Compressive sensing channel estimation method and device based on PN correlation threshold path search

Abstract

The application provides a compressed sensing channel estimation method and device based on a PN correlation threshold path search. The method comprises: performing correlation matching processing on an original reference signal and a PN sequence to obtain a plurality of matching values; selecting atoms satisfying a condition from a sensing matrix according to the plurality of matching values, that is, performing correlation matching processing on the original reference signal and the PN sequence by using the sharp autocorrelation characteristics of the PN sequence, and selecting atoms based on the matching values obtained by the matching processing to suppress non-ideal atoms caused by noise, so as to screen the atoms in the OMP algorithm reconstruction process, and finally obtain a reference signal without clutter. Since the method of the application is a purification method for the received original reference signal, the hardware system does not need to be processed, so the system requirement is reduced. In addition, the method of the application avoids the problem of multi-path signals entering the beam when the propagation environment is relatively complex, thereby improving the purity of the original reference signal.

Description

Technical Field

[0001] This invention relates to the field of external radiation source radar data processing technology, specifically to a compressed sensing channel estimation method and apparatus based on PN correlation threshold pathfinding. Background Technology

[0002] External radiation source radars typically have two channels: a reference channel and a monitoring channel. Due to the reflection effects of mountains and nearby buildings, the reference channel of an external radiation source radar is inevitably affected by multipath interference. If the signals from both channels are directly used for cross-correlation processing, multiple false targets will appear, masking the real target. To eliminate the effects of multipath and Doppler spread caused by the transmission environment, the direct wave signal (reference signal) of the reference channel must be purified at the receiving end.

[0003] Traditional reference signal purification for external radiation source radars typically aims to minimize the entry of multipath signals into the reference channel when receiving direct waves. This is generally achieved through methods such as using a highly directional antenna to beamform the multipath signals received by the transmitting station or a co-located array antenna for reference and monitoring, thus directing the beam towards the transmitting station. These methods place high demands on the system, and when the propagation environment is complex, multipath signals may still enter the beam, making it difficult to guarantee the purity of the reference signal.

[0004] Therefore, existing methods for purifying reference signals from external radiation source radars have problems such as high system requirements and difficulty in guaranteeing signal purity. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, this invention provides a compressed sensing channel estimation method and apparatus based on PN correlation threshold pathfinding.

[0006] The technical problem to be solved by this invention is achieved through the following technical solution:

[0007] In a first aspect, the present invention provides a compressed sensing channel estimation method based on PN correlation threshold pathfinding, comprising:

[0008] The original reference signal and the PN sequence generated during the transmission of the signal are obtained by acquiring the transmission signal emitted by the transmitting station.

[0009] Correlation matching processing is performed on the original reference signal and the PN sequence to obtain multiple matching values;

[0010] Atoms that meet the conditions are selected from the perception matrix based on multiple matching values, and the initial prior atom set is updated based on the atoms that meet the conditions to obtain the prior atom set;

[0011] Channel response coefficients are calculated based on the prior atom set and the OMP algorithm to obtain channel estimation results;

[0012] A multipath filter is generated based on the channel estimation results, and the original reference signal is reconstructed under the action of the multipath filter to obtain a reference signal without clutter.

[0013] Optionally, the original reference signal is represented as:

[0014]

[0015] Where, r pn (n) represents the original reference signal, K represents the total number of multipaths in the channel, and α k Let represent the amplitude of the k-th multipath in the channel, s(n) represent the transmitted signal, s(nk) represent the nk-th sample value of the transmitted signal, and ω(n) represent Gaussian white noise.

[0016] Optionally, correlation matching processing is performed on the original reference signal and the PN sequence to obtain multiple matching values, including:

[0017] Based on the original reference signal and the PN sequence, correlation is calculated using the following formula to obtain multiple matching values:

[0018]

[0019] Among them, R pr (n) represents the matched value, L tap Let p(i) represent the channel response length, p(i) represent the PN sequence, i represent the i-th channel response length, and r represent the channel response length. pn (n+i) represents the (n+i)th sample value of the original reference signal, s(n+ik) represents the (n+ik)th sample value of the transmitted signal, ω(n+i) represents the (n+i)th sample value of the Gaussian white noise, and n represents the nth sample value.

[0020] Optionally, atoms that meet the conditions are selected from the perception matrix based on multiple matching values, and the initial prior atom set is updated based on the atoms that meet the conditions to obtain the prior atom set, including:

[0021] Initialize the atom set to obtain the initial prior atom set;

[0022] The mean of all matching values ​​is calculated to obtain the relevant mean.

[0023] The column vectors of the perception matrix that are greater than the relevant mean are extracted and stored as atoms that meet the conditions in the initial prior atom set to form the prior atom set; the perception matrix is ​​constructed based on the shifting process of the PN sequence.

[0024] Optionally, the channel response coefficients are calculated based on the prior atom set and the OMP algorithm to obtain the channel estimation results, including:

[0025] S201. Initialize iteration parameters;

[0026] S202. Calculate the correlation between the residuals in the iteration parameters and the perception matrix to obtain the correlation value;

[0027] S203. Obtain the atom index θ corresponding to the relevant value from the perception matrix. i and the columns corresponding to the perception matrix

[0028] S204, if the atom index θ i If there is an intersection with the prior set of atoms, then update the iteration parameters to obtain the current iteration parameters;

[0029] S205. Determine whether the current iteration parameters meet the preset threshold and obtain the determination result;

[0030] S206. Based on the judgment result and the current iteration parameters, obtain the channel estimation result.

[0031] Optionally, the iteration parameters include: number of iterations, residual, index set, and optimal atom set.

[0032] Optionally, if the atom index intersects with the prior atom set, the iteration parameters are updated to obtain the current iteration parameters, including:

[0033] If an atomic index intersects with the prior atomic set, then the atomic index that intersects with the prior atomic set is added to the current index set and the current optimal atomic set, and the current index set and the current optimal atomic set are used as the current iteration parameters.

[0034] Optionally, based on the judgment result and the current iteration parameters, the channel estimation result is obtained, including:

[0035] If the current iteration number in the current iteration parameter is less than the iteration threshold, then the current iteration parameter is used as the iteration parameter in S202;

[0036] Repeat steps S202-S205 until the current iteration number in the current iteration parameter is greater than the iteration threshold.

[0037] The channel response coefficients are calculated using the current iteration parameters that are greater than the iteration threshold, and the channel estimation results are obtained.

[0038] In a second aspect, the present invention provides a compressed sensing channel estimation device based on PN correlation threshold pathfinding, comprising: an acquisition unit, a calculation unit, a selection unit, and a reconstruction unit;

[0039] The acquisition unit is used to: acquire the transmission signal emitted by the transmitting station and the PN sequence generated during the transmission of the signal, and obtain the original reference signal and the PN sequence;

[0040] The calculation unit is used to: perform correlation matching processing on the original reference signal and the PN sequence to obtain multiple matching values;

[0041] The selection unit is used to: select atoms that meet the conditions from the perception matrix based on multiple matching values, and update the initial prior atom set based on the atoms that meet the conditions to obtain the prior atom set;

[0042] The computing unit is also used to: calculate the channel response coefficients based on the prior atom set and the OMP algorithm to obtain the channel estimation results;

[0043] The reconstruction unit is used to: generate a multipath filter based on the channel estimation results, and perform signal reconstruction processing on the original reference signal under the action of the multipath filter to obtain a reference signal without clutter.

[0044] Thirdly, the present invention provides a compressed sensing channel estimation device based on PN-related threshold pathfinding, comprising: a processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor, and when the compressed sensing channel estimation device based on PN-related threshold pathfinding is running, the processor communicates with the storage medium via the bus, and the processor executes the machine-readable instructions to perform the steps of the compressed sensing channel estimation method based on PN-related threshold pathfinding described in the first aspect above.

[0045] This invention provides a compressed sensing channel estimation method and apparatus based on PN correlation threshold pathfinding. The compressed sensing channel estimation method based on PN correlation threshold pathfinding includes: acquiring a transmitted signal from a transmitting station and a PN sequence generated during the transmission of the signal, obtaining an original reference signal and a PN sequence; performing correlation matching processing on the original reference signal and the PN sequence to obtain multiple matching values; selecting atoms that meet certain conditions from a sensing matrix based on the multiple matching values, and updating an initial prior atom set based on the atoms that meet the conditions, obtaining a prior atom set; calculating the channel response coefficient based on the prior atom set and the OMP algorithm to obtain a channel estimation result; generating a multipath filter based on the channel estimation result, and performing signal reconstruction processing on the original reference signal under the action of the multipath filter to obtain a clutter-free reference signal. In this invention, the sharp autocorrelation characteristics of the PN sequence are utilized to perform correlation matching processing on the original reference signal and the PN sequence, and atom selection is performed based on the matching values ​​obtained from the matching processing to suppress non-ideal atoms caused by noise, thereby filtering atoms in the OMP algorithm reconstruction process and finally obtaining a clutter-free reference signal. Since the method of this invention purifies the received original reference signal, no hardware processing is required, thus reducing system requirements. In addition, the method of this invention avoids the problem of multipath signals entering the beam when the propagation environment is complex, thereby improving the purity of the original reference signal.

[0046] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0047] Figure 1 A flowchart illustrating a compressed sensing channel estimation method based on PN correlation threshold pathfinding provided in an embodiment of the present invention;

[0048] Figure 2 The channel estimation value based on the method of the present invention is provided in the embodiments of the present invention;

[0049] Figure 3 The channel estimation value based on the LS method provided in the embodiments of the present invention;

[0050] Figure 4 The channel estimation value based on the traditional OMP method provided in the embodiments of the present invention;

[0051] Figure 5 The channel estimation value based on the DFT method provided in the embodiments of the present invention;

[0052] Figure 6 A schematic diagram of a compressed sensing channel estimation device based on PN correlation threshold pathfinding provided in an embodiment of the present invention;

[0053] Figure 7 This is a schematic diagram of a compressed sensing channel estimation device based on PN correlation threshold pathfinding, provided in an embodiment of the present invention. Detailed Implementation

[0054] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0055] To address the issues of high system requirements and difficulty in guaranteeing the purity of the original reference signal in existing external radiation source radar purification methods, this invention provides a compressed sensing channel estimation method based on PN correlation threshold pathfinding. Figure 1 This is a flowchart illustrating a compressed sensing channel estimation method based on PN correlation threshold pathfinding, provided in an embodiment of the present invention. Figure 1 ,include:

[0056] S101. Obtain the transmission signal emitted by the transmitting station and the PN sequence generated when transmitting the transmission signal to obtain the original reference signal and the PN sequence.

[0057] Optionally, the original reference signal is represented as:

[0058]

[0059] Where, r pn (n) represents the original reference signal, K represents the total number of multipaths in the channel, and α k Let represent the amplitude of the k-th multipath in the channel, s(n) represent the transmitted signal, s(nk) represent the nk-th sample value of the transmitted signal, and ω(n) represent Gaussian white noise.

[0060] S102. Perform correlation matching processing on the original reference signal and PN sequence to obtain multiple matching values.

[0061] Optionally, S102 may specifically include:

[0062] Based on the original reference signal and the PN sequence, correlation is calculated using the following formula to obtain multiple matching values:

[0063]

[0064] Among them, R pr (n) represents the matched value, L tap Let p(i) represent the channel response length, p(i) represent the PN sequence, i represent the i-th channel response length, and r represent the channel response length. pn(n+i) represents the (n+i)th sample value of the original reference signal, s(n+ik) represents the (n+ik)th sample value of the transmitted signal, ω(n+i) represents the (n+i)th sample value of the Gaussian white noise, and n represents the nth sample value.

[0065] S103. Select atoms that meet the conditions from the perception matrix based on multiple matching values, and update the initial prior atom set based on the atoms that meet the conditions to obtain the prior atom set.

[0066] Optionally, S103 may specifically include:

[0067] Initialize the atom set to obtain the initial prior atom set;

[0068] The mean of all matching values ​​is calculated to obtain the relevant mean.

[0069] The column vectors of the perception matrix that are greater than the relevant mean are extracted and stored as atoms that meet the conditions in the initial prior atom set to form the prior atom set; the perception matrix is ​​constructed based on the shifting process of the PN sequence.

[0070] S104. Calculate the channel response coefficients based on the prior atom set and the OMP algorithm to obtain the channel estimation results.

[0071] Optionally, S104 may specifically include:

[0072] S201. Initialize iteration parameters;

[0073] S202. Calculate the correlation between the residuals in the iteration parameters and the perception matrix to obtain the correlation value;

[0074] S203. Obtain the atom index θ corresponding to the relevant value from the perception matrix. i and the columns corresponding to the perception matrix

[0075] S204, if the atom index θ i If there is an intersection with the prior set of atoms, then update the iteration parameters to obtain the current iteration parameters;

[0076] S205. Determine whether the current iteration parameters meet the preset threshold and obtain the determination result;

[0077] S206. Based on the judgment result and the current iteration parameters, obtain the channel estimation result.

[0078] Optionally, the iteration parameters include: number of iterations, residual, index set, and optimal atom set.

[0079] Optionally, S204 may specifically include:

[0080] If an atomic index intersects with the prior atomic set, then the atomic index that intersects with the prior atomic set is added to the current index set and the current optimal atomic set, and the current index set and the current optimal atomic set are used as the current iteration parameters.

[0081] Optionally, S206 may specifically include:

[0082] If the current iteration number in the current iteration parameter is less than the iteration threshold, then the current iteration parameter is used as the iteration parameter in S202;

[0083] Repeat steps S202-S205 until the current iteration number in the current iteration parameter is greater than the iteration threshold.

[0084] The channel response coefficients are calculated using the current iteration parameters that are greater than the iteration threshold, and the channel estimation results are obtained.

[0085] In this embodiment of the invention, the process of generating channel estimation results based on prior atom sets is illustrated as follows:

[0086] 1. When the prior atom set is pre_set, initialize the iteration parameters;

[0087] Initialize the number of iterations l = 1.

[0088] Initialize the residual w0 to equal the observation vector y.

[0089] y = [x FH (L tap -1),x FH (L tap ),...x FH (L pn -1)] T ;

[0090] Where, x FH This is the frame header portion of the original reference signal, where T represents transpose and L... pn Indicates the length of the PN protection interval.

[0091] Initialize index set Optimal Atom Set

[0092] 2. Update the index set Θ at the l-th iteration. l The optimal atom set Ψ at the l-th iteration l .

[0093] Sub-step 2a, calculate the correlation value cor=|Ξ H w l-1 | Obtain the atomic index θ corresponding to the maximum value in cor during the l-th iteration. l and the columns corresponding to the perception matrix H represents the conjugate transpose.

[0094] Where Ξ is the perception matrix, composed of a series of row vectors after linear shift of the PN sequence, w l-1 This represents the residual at the (l-1)th iteration.

[0095] Sub-step 2b, if θ l It intersects with the a priori set of atoms, that is Then update the index set and the optimal atom set.

[0096] Θ l =Θ l-1 ∪θ l ;

[0097]

[0098] Θ l-1 Ψ represents the index set before the update. l This represents the optimal set of atoms before the update.

[0099] Step 3: By solving the following minimization Norm optimization problems can effectively reconstruct sparse channel responses.

[0100]

[0101] In the formula, Let ||·||0 represent the sparse channel response to be estimated (channel estimation result), and let ||·||0 represent the zero norm.

[0102] The least squares solution is used as the channel response coefficient for the l-th iteration.

[0103]

[0104] Step 4: Update residual w l Calculate the accuracy α of residual change l .

[0105]

[0106] α l =|w l-1 -w l | / |w l |;

[0107] Step 5: Update the iteration count, that is, increment the current iteration count by 1 to get the current iteration count, if l > K or α l If <β, terminate the iteration and output the channel estimation result. Otherwise, return to step 2.

[0108] β represents the iteration termination threshold.

[0109] S105. Generate a multipath filter based on the channel estimation results, and perform signal reconstruction processing on the original reference signal under the action of the multipath filter to obtain a reference signal without clutter.

[0110] This invention provides a compressed sensing channel estimation method based on PN correlation threshold pathfinding. Utilizing the sharp autocorrelation characteristics of the PN sequence, correlation matching is performed on the original reference signal and the PN sequence. Atom selection is then performed based on the matching values ​​obtained to suppress noise-induced non-ideal atoms, thus filtering atoms during the OMP algorithm reconstruction process and ultimately obtaining a clutter-free reference signal. Since this method purifies the received original reference signal without requiring hardware processing, system requirements are reduced. Furthermore, this method avoids the problem of multipath signals entering the beam when the propagation environment is complex, thereby improving the purity of the original reference signal.

[0111] It is understood that, in the embodiments of the present invention, by improving the purity of the original reference signal, the accuracy of the final obtained real target is improved when cross-correlation processing is performed using the signals from the reference and monitoring channels.

[0112] To verify the accuracy of the compressed sensing channel estimation method based on PN correlation threshold pathfinding provided in this embodiment of the invention, simulation verification was also conducted. This embodiment used a series of simulation experiments to verify the effectiveness of the method. For performance comparison, four commonly used channel estimation methods were reproduced: the method of this invention, the LS method, the traditional OMP method, and the DFT method. The simulation parameters of the original reference signal strictly followed the DTMB transmit signal standard definition, as shown in Table 1. Some parameter settings of the external radiation source radar system are shown in Table 2. Furthermore, the simulation experiment selected the typical urban broadcast channel model, the Brazil-A channel, to simulate the wireless transmission channel in the actual system. The attenuation and delay parameters of the Brazil-A channel are shown in Table 3, and it can be observed that the sparsity of the channel is 6. It is assumed that each multipath is subject to independent Rayleigh fading effects, and all multipath fading has been normalized. It should be noted that before channel estimation, it is necessary to ensure that the original reference signal has been accurately synchronized.

[0113] Table 1 Simulation signal parameter settings

[0114] Parameter type Symbolic representation Parameter value carrier frequency <![CDATA[f c ]]> 666MHz Sampling rate <![CDATA[f s ]]> 7.56MHz Number of subcarriers C 3780 Subcarrier spacing Δf 2kHz Symbol rate 1 / T 7.56 Msps Frame header mode - PN420 Modulation method - 4QAM signal bandwidth B 7.56MHz

[0115] Table 2. Simulation parameter settings for the external radiation source radar system.

[0116] Parameter type symbol Value Transmit power <![CDATA[P t ]]> 1kW Transmit antenna gain <![CDATA[G t ]]> 1dB Receive antenna gain <![CDATA[G r ]]> 20dB Receiver temperature T 35℃ Receiver bandwidth <![CDATA[B r ]]> 8MHz

[0117] Table 3 Channel Model Parameter Settings

[0118]

[0119] Figure 2 The channel estimation value based on the method of the present invention is provided for embodiments of the present invention. Figure 3 The channel estimation value based on the LS method is provided in the embodiments of the present invention. Figure 4 The channel estimation value based on the traditional OMP method is provided for the embodiments of the present invention. Figure 5 The channel estimation value based on the DFT method provided in this embodiment of the invention. Figure 2 It can be seen that the channel estimation values ​​obtained based on the method of this invention are in high agreement with the actual channel attenuation and delay positions. From Figures 3-5 The channel estimates obtained by these methods all differ to varying degrees from the ideal channel estimates.

[0120] Therefore, the simulation results above verify the effectiveness of the method of the present invention, which can obtain more accurate and robust channel response compared with other methods.

[0121] The method provided in this embodiment of the invention can be applied to electronic devices. Specifically, the electronic device can be a desktop computer, a portable computer, a smart mobile terminal, a server, etc., and this embodiment of the invention does not limit the application to such devices.

[0122] Based on the same inventive concept, embodiments of the present invention also provide a compressed sensing channel estimation device based on PN correlation threshold pathfinding. Figure 6 This is a schematic diagram of a compressed sensing channel estimation device based on PN correlation threshold pathfinding, provided as an embodiment of the present invention. Figure 6 As shown, it includes: an acquisition unit 601, a calculation unit 602, a selection unit 603, and a reconstruction unit 604;

[0123] The acquisition unit 601 is used to: acquire the transmission signal emitted by the transmitting station and the PN sequence generated when the transmission signal is emitted, and obtain the original reference signal and the PN sequence;

[0124] The calculation unit 602 is used to: perform correlation matching processing on the original reference signal and the PN sequence to obtain multiple matching values;

[0125] The selection unit 603 is used to: select atoms that meet the conditions from the perception matrix based on multiple matching values, and update the initial prior atom set based on the atoms that meet the conditions to obtain the prior atom set;

[0126] The calculation unit 602 is also used to: calculate the channel response coefficients based on the prior atom set and the OMP algorithm to obtain the channel estimation result;

[0127] The reconstruction unit 604 is used to: generate a multipath filter based on the channel estimation results, and perform signal reconstruction processing on the original reference signal under the action of the multipath filter to obtain a reference signal without clutter.

[0128] Figure 7 This invention provides a schematic diagram of a compressed sensing channel estimation device based on PN correlation threshold pathfinding, comprising: a processor 710, a storage medium 720, and a bus 730. The storage medium 720 stores machine-readable instructions executable by the processor 710. When the compressed sensing channel estimation device based on PN correlation threshold pathfinding is running, the processor 710 communicates with the storage medium 720 via the bus 730, and the processor 710 executes the machine-readable instructions to perform the steps of the above-described method embodiment. Specific implementations and technical effects are similar and will not be repeated here.

[0129] The storage medium may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the storage medium may also be at least one storage device located remotely from the aforementioned processor.

[0130] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0131] It should be noted that the terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention.

[0132] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0133] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art, by reviewing the accompanying drawings and the disclosure, will understand and implement other variations of the disclosed embodiments in carrying out the claimed invention. In the description of the invention, the word "comprising" does not exclude other components or steps, "a" or "an" does not exclude a plurality, and "a plurality" means two or more, unless otherwise explicitly specified. Furthermore, while different embodiments may describe certain measures, this does not mean that these measures cannot be combined to produce good results.

[0134] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the inventive concept, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A compressed sensing channel estimation method based on PN correlation threshold pathfinding, characterized in that, include: The original reference signal and the PN sequence are obtained by acquiring the transmission signal emitted by the transmitting station and the PN sequence generated when the transmission signal is emitted. The original reference signal and the PN sequence are subjected to correlation matching processing to obtain multiple matching values; Atoms that meet the conditions are selected from the perception matrix based on the multiple matching values, and the initial prior atom set is updated based on the atoms that meet the conditions to obtain the prior atom set; the perception matrix is ​​constructed based on the shifting process of the PN sequence; Channel response coefficients are calculated based on the aforementioned prior atom set and the OMP algorithm to obtain channel estimation results; A multipath filter is generated based on the channel estimation results, and the original reference signal is reconstructed under the action of the multipath filter to obtain a reference signal without clutter. The correlation matching process performed on the original reference signal and the PN sequence yields multiple matching values, including: Based on the original reference signal and the PN sequence, the correlation is calculated using the following formula to obtain the multiple matching values: ； in, Indicates the matching value. Indicates the channel response length. Represents a PN sequence. Indicates the first Each channel response length, The first part represents the original reference signal. Each sample value, The number of transmitted signals Each sample value, The first digit represents Gaussian white noise. Each sample value, Indicates the first Each sample value; The process of calculating the channel response coefficients based on the prior atom set and the OMP algorithm to obtain the channel estimation result includes: S201. Initialize iteration parameters; S202. Calculate the correlation between the residual in the iteration parameters and the perception matrix to obtain the correlation value; S203. Obtain the atom index corresponding to the relevant value from the perception matrix. and the columns corresponding to the perception matrix ; S204, if the atomic index If there is an intersection with the prior atom set, the iteration parameters are updated to obtain the current iteration parameters; S205. Determine whether the current iteration parameter meets the preset threshold, and obtain the determination result; S206. Based on the judgment result and the current iteration parameters, obtain the channel estimation result.

2. The compressed sensing channel estimation method based on PN correlation threshold pathfinding according to claim 1, characterized in that, The original reference signal is represented as follows: ； in, This refers to the original reference signal. This represents the total number of multipaths present in the channel. Indicates the first in the channel The amplitude of the multi-path, Indicates the transmission of a signal. The number of transmitted signals Each sample value, This represents Gaussian white noise.

3. The compressed sensing channel estimation method based on PN correlation threshold pathfinding according to claim 1, characterized in that, The step of selecting atoms that meet the conditions from the perception matrix based on the multiple matching values, and updating the initial prior atom set based on the atoms that meet the conditions to obtain the prior atom set includes: Initialize the atom set to obtain the initial prior atom set; The mean of all the matching values ​​is calculated to obtain the relevant mean. The column vectors of the perception matrix that are greater than the relevant mean are extracted and stored as atoms that meet the conditions in the initial prior atom set to form the prior atom set.

4. The compressed sensing channel estimation method based on PN correlation threshold pathfinding according to claim 1, characterized in that, The iteration parameters include: number of iterations, residual, index set, and optimal atom set.

5. The compressed sensing channel estimation method based on PN correlation threshold pathfinding according to claim 4, characterized in that, If the atom index intersects with the prior atom set, the iteration parameters are updated to obtain the current iteration parameters, including: If the atomic index intersects with the prior atomic set, then the atomic index that intersects with the prior atomic set is added to the current index set and the current optimal atomic set, and the current index set and the current optimal atomic set are used as the current iteration parameters.

6. The compressed sensing channel estimation method based on PN correlation threshold pathfinding according to claim 4, characterized in that, The step of obtaining the channel estimation result based on the judgment result and the current iteration parameters includes: When the current iteration number in the current iteration parameter is less than the iteration threshold, the current iteration parameter is used as the iteration parameter in S202; Repeat steps S202-S205 until the current iteration number in the current iteration parameter is greater than the iteration threshold; Using the current iteration parameter corresponding to the iteration threshold, the channel response coefficient is calculated to obtain the channel estimation result.

7. A compressed sensing channel estimation device based on PN correlation threshold pathfinding, characterized in that, include: Acquisition unit, calculation unit, selection unit, and reconstruction unit; The acquisition unit is used to: acquire the transmission signal emitted by the transmitting station and the PN sequence generated when the transmission signal is emitted, to obtain the original reference signal and the PN sequence; The calculation unit is used to: perform correlation matching processing on the original reference signal and the PN sequence to obtain multiple matching values; The selection unit is used to: select atoms that meet the conditions from the perception matrix according to the multiple matching values, and update the initial prior atom set according to the atoms that meet the conditions to obtain the prior atom set; the perception matrix is ​​constructed based on the shifting process of the PN sequence; The computing unit is also used to: calculate the channel response coefficients based on the prior atom set and the OMP algorithm to obtain the channel estimation result; The reconstruction unit is used to: generate a multipath filter based on the channel estimation result, and perform signal reconstruction processing on the original reference signal under the action of the multipath filter to obtain a reference signal without clutter; The calculation unit performs correlation matching processing on the original reference signal and the PN sequence to obtain multiple matching values, including: Based on the original reference signal and the PN sequence, the correlation is calculated using the following formula to obtain the multiple matching values: ； in, Indicates the matching value. Indicates the channel response length. Represents a PN sequence. Indicates the first Each channel response length, The first part represents the original reference signal. Each sample value, The number of transmitted signals Each sample value, The first digit represents Gaussian white noise. Each sample value, Indicates the first Each sample value; The computing unit calculates the channel response coefficients based on the prior atom set and the OMP algorithm to obtain the channel estimation results, including: S201. Initialize iteration parameters; S202. Calculate the correlation between the residual in the iteration parameters and the perception matrix to obtain the correlation value; S203. Obtain the atom index corresponding to the relevant value from the perception matrix. and the columns corresponding to the perception matrix ; S204, if the atomic index If there is an intersection with the prior atom set, the iteration parameters are updated to obtain the current iteration parameters; S205. Determine whether the current iteration parameter meets the preset threshold, and obtain the determination result; S206. Based on the judgment result and the current iteration parameters, obtain the channel estimation result.

8. A compressed sensing channel estimation device based on PN correlation threshold pathfinding, characterized in that, include: The device includes a processor, a storage medium, and a bus. The storage medium stores machine-readable instructions executable by the processor. When the compressed sensing channel estimation device based on PN correlation threshold pathfinding is running, the processor communicates with the storage medium via the bus, and the processor executes the machine-readable instructions to perform the steps of the compressed sensing channel estimation method based on PN correlation threshold pathfinding as described in any one of claims 1-6.

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