain the information bit data and the parity bit data.

Optionally, performing reconstruction to generate the interference signal according to the channel parameter, the information bit data and the check bit data, including:

generating an interference sequence according to the information bit data and the check bit data;

Demodulating the interference sequence to obtain a demodulated interference sequence, and adjusting the frequency offset, phase and amplitude of the demodulated interference sequence according to the channel parameters to obtain the interference signal.

In the solution provided by the embodiment of the present application, the signal bit data and check bit data obtained by decoding are used to reconstruct the interference sequence directly in the process of reconstructing the interference signal. Therefore, coding is not required in the process of generating the interference sequence, which reduces the need for coding. The difficulty of reconstructing the interference signal makes it easier to eliminate the interference signal in the PCMA mixed signal.

In a second aspect, an embodiment of the present application provides an apparatus for processing an asymmetric PCMA mixed signal, the apparatus comprising:

A parameter estimation unit, configured to perform parameter estimation on the PCMA mixed signal to be processed to obtain channel parameters, wherein the PCMA mixed signal to be processed includes a useful signal and an interference signal, and the channel parameter includes a frequency offset parameter of the interference signal, Phase parameters and amplitude parameters;

a digital signal processing unit, configured to perform digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and check bit data;

a reconstruction unit, configured to reconstruct and generate the interference signal according to the channel parameter, the information bit data and the check bit data, and obtain the interference signal by subtracting the PCMA mixed signal to be processed and the interference signal the useful signal.

Optionally, the parameter estimation unit is specifically used for:

Perform frequency offset estimation on the PCMA mixed signal to be processed to obtain the frequency offset parameter;

performing phase estimation on the PCMA mixed signal to be processed to obtain the phase parameter;

The amplitude parameter is obtained by performing amplitude estimation on the PCMA mixed signal to be processed.

Optionally, the parameter estimation unit is specifically used for:

Set the frequency search times and the search frequency range, divide the search frequency range into a plurality of first sub-intervals, and calculate the metric parameter corresponding to each of the first sub-intervals, and obtain the metrics from the plurality of first sub-intervals. Search for the maximum value of the metric parameter in the parameters, and the frequency corresponding to the maximum value;

Reducing the search frequency range to obtain a narrowed search frequency range, determining a new search frequency range according to the frequency and the narrowed search frequency range, and judging whether the current frequency search times is less than the frequency search times;

If it is less than, dividing the new search frequency range into a plurality of second sub-intervals, and calculating the metric parameters corresponding to each of the second sub-intervals, and obtaining the metric parameters from the plurality of second sub-intervals Search for the maximum value of the metric parameter and the frequency corresponding to the maximum value, until the current frequency search times is not less than the frequency search times, the maximum value of the metric parameter and its corresponding frequency searched for the last time are taken as the frequency offset parameter.

Optionally, the parameter estimation unit is specifically used for:

Perform frequency offset processing on the PCMA mixed signal to be processed according to the frequency offset parameter to obtain a PCMA mixed signal after frequency offset removal;

According to the preset operation method, the fourth power operation is performed on the PCMA mixed signal after the frequency offset is removed, and the operation result is simplified to obtain the simplified operation result;

Calculate the phase value of the interference signal according to the simplified operation result.

Optionally, the parameter estimation unit is specifically used for:

Determine the mean value of the simplified operation result and the quadratic mean value of the preset local sequence;

The amplitude value of the interference signal is calculated according to the mean value of the simplified operation result and the fourth power mean value of the preset local sequence.

Optionally, the digital signal processing unit is specifically used for:

Perform down-conversion processing on the PCMA mixed signal to be processed to obtain a zero-IF signal, and perform rate conversion processing on the zero-IF signal to obtain a low-rate PCMA mixed signal;

Filtering the low-rate PCMA mixed signal to obtain a filtered signal, and converting the filtered signal into a digital baseband signal;

Decoding the digital baseband signal to obtain the information bit data and the parity bit data.

Optionally, the reconstruction unit is specifically used for:

generating an interference sequence according to the information bit data and the check bit data;

Demodulating the interference sequence to obtain a demodulated interference sequence, and adjusting the frequency offset, phase and amplitude of the demodulated interference sequence according to the channel parameters to obtain the interference signal.

In a third aspect, the present application provides a computer device, the computer device comprising:

memory for storing instructions executed by at least one processor;

The processor is configured to execute the instructions stored in the memory to execute the method described in the first aspect.

In a fourth aspect, the present application provides a computer-readable storage medium, where computer instructions are stored in the computer-readable storage medium, and when the computer instructions are executed on a computer, the computer causes the computer to execute the method of the first aspect.

Description of drawings

FIG. 1 is a schematic flowchart of a traditional asymmetric PCMA mixed signal processing method provided by an embodiment of the present application;

FIG. 2 is an effect diagram of a traditional asymmetric PCMA mixed signal processing provided by an embodiment of the present application;

3 is a schematic flowchart of a method for processing an asymmetric PCMA mixed signal provided by an embodiment of the present application;

FIG. 4 is a schematic structural diagram of an apparatus for processing an asymmetric PCMA mixed signal provided by an embodiment of the present application;

FIG. 5 is a schematic structural diagram of a computer device according to an embodiment of the present application.

Detailed ways

In the solutions provided in the embodiments of the present application, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

A method for processing an asymmetric PCMA mixed signal provided by the embodiments of the present application will be described in further detail below with reference to the accompanying drawings. The specific implementation of the method may include the following steps (the method flow is shown in FIG. 3 ):

Step 301: Perform parameter estimation on the PCMA mixed signal to be processed to obtain channel parameters, where the PCMA mixed signal to be processed includes a useful signal and an interference signal, and the channel parameters include a frequency offset parameter, a phase parameter of the interference signal, and Amplitude parameter.

In the solution provided by the embodiment of the present application, there are various ways to obtain channel parameters by performing parameter estimation on the PCMA mixed signal to be processed, and a preferred way is used as an example for description below.

In a possible implementation manner, performing parameter estimation on the PCMA mixed signal to be processed to obtain channel parameters includes: performing frequency offset estimation on the PCMA mixed signal to be processed to obtain the frequency offset parameter; The phase parameter is obtained by performing phase estimation on the PCMA mixed signal; the amplitude parameter is obtained by performing amplitude estimation on the PCMA mixed signal to be processed.

In order to facilitate understanding, a brief description of the PCMA mixed signal to be processed is given below.

Suppose that the ground station in the PCMA system receives two MPSK or QAM modulated signals with the same symbol rate, wherein the two signals include the first signal and the second signal, and the sampling interval of the modulated signal is T _s =T/L, L represents the oversampling multiple, then the PCMA mixed signal to be processed is:

Among them, v _k represents the mean value of white Gaussian noise, v _k =0; h ₁ represents the amplitude of the first channel signal; f ₁ represents the frequency offset of the first channel signal; θ ₁ represents the carrier phase of the first channel signal; h ₂ represents the amplitude of the second signal; f ₂ represents the frequency offset of the second signal; θ ₂ represents the carrier phase of the second signal; x _{1, k} represents the digital baseband modulation signal of the useful signal; x _{2, k} represents the interference signal digital baseband modulated signal.

Further, assuming that the modulation modes of the two signals are the same, and the two signals are statistically independent of each other, the digital baseband modulation signal x _1,k or x _2,j can be expressed by the following formula:

Among them, x _i,k represents the ith digital baseband modulation signal, i=1 or 2, k=0,1,...; n={0,1,2,...,L-1}; τ _i represents the ith The timing deviation of the channel signal; a _i,k represents the signal sequence of the i-th channel signal, and its value is related to the modulation method; gi( ) represents the equivalent channel filter, including shaping filter, channel filter and matched filter filter, etc., the effective interval of the filter is [-L ₁ T, L ₁ T], L ₁ represents half the order of the channel filter, m∈[-L ₁ , L ₁ ].

In the solution provided by the embodiment of the present application, the parameter estimation of the PCMA mixed signal to be processed includes three parts: frequency offset estimation, phase estimation and amplitude estimation. In order to facilitate understanding, the processes of frequency offset estimation, phase estimation and amplitude estimation are briefly introduced below.

1. Frequency offset estimation

Specifically, there are many ways to obtain frequency offset parameters by performing frequency offset estimation on the PCMA mixed signal to be processed, and a preferred method is used as an example for description below.

In a possible implementation manner, estimating the frequency offset of the PCMA mixed signal to be processed to obtain the frequency offset parameter includes: setting the frequency search times and the search frequency range, and dividing the search frequency range into multiple The first sub-interval and the metric parameter corresponding to each first sub-interval are calculated, and the maximum value of the metric parameter is searched from the metric parameters of the plurality of first sub-intervals, and the corresponding value of the maximum value is obtained. frequency; reduce the search frequency range to obtain a reduced search frequency range, determine a new search frequency range according to the frequency and the reduced search frequency range, and determine whether the number of current frequency searches is less than the frequency search frequency times; if it is less than, divide the new search frequency range into a plurality of second sub-intervals, and calculate the metric parameter corresponding to each of the second sub-intervals, and calculate the metric parameters from the plurality of second sub-intervals The maximum value of the metric parameter and the frequency corresponding to the maximum value are searched in the parameters, until the current frequency search times is not less than the frequency search times, the maximum value of the metric parameter searched for the last time and its corresponding frequency as the frequency offset parameter.

In order to facilitate the understanding of the above frequency offset estimation process, the following briefly introduces the frequency offset estimation process. Specifically, the steps of frequency offset estimation are as follows:

Step 11: Set the frequency search times q and the frequency search interval S, where q is a positive integer not less than 1; the value range of S is [f _l , f _r ].

第i个子区间的中心频点记为f⁽ⁱ⁾；根据每个子区间的中心频点计算每个子区间对应的R(f⁽ⁱ⁾)值，并将其作为子区间S_i相关值的度量参数。Step 12: Evenly divide the frequency search interval S into M sub-intervals, where M is a positive integer not less than 1; the i-th sub-interval is denoted as S _i , and the frequency range of the i-th sub-interval is:

The central frequency point of the i-th subinterval is denoted as f ⁽ⁱ⁾ ; the corresponding R(f ⁽ⁱ⁾ ) value of each subinterval is calculated according to the central frequency point of each subinterval, and it is used as the measure of the correlation value of the subinterval S _i parameter.

Step 13: Find the maximum value R _max and the frequency point corresponding to R _max from the R(f ⁽ⁱ⁾ ) corresponding to each sub-interval, and denote it as f′.

Step 14: Reduce the size of the interval S to the original 1/M to obtain a new search frequency interval S', where the value range of S' is [f _l ', _fr '],

Step 15, determine whether the frequency search times is less than q; if it is less than, jump to step 12; otherwise, the process ends, and the last determined _Rmax and f' are output as the final search result.

In order to facilitate understanding, a brief introduction to the calculation process of R(f ⁽ⁱ⁾ ) is given below.

根据主站本地发射的本地序列重构干扰信号。具体的，干扰信号的表达式如下所示：Assuming that the delay estimation of the interfering signal has been completed for the PCMA mixed signal to be processed, the delay estimation is

The interfering signal is reconstructed from the local sequence transmitted locally by the primary station. Specifically, the expression of the interference signal is as follows:

Further, delay calibration is performed on the mixed signal according to the estimated delay value, and the following auxiliary signal is constructed:

According to the above _yk expression, the following _zk expression can be obtained:

之间的计算结果：Further, the conjugate function of z _k and s _2,k is expressed by the following formula

Calculation results between:

In the above formula (5), the first item on the right side of the formula is ignored because the two transmission symbols are statistically independent and have frequency offsets, and the correlation is weak; Strong and reserved. Let K represent the length of the relevant symbol, the length of the relevant sampling point N=LK, 0≤K≤N-1, we can get:

Further, we can get:

Obviously, when f=f ₂ , equation (7) takes the maximum value. Therefore, the frequency offset estimation result of the interference signal can be obtained by searching for the peak position of equation (7), that is,

表示频偏参数。in,

Indicates the frequency offset parameter.

2. Phase estimation

Specifically, there are many ways to obtain phase parameters by performing phase estimation on the PCMA mixed signal to be processed, and a preferred way is taken as an example for description below.

In a possible implementation manner, performing phase estimation on the PCMA mixed signal to be processed to obtain the phase parameter includes: performing frequency offset processing on the PCMA mixed signal to be processed according to the frequency offset parameter, Obtain the PCMA mixed signal after frequency offset removal; perform a fourth power operation on the PCMA mixed signal after frequency offset removal according to a preset operation method, and perform simplified processing on the operation result to obtain a simplified operation result; The simplified operation result calculates the phase value of the interference signal.

In order to facilitate the understanding of the above-mentioned phase estimation process, the following briefly introduces the phase estimation process. Specifically, the steps of phase estimation are as follows:

Step 21: Perform frequency offset processing on the PCMA mixed signal to be processed according to the frequency offset parameter to obtain a PCMA mixed signal after frequency offset removal. Specifically, the PCMA mixed signal after frequency offset removal is as follows:

Wherein, Δf ₂ =f ₂ -f; Δf ₁ =f ₁ -f.

Step 22: Perform a fourth power operation on the PCMA mixed signal after frequency offset removal in the above formula (8), and perform simplified processing on the Yunshe result to obtain a simplified operation result. Specifically, the simplified operation result is as follows:

表示本地序列的四次方均值；Among them, E{(z′ _k ) ⁴ } represents the simplified operation result;

represents the quadratic mean of the local sequence;

Step 23: Perform phase estimation on the interference signal according to the simplified operation result to obtain a phase parameter. Specifically, the phase parameter is obtained by estimating the phase of the interference signal by the following formula:

表示相位参数；arg(·)表示复数求相位，取值范围为[-π,π]。in,

Represents the phase parameter; arg(·) represents the complex number to find the phase, and the value range is [-π,π].

3. Amplitude estimation

Specifically, there are many ways to obtain the amplitude parameter by performing amplitude estimation on the PCMA mixed signal to be processed, and a preferred method is used as an example for description below.

In a possible implementation manner, performing amplitude estimation on the PCMA mixed signal to be processed to obtain the amplitude parameter includes: determining the mean value of the simplified operation result and the quadratic mean value of the preset local sequence ; Calculate the amplitude value of the interference signal according to the mean value of the simplified operation result and the quadratic mean value of the preset local sequence.

In order to facilitate the understanding of the above-mentioned amplitude estimation process, the following briefly introduces the amplitude estimation process. Specifically, the steps of amplitude estimation are as follows:

To complete the de-frequency offset of the mixed signal, we can get:

After the mixed signal is de-frequency offset, the fourth power operation is performed, and the calculation result is simplified to get

两边取模得到简化后的运算结果的均值

令本地序列的四次方均值

为常数G。Step 31, the simplified operation result

Take the modulo on both sides to get the mean of the simplified operation result

Let the quartic mean of the local series

is the constant G.

以及常数G计算得到干扰信号的幅度值。具体的，通过如下公式计算干扰信号的幅度值：Step 32, according to the mean value of the simplified operation result

And the constant G is calculated to obtain the amplitude value of the interference signal. Specifically, the amplitude value of the interference signal is calculated by the following formula:

表示干扰信号的幅度值。in,

Indicates the amplitude value of the interfering signal.

Step 302: Perform digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and check bit data.

In the solution provided by the embodiment of the present application, there are many ways to perform digital signal processing on the PCMA mixed signal to be processed to obtain the information bit data and the check bit data. The following takes a preferred way as an example. illustrate.

In a possible implementation manner, performing digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and parity bit data includes: performing down-conversion processing on the PCMA mixed signal to be processed to obtain a zero intermediate frequency performing rate conversion processing on the zero-IF signal to obtain a low-rate PCMA mixed signal; filtering the low-rate PCMA mixed signal to obtain a filtered signal, and converting the filtered signal into a digital baseband signal; The digital baseband signal is decoded to obtain the information bit data and the check bit data.

Specifically, the received PCMA mixed signal sent by the transmitter is down-converted to a zero-IF signal, and then the low-pass filter tap coefficients are generated by matlab, and the FIR core of Xilinx is called to realize sampling rate conversion to obtain a low-rate PCMA mixed signal, and then The low-rate PCMA mixed signal is filtered to obtain a filtered signal, and the filtered signal is converted into a digital baseband signal, and then the digital baseband signal is subjected to low density parity check (Low Density Parity Check Code, LDPC) Decoding obtains information bit data and check bit data.

Step 303: Perform reconstruction according to the channel parameters, the information bit data and the check bit data to generate the interference signal, and subtract the PCMA mixed signal to be processed and the interference signal to obtain the useful signal. Signal.

In a possible implementation manner, performing reconstruction to generate the interference signal according to the channel parameter, the information bit data and the check bit data includes: according to the information bit data and the check bit data generating an interference sequence from the data; demodulating the interference sequence to obtain a demodulated interference sequence, and adjusting the frequency offset, phase and amplitude of the demodulated interference sequence according to the channel parameters to obtain the interference signal.

In the solution provided by the embodiment of the present application, the signal bit data and check bit data obtained by decoding are used to reconstruct the interference sequence directly in the process of reconstructing the interference signal. Therefore, coding is not required in the process of generating the interference sequence, which reduces the need for coding. The difficulty of reconstructing the interference signal makes it easier to eliminate the interference signal in the PCMA mixed signal.

Specifically, an interference sequence is generated according to the decoded information bit data and check bit data, then the interference sequence is encoded and modulated, and the frequency offset, phase and amplitude of the interference sequence are adjusted and reconstructed according to the estimated channel parameters. generate interfering signals. The useful signal is obtained by subtracting the PCMA mixed signal to be processed and the interference signal.

In the solution provided by the embodiment of the present application, the PCMA mixed signal to be processed is subjected to parameter estimation to obtain channel parameters, and the PCMA mixed signal to be processed is subjected to digital signal processing to obtain information bit data and parity bit data. The parameters, the information bit data and the check bit data are reconstructed to generate the interference signal, and the useful signal is obtained by subtracting the PCMA mixed signal to be processed and the interference signal. Therefore, in the solution provided by the embodiment of the present application, the interference signal is reconstructed according to the information bit data and check bit data obtained by decoding the PCMA mixed signal and the channel parameters estimated by the PCMA mixed signal, so the interference signal is closer to PCMA The actual interference signal in the mixed signal, thereby improving the effect of eliminating the interference signal in the PCMA mixed signal.

Based on the same inventive concept as the method shown in FIG. 3, an embodiment of the present application provides an apparatus for processing an asymmetric PCMA mixed signal. Referring to FIG. 4, the apparatus includes:

A parameter estimation unit 401, configured to perform parameter estimation on a PCMA mixed signal to be processed to obtain a channel parameter, wherein the PCMA mixed signal to be processed includes a useful signal and an interference signal, and the channel parameter includes a frequency offset parameter of the interference signal , phase parameters and amplitude parameters;

a digital signal processing unit 402, configured to perform digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and check bit data;

Reconstruction unit 403, configured to reconstruct and generate the interference signal according to the channel parameter, the information bit data and the check bit data, and subtract the PCMA mixed signal to be processed from the interference signal The useful signal is obtained.

Optionally, the parameter estimation unit 401 is specifically configured to:

Perform frequency offset estimation on the PCMA mixed signal to be processed to obtain the frequency offset parameter;

performing phase estimation on the PCMA mixed signal to be processed to obtain the phase parameter;

The amplitude parameter is obtained by performing amplitude estimation on the PCMA mixed signal to be processed.

Optionally, the parameter estimation unit 401 is specifically configured to:

Set the frequency search times and the search frequency range, divide the search frequency range into a plurality of first sub-intervals, and calculate the metric parameter corresponding to each of the first sub-intervals, and obtain the metrics from the plurality of first sub-intervals. Search for the maximum value of the metric parameter in the parameters, and the frequency corresponding to the maximum value;

Reducing the search frequency range to obtain a narrowed search frequency range, determining a new search frequency range according to the frequency and the narrowed search frequency range, and judging whether the current frequency search times is less than the frequency search times;

If it is less than, dividing the new search frequency range into a plurality of second sub-intervals, and calculating the metric parameters corresponding to each of the second sub-intervals, and obtaining the metric parameters from the plurality of second sub-intervals Search for the maximum value of the metric parameter and the frequency corresponding to the maximum value, until the current frequency search times is not less than the frequency search times, the maximum value of the metric parameter and its corresponding frequency searched for the last time are taken as the frequency offset parameter.

Optionally, the parameter estimation unit 401 is specifically configured to:

Perform frequency offset processing on the PCMA mixed signal to be processed according to the frequency offset parameter to obtain a PCMA mixed signal after frequency offset removal;

According to the preset operation method, the fourth power operation is performed on the PCMA mixed signal after the frequency offset is removed, and the operation result is simplified to obtain the simplified operation result;

Calculate the phase value of the interference signal according to the simplified operation result.

Optionally, the parameter estimation unit 401 is specifically configured to:

Determine the mean value of the simplified operation result and the quadratic mean value of the preset local sequence;

The amplitude value of the interference signal is calculated according to the mean value of the simplified operation result and the fourth power mean value of the preset local sequence.

Optionally, the digital signal processing unit 402 is specifically configured to:

Perform down-conversion processing on the PCMA mixed signal to be processed to obtain a zero-IF signal, and perform rate conversion processing on the zero-IF signal to obtain a low-rate PCMA mixed signal;

Filtering the low-rate PCMA mixed signal to obtain a filtered signal, and converting the filtered signal into a digital baseband signal;

Decoding the digital baseband signal to obtain the information bit data and the parity bit data.

Optionally, the reconstruction unit 403 is specifically configured to:

generating an interference sequence according to the information bit data and the check bit data;

Demodulating the interference sequence to obtain a demodulated interference sequence, and adjusting the frequency offset, phase and amplitude of the demodulated interference sequence according to the channel parameters to obtain the interference signal.

Referring to FIG. 5, the present application provides a computer device, the computer device includes:

a memory 501 for storing instructions executed by at least one processor;

The processor 502 is configured to execute the instructions stored in the memory to execute the method described in FIG. 3 .

The present application provides a computer-readable storage medium, where computer instructions are stored in the computer-readable storage medium, and when the computer instructions are executed on a computer, the computer can execute the method described in FIG. 3 .

As will be appreciated by those skilled in the art, the embodiments of the present application may be provided as a method, a system, or a computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media having computer-usable program code embodied therein, including but not limited to disk storage, optical storage, and the like.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims (4)

1. A method for processing an asymmetric PCMA hybrid signal, comprising:

performing parameter estimation on a to-be-processed PCMA mixed signal to obtain a channel parameter, wherein the to-be-processed PCMA mixed signal comprises a useful signal and an interference signal, and the channel parameter comprises a frequency offset parameter, a phase parameter and an amplitude parameter of the interference signal;

carrying out digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and check bit data;

Reconstructing according to the channel parameter, the information bit data and the check bit data to generate the interference signal, and subtracting the to-be-processed PCMA mixed signal from the interference signal to obtain the useful signal;

the method for obtaining the channel parameters by performing parameter estimation on the PCMA mixed signal to be processed comprises the following steps:

carrying out frequency offset estimation on the PCMA mixed signal to be processed to obtain the frequency offset parameter;

performing phase estimation on the PCMA mixed signal to be processed to obtain the phase parameter;

carrying out amplitude estimation on the PCMA mixed signal to be processed to obtain the amplitude parameter;

performing frequency offset estimation on the to-be-processed PCMA mixed signal to obtain the frequency offset parameter, including:

setting frequency searching times and a searching frequency range, dividing the searching frequency range into a plurality of first sub-intervals, calculating a measurement parameter corresponding to each first sub-interval, and searching out the maximum value of the measurement parameter and the frequency corresponding to the maximum value from the measurement parameters of the plurality of first sub-intervals;

narrowing the search frequency range to obtain a narrowed search frequency range, determining a new search frequency range according to the frequency and the narrowed search frequency range, and judging whether the current frequency search frequency is less than the frequency search frequency;

If the frequency offset parameter is less than the first frequency offset parameter, dividing the new search frequency range into a plurality of second sub-intervals, calculating a measurement parameter corresponding to each second sub-interval, searching a maximum value of the measurement parameter and a frequency corresponding to the maximum value from the measurement parameters of the plurality of second sub-intervals until the current frequency search frequency is not less than the frequency search frequency, and taking the maximum value of the measurement parameter searched for the last time and the frequency corresponding to the maximum value as the frequency offset parameter;

performing phase estimation on the PCMA mixed signal to be processed to obtain the phase parameter, including:

carrying out frequency deviation removal processing on the PCMA mixed signal to be processed according to the frequency deviation parameters to obtain the PCMA mixed signal subjected to frequency deviation removal;

performing a quadratic operation on the PCMA mixed signal subjected to frequency offset removal according to a preset operation method, and simplifying an operation result to obtain a simplified operation result;

calculating a phase value of the interference signal according to the simplified operation result;

performing amplitude estimation on the to-be-processed PCMA mixed signal to obtain the amplitude parameter, including:

determining the mean value of the simplified operation result and the fourth power mean value of a preset local sequence;

Calculating the amplitude value of the interference signal according to the mean value of the simplified operation result and the fourth power mean value of the preset local sequence;

performing digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and check bit data, including:

carrying out down-conversion processing on the PCMA mixed signal to be processed to obtain a zero intermediate frequency signal, and carrying out rate conversion processing on the zero intermediate frequency signal to obtain a low-rate PCMA mixed signal;

filtering the low-rate PCMA mixed signal to obtain a filtered signal, and converting the filtered signal into a digital baseband signal;

decoding the digital baseband signal to obtain the information bit data and the check bit data;

reconstructing according to the channel parameter, the information bit data and the check bit data to generate the interference signal, including:

generating an interference sequence according to the information bit data and the check bit data;

and demodulating the interference sequence to obtain a demodulated interference sequence, and adjusting frequency offset, phase and amplitude of the demodulated interference sequence according to the channel parameters to obtain the interference signal.

2. An apparatus for processing an asymmetric PCMA hybrid signal, comprising:

the device comprises a parameter estimation unit, a channel estimation unit and a processing unit, wherein the parameter estimation unit is used for performing parameter estimation on a to-be-processed PCMA mixed signal to obtain a channel parameter, the to-be-processed PCMA mixed signal comprises a useful signal and an interference signal, and the channel parameter comprises a frequency offset parameter, a phase parameter and an amplitude parameter of the interference signal;

the digital signal processing unit is used for carrying out digital signal processing on the PCMA mixed signal to be processed to obtain information bit data and check bit data;

and the reconstruction unit is used for reconstructing according to the channel parameters, the information bit data and the check bit data to generate the interference signal, and subtracting the interference signal from the PCMA mixed signal to be processed to obtain the useful signal.

3. The apparatus of claim 2, wherein the parameter estimation unit is specifically configured to:

performing frequency offset estimation on the PCMA mixed signal to be processed to obtain the frequency offset parameter;

performing phase estimation on the PCMA mixed signal to be processed to obtain the phase parameter;

and carrying out amplitude estimation on the PCMA mixed signal to be processed to obtain the amplitude parameter.

4. The apparatus according to claim 3, wherein the reconstruction unit is specifically configured to:

generating an interference sequence according to the information bit data and the check bit data;

and demodulating the interference sequence to obtain a demodulated interference sequence, and adjusting frequency offset, phase and amplitude of the demodulated interference sequence according to the channel parameters to obtain the interference signal.

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