A method and device for anti-multipath interference reception for underwater acoustic detection and communication integration

Abstract

The application discloses a kind of anti-multipath interference receiving methods and devices for underwater acoustic detection communication integration, the method receives generalized sinusoidal frequency modulation detection communication integrated signal transmitted by underwater acoustic channel, and carries out baseband processing;Channel estimation is carried out based on the training sequence of superimposed generalized sinusoidal frequency modulation phase factor, and the amplitude and time delay parameter of underwater acoustic channel sparse multipath component are obtained;Carrier phase residual is determined according to channel impulse response and generalized sinusoidal frequency modulation phase function;Residual interference component is suppressed by soft continuous interference cancellation algorithm, and the demodulated integrated receiving signal is phase compensated in the iteration process, and interference component is reconstructed and eliminated by combining the decoding result of last iteration and channel impulse response, and the integrated receiving signal is updated.The method can reduce the influence of generalized sinusoidal frequency modulation carrier phase residual interference on information decoding under multipath channel, and improve the receiving reliability of underwater acoustic detection communication integrated system.

Description

Technical Field

[0001] This invention relates to a multipath interference-resistant receiving method and device for integrated underwater acoustic detection and communication, belonging to the field of underwater acoustic detection and communication technology. Background Technology

[0002] Underwater acoustic communication and detection technologies, as key to the development of underwater acoustic information technology, cover various core application areas of underwater information interaction. With the development of ocean exploration, the required data volume is increasingly enormous, placing demands on underwater / surface platforms to simultaneously carry more detection and communication equipment. Facing the stringent requirements of gaining the initiative in information warfare, these platforms need to be equipped with a large number of sonar systems of various types, including communication and detection. The increase in the number of devices significantly exacerbates the challenges posed by limited payload space and energy supply. Furthermore, the separate design of different sonar devices is prone to significant mutual interference. Simultaneous operation of all devices results in high total power consumption, reducing the platform's stealth in underwater offensive and defensive scenarios and causing more severe platform noise interference. In addition, competition for time and frequency resources among various devices further reduces the utilization rate of scarce underwater resources, affecting the real-time performance and robustness of information acquisition. To resolve these contradictions, developing integrated detection and communication technology can achieve the organic integration of underwater acoustic detection and communication, effectively enhancing the platform's information perception and collaborative operation capabilities.

[0003] GSFM (Generalized Sinusoidal Frequency Modulated) signals can be adjusted by changing parameters. and The GSFM signal generates numerous waveforms occupying the same frequency band, and these waveforms satisfy an approximately orthogonal relationship, thus exhibiting good channel multiplexing capabilities. Furthermore, the ambiguity function of the GSFM signal is approximately "tack-shaped," providing good time delay and Doppler resolution. Due to its excellent designability and detection / communication performance, the GSFM signal is considered one of the candidate waveforms for the development of integrated underwater detection and communication technology. By modulating the intra-pulse phase of the GSFM signal, an integrated GC signal with a higher communication rate can be obtained. However, traditional Turbo-structure iterative receivers, in underwater acoustic multipath channel processing scenarios, fail to achieve optimal decoding under this structure because they do not consider the residual phase influence of the GSFM carrier under multipath interference. Therefore, it is necessary to design an anti-multipath interference receiver for integrated underwater acoustic detection and communication to achieve accurate decoding of the integrated signal. Summary of the Invention

[0004] Purpose of the invention: The purpose of this invention is to provide a method and apparatus for resisting multipath interference in integrated underwater acoustic detection and communication, which solves the problem of carrier phase residue caused by multipath channel interference in GSFM carriers by continuous interference reconstruction and elimination.

[0005] To achieve the above-mentioned objectives, the technical solution of the present invention is as follows:

[0006] Firstly, a multipath interference-resistant receiving method for integrated underwater acoustic detection and communication is provided, including:

[0007] The integrated underwater acoustic detection and communication signal is received after propagation through an underwater acoustic multipath channel and processed into baseband to obtain a baseband integrated received signal; wherein, the integrated underwater acoustic detection and communication signal is a signal formed by embedding communication information into a generalized sinusoidal frequency modulated (GSFM) signal pulse after phase modulation;

[0008] Based on the training sequence portion of the baseband integrated received signal, channel estimation is performed on the underwater acoustic multipath channel to obtain the channel impulse response amplitude and path delay corresponding to multiple multipath components, and the main path and multiple interference paths other than the main path are determined from the multiple multipath components.

[0009] Based on the path delay and phase function of the GSFM carrier signal corresponding to each interference path, determine the residual GSFM carrier phase for each interference path.

[0010] During the current receiver iteration process, continuous interference cancellation is performed on each interference path sequentially according to a preset path order. Specifically, for the current interference path to be cancelled, phase compensation is performed on the current received signal based on the GSFM carrier phase residual corresponding to the interference path. The multipath interference vector corresponding to the interference path is reconstructed based on the channel impulse response amplitude corresponding to the interference path and the decoding result obtained from the previous receiver iteration process. Based on the phase-compensated current received signal and the multipath interference vector, the multipath interference introduced by the interference path is eliminated from the current received signal to obtain an updated current received signal. The updated current received signal is then used for continuous interference cancellation of the next interference path until all interference paths are eliminated, resulting in the interference-cancelled received signal corresponding to the current receiver iteration process.

[0011] After interference cancellation, the received signal is equalized and decoded to obtain the decoding result and decoding soft information of the current receiver iteration process;

[0012] If the preset iteration termination condition is not met, the decoding result of the current receiver iteration process is used for the multipath interference vector reconstruction in the next receiver iteration process, and the decoding soft information of the current receiver iteration process is used for the equalization processing in the next receiver iteration process; if the preset iteration termination condition is met, the decoding result of the current receiver iteration process is output.

[0013] Furthermore, the baseband integrated received signal includes a training sequence part and an information sequence part. The training sequence part is formed by modulating a training sequence known in advance at the receiver with a GSFM carrier signal. The information sequence part is formed by embedding communication data into a GSFM carrier signal pulse after channel coding, interleaving processing and phase shift keying mapping.

[0014] Furthermore, channel estimation for underwater acoustic multipath channels includes:

[0015] An observation matrix is ​​constructed based on a pre-known training sequence to characterize the delay of different paths;

[0016] The training sequence portion of the baseband integrated received signal is sparsely matched with the observation matrix to determine the location of the multipath component in the underwater acoustic multipath channel.

[0017] The path delay corresponding to each multipath component is obtained based on the location of the multipath component, and the channel impulse response amplitude corresponding to each multipath component is estimated. The multipath component with the largest channel impulse response amplitude is determined as the main path, and the multipath components other than the main path are determined as interference paths.

[0018] Furthermore, the GSFM carrier phase residuals corresponding to each interference path are determined as follows:

[0019] The path delay corresponding to each interference path is input into the GSFM phase estimator, which then calculates the carrier phase deviation caused by the path delay for each interference path based on the phase function of the GSFM carrier signal.

[0020]

[0021] in, This represents the GSFM carrier phase residual value corresponding to the i-th interference path. The modulation index, , For integrated signal bandwidth, For frequency modulation terms, The dimensionless parameter controlling the shape of the instantaneous frequency function of the GSFM waveform, where t represents time t. Let be the path delay corresponding to the i-th interference path;

[0022] The carrier phase deviation is used as the GSFM carrier phase residual of the corresponding interference path.

[0023] Furthermore, the multipath interference introduced by the interference path to be eliminated from the currently received signal includes:

[0024] Based on the channel impulse response amplitude corresponding to the i-th interference path to be eliminated. The decoding result obtained from the previous receiver iteration process Perform convolution processing to obtain the multipath interference vector corresponding to the i-th interference path. ;

[0025] Based on the conjugate value of the GSFM carrier phase residual corresponding to the i-th interference path, the current received signal Perform phase compensation ; Indicates conjugate processing;

[0026] Based on the phase-compensated current received signal and the multipath interference vector, construct the interference cancellation amount corresponding to the i-th interference path. Subtract the interference cancellation amount from the current received signal to obtain the updated current received signal, as shown in the following formula:

[0027] .

[0028] Furthermore, the received signal after interference cancellation undergoes equalization and decoding processing, including:

[0029] After interference cancellation, the received signal is input into the decision feedback equalizer, and during non-first receiver iterations, the decoding soft information obtained from the previous receiver iteration is used as the prior information of the decision feedback equalizer.

[0030] The log-likelihood ratio of each symbol to be decoded in the received signal after interference cancellation is calculated by the decision feedback equalizer, and the log-likelihood ratio is output as the external information of the equalization.

[0031] The equalization external information is deinterleaved, and the deinterleaved equalization external information is input into the channel decoder for channel decoding to obtain the decoding soft information;

[0032] The decoding soft information is judged to obtain the decoding result of the current receiver iteration process.

[0033] In a second aspect, a receiver device includes:

[0034] The baseband processing module is used to receive the integrated underwater acoustic detection and communication signal after propagation through the underwater acoustic multipath channel, and perform baseband processing to obtain the integrated baseband received signal; wherein, the integrated underwater acoustic detection and communication signal is a signal formed by embedding the communication information into a generalized sinusoidal frequency modulated (GSFM) signal pulse after phase modulation;

[0035] The channel estimation module is used to perform channel estimation on the underwater acoustic multipath channel based on the training sequence part of the baseband integrated received signal, to obtain the channel impulse response amplitude and path delay corresponding to multiple multipath components, and to determine the main path and multiple interference paths other than the main path from the multiple multipath components.

[0036] The carrier phase residual determination module is used to determine the GSFM carrier phase residual amount corresponding to each interference path based on the path delay and the phase function of the GSFM carrier signal.

[0037] The interference cancellation module is used to perform continuous interference cancellation on each interference path sequentially according to a preset path order during the current receiver iteration process. Specifically, for the current interference path to be cancelled, the phase compensation of the current received signal is performed based on the GSFM carrier phase residual corresponding to the interference path, and the multipath interference vector corresponding to the interference path is reconstructed based on the channel impulse response amplitude corresponding to the interference path and the decoding result obtained from the previous receiver iteration process. Based on the phase-compensated current received signal and the multipath interference vector, the multipath interference introduced by the interference path is eliminated from the current received signal to obtain an updated current received signal. The updated current received signal is then used for continuous interference cancellation on the next interference path until all interference paths are eliminated, resulting in the interference-cancelled received signal corresponding to the current receiver iteration process.

[0038] The equalization and decoding module is used to equalize and decode the received signal after interference cancellation to obtain the decoding result and decoding soft information of the current receiver iteration process.

[0039] The iteration control module is used to use the decoding result of the current receiver iteration process for multipath interference vector reconstruction in the next receiver iteration process and to use the decoding soft information of the current receiver iteration process for equalization processing in the next receiver iteration process when the preset iteration termination condition is not met; when the preset iteration termination condition is met, the module outputs the decoding result of the current receiver iteration process.

[0040] The present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, it implements the above-described anti-multipath interference receiving method for integrated underwater acoustic detection and communication.

[0041] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-described anti-multipath interference receiving method for integrated underwater acoustic detection and communication.

[0042] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described anti-multipath interference receiving method for integrated underwater acoustic detection and communication.

[0043] Beneficial effects:

[0044] (1) This invention addresses the integrated underwater acoustic detection and communication signal formed by embedding communication phase information within the GSFM carrier signal pulse, taking into account the residual GSFM carrier phase caused by different multipath components during underwater acoustic multipath propagation. Compared to the receiving processing method that treats multipath propagation merely as ordinary inter-symbol interference, this invention combines the path delay of the multipath components with the phase function of the GSFM carrier signal to determine the residual GSFM carrier phase corresponding to each multipath component. This enables the receiver to perform interference modeling based on the carrier phase characteristics of the integrated signal itself, thereby improving the accuracy of multipath interference characterization.

[0045] (2) In the multipath interference cancellation process, this invention does not simply perform conventional reconstruction of multipath interference based on the channel impulse response. Instead, it first uses the GSFM carrier phase residual corresponding to the multipath component to be cancelled to perform phase compensation on the demodulated integrated received signal. Then, it combines the channel impulse response corresponding to the multipath component to be cancelled and the decoding result obtained from the previous iteration to generate an interference vector, and updates the current received signal accordingly. This reduces the impact of the GSFM carrier phase residual on the communication phase decision and improves the matching degree between the interference cancellation result and the actual received signal. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments are briefly introduced below. The drawings described below are only some embodiments of the present invention, wherein:

[0047] Figure 1 This is an algorithm flowchart of the method of the present invention;

[0048] Figure 2 Comparison of autocorrelation functions between integrated signal and GSFM signal under the same parameters;

[0049] Figure 3 The impulse response of the sparse underwater acoustic channel used in the experimental simulation;

[0050] Figure 4 , Figure 5 and Figure 6 This is a performance comparison of the traditional direct decoding method and the interference cancellation-based decoding method mentioned in this invention, under different bandwidth ratios, with varying iterations and signal-to-noise ratios.

[0051] Figure 7 The signal frame synchronization results clearly show two non-direct paths.

[0052] Figure 8This paper compares the performance of two processing methods—the traditional direct decoding method and the interference cancellation-based decoding method mentioned in this invention—with the number of iterations and the change in signal-to-noise ratio, after reducing the signal-to-noise ratio (SNR) of the data collected in the Songhua River ice-covered experiment and under different bandwidth ratios. Detailed Implementation

[0053] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention. Those skilled in the art can make equivalent substitutions or adjustments to the specific processing algorithms or parameter settings therein.

[0054] This invention addresses the issue of GSFM intra-pulse phase modulation integrated signals, which, after underwater acoustic multipath propagation, not only suffer from ordinary inter-symbol interference but also from GSFM carrier phase remnants due to different path delays. A multipath interference-resistant reception method is proposed. The receiver uses the path delay estimated by sparse channels to calculate the GSFM carrier phase remnant for each path, and incorporates this phase remnant into path-by-path interference reconstruction and continuous cancellation. The interference reconstruction is then updated through decoding feedback, thus forming a phase-aware iterative reception processing method for GSFM integrated signals.

[0055] The transmitting end processing flow is as follows:

[0056] (1) Generalized Sinusoidal Frequency Modulation (GSFM) Carrier Signal Generation: The GSFM signal generator generates a carrier signal based on the allocated bandwidth. Determine signal parameters based on the actual channel environment. and This generates a GSFM carrier signal with strong channel adaptability.

[0057] For the generation of a generalized sinusoidal frequency modulated (GSFM) signal, the expression for the passband GSFM signal pulse is:

[0058]

[0059] in Represents the center frequency of the GSFM signal. The phase of the GSFM signal over time Change relationship, and Both are dimensionless modulation parameters of GSFM signals For GSFM signal bandwidth, The GSFM signal pulse period;

[0060] (2) Modulation of the integrated signal: After channel coding and interleaving, the information sequence is mapped by QPSK into a complex baseband phase signal with a bandwidth of [missing information]. The complex baseband phase signal is multiplied with the carrier signal, and the phase information is embedded into the GSFM carrier signal pulse, modulating it into an integrated signal.

[0061] For the generation of the integrated signal, the transmission sequence consists of two parts: a training sequence and an information sequence. The transmission sequence is then subjected to convolutional channel coding and interleaving. The processed data is then mapped into a complex baseband phase signal using QPSK.

[0062]

[0063] in, Indicates the number of bits transmitted. For the channel coding and interleaving of the first One information bit, The PSK symbol pulse period and PSK bandwidth relationship are as follows: , This represents a rectangular window function. The integrated GC signal expression obtained by embedding the PSK signal into the GSFM signal pulse is as follows:

[0064]

[0065] in, This represents the phase jump of the integrated waveform. Therefore, the bandwidth of the integrated signal GC can be expressed as:

[0066] in, This is the bandwidth ratio coefficient of the integrated waveform, which controls the proportion of the total bandwidth occupied by the PSK signal and the GSFM signal in the integrated signal.

[0067] At the receiver, based on the training sequence, the acquired passband integrated signal is initially demodulated to baseband. The training sequence portion of the baseband integrated signal is extracted, and a Toeplitz observation matrix is ​​constructed using the training sequence modulated with the baseband GSFM signal. The channel impulse response is then estimated using the Orthogonal Matching Pursuit (OMP) algorithm. Obtain the corresponding delay for each path. It can calculate the residual carrier phase of each path. Therefore, the true phase under carrier phase interference is determined by jump to By combining the known iterative decoding results with the channel estimation results, the multipath interference of each channel path on the integrated signal is reconstructed, and the influence of carrier phase residue is continuously eliminated. The demodulation results of the received signal are updated and input into the decision feedback equalizer. The log-likelihood ratio of the received signal is calculated as external information flow. The current decoding result and decoding soft information are obtained in the channel decoder as prior information for the next iteration. The decoding result is used to update the interference reconstruction for the next iteration to obtain a more accurate demodulation result of the received signal, thus forming a closed loop of the iterative decoding structure and gradually improving the decoding accuracy of the iterative receiver.

[0068] Reference Figure 1 The specific processing flow at the receiving end is as follows:

[0069] (1) Channel estimation based on training sequence: The receiver uses the training sequence modulated by the baseband GSFM signal as prior information to construct the Toeplitz observation matrix of the orthogonal matching pursuit algorithm. Each column of the matrix corresponds to the single sampling point delay of the training sequence vector. Combined with the integrated signal after baseband processing, the accurate estimation of the multipath structure of the underwater acoustic channel environment is achieved by judging the column correlation between the received signal and the observation matrix. The termination condition of the OMP algorithm is that it is lower than the preset channel impulse response threshold.

[0070] The multipath component with the largest channel impulse response amplitude is determined as the main path, and the multipath components other than the main path are the interference paths.

[0071] (2) Carrier phase residual interference calculation: Based on the channel estimation results, the delay of each path is obtained and input into the generalized sinusoidal frequency modulated signal (GSFM) phase estimator. The output is the phase residual of the GSFM carrier signal in each interference path.

[0072] The time delays corresponding to each interference path obtained from channel estimation The input phase calculation module calculates the carrier phase deviation caused by each path. The residual carrier phase deviation caused by each path can be expressed as:

[0073]

[0074] in, The modulation index, , For integrated signal bandwidth, For frequency modulation terms, The dimensionless parameter controlling the shape of the instantaneous frequency function of the GSFM waveform. t represents time t.

[0075] (3) Continuous multipath interference reconstruction and elimination: Based on the channel impulse response amplitude obtained by channel estimation and the carrier phase residual value output by the phase estimator, combined with the prior information obtained by the previous decoding, the interference of each path is reconstructed in sequence, and the interference of other paths besides the main path is continuously eliminated in the received signal.

[0076] The first The residual phase interference caused by the stripe is compensated to the demodulated integrated signal. The received signal after compensating for the residual phase of the carrier is obtained:

[0077]

[0078] in, This indicates that the residual phase deviation of the carrier is treated as a conjugate.

[0079] No. The interference vector can be reconstructed as:

[0080]

[0081] in, It is the decoding result from the previous decoder, serving as prior information for this interference reconstruction. Representing the The channel impulse response of the stripe path. Therefore, in eliminating the first... After multipath interference in the stripe path, the received signal is updated as follows:

[0082]

[0083] (4) Decoding result and decoding soft information output: Solve the log-likelihood ratio of the equalized signal, and feed the external information into the deinterleaver, decoder and decision unit in sequence to obtain the decoding result and decoding soft information. The decoding soft information is used as prior information to participate in the next iteration. The decoding result is used to reconstruct multipath interference by combining the channel estimation result.

[0084] The received signal has been updated after continuous multipath interference cancellation. After decision feedback equalization, the log-likelihood ratio is output as extrinsic information. After deinterleaving, it is sequentially fed into the channel decoder and the decision unit to output the decoding result. The former is used for interference reconstruction in the next iteration, while the latter is used as prior information input into the DFE equalizer in the next iteration.

[0085] (5) Determine whether the number of iterations has reached the preset maximum number of iterations. If it has, output the decoding result and end the decoding; otherwise, return to step (3) to continue the iteration.

[0086] This invention utilizes an intra-pulse phase modulation method to construct an integrated signal, and the waveform of the carrier GSFM signal can be adjusted by parameters. and and bandwidth usage This technology achieves flexible adaptation to different application scenarios, significantly improving data transmission rates without compromising carrier detection performance. Furthermore, it proposes a targeted solution to the phase residual interference problem neglected in traditional iterative receiver decoding, reconstructing and eliminating the multipath interference caused by multipath channels. This achieves the higher-level performance of a classic turbo-structure iterative receiver decoder, enhancing the system's anti-interference capability and communication reliability.

[0087] in accordance with Figure 1 The process underwent scenario simulation under multipath interference. The system parameters were: the total bandwidth of the integrated signal was 2.2 kHz, where the bandwidth allocation ratio was determined by parameters. It has been decided that this experiment simulates... Simulation results were obtained using three classic bandwidth scaling factors, a carrier center frequency of 4 kHz, a sampling rate of 48 kHz, an information sequence length of 8000 bits, and a convolutional code rate of 1 / 2, through a total of 50 Monte Carlo simulations.

[0088] Figure 2 The autocorrelation functions of the integrated signal and the GSFM signal under the same parameters are compared. It can be seen that the embedding of communication information not only does not affect the detection performance of the GSFM signal, but also suppresses the autocorrelation sidelobes of the GSFM signal due to the randomization characteristics of the communication information.

[0089] Figure 3 The sparse underwater acoustic channel impulse response used in the experimental simulation has a total of 5 paths.

[0090] Figure 4 , Figure 5 , Figure 6 The performance of two processing methods, direct decoding and decoding after interference cancellation, was compared under different bandwidth ratios, with varying iterations and signal-to-noise ratios. Figure 4 show, At that time, the method of the present invention achieved a significant performance advantage of 8dB. Figure 5 show, At that time, the method of the present invention achieved a significant performance advantage of 8dB. Figure 6 show, At that time, the method of this invention achieved a significant performance advantage of 4dB. Moreover, this performance advantage was evident in the second iteration. Horizontal comparison results show that... This set of bandwidth allocation coefficients performs better than other coefficients.

[0091] The advantages of this invention will be further explained below in conjunction with the results of experimental data processing.

[0092] Experimental data verification:

[0093] In February 2026, an integrated signal under-ice experiment was conducted in the Songhua River basin of Harbin City, Heilongjiang Province. The average water depth of the experimental area was approximately 8 meters. The sound source was placed 4.3 meters below the ice surface, and the hydrophone was placed 3 meters below the ice surface, with a distance of approximately 500 meters between them. Due to the limitation of the sound source's transmission frequency of 2-5 kHz, the carrier center frequency was adjusted to 3 kHz, while the remaining parameters remained consistent with the simulation.

[0094] The frame synchronization results of the received signal are as follows Figure 7 In the synchronization results, two distinct non-direct paths are clearly visible in our experimental environment. The results of the received signal data processing are shown in Table 1. EVM is defined to compare constellation point recovery capabilities under the same bit error rate.

[0095]

[0096] in, For real zodiac points, The table shows the constellation points recovered from the received signal. As can be seen from the table, due to the high signal-to-noise ratio limitation of the experimental environment, both methods can achieve zero bit error rate due to iterative gain, and the performance difference between the two methods cannot be clearly compared. For a clear comparison, noise data before and after the signal frame was artificially collected and superimposed on the received signal to reduce the signal-to-noise ratio of the received signal and simulate a longer communication distance. The final performance comparison results of the proposed method and the traditional method under the two bandwidth ratio coefficients are as follows: Figure 8 As shown in Table 1. Figure 8 In the figure, (a) represents the bandwidth scaling factor. In comparison, (b) is the bandwidth ratio factor. The comparison.

[0097] Table 1. Results of data processing for the Songhua River under-ice communication experiment.

[0098]

[0099] The final results show that, compared to traditional direct decoding methods, the method of this invention achieves superior decoding performance in the second iteration. While traditional methods can approximate the optimal decoding result through multiple iterations under certain signal-to-noise ratio conditions, this gain is merely due to iteration within the Turbo decoding architecture and does not truly consider the characteristics of the signal itself in the actual underwater acoustic environment or the inherent characteristics of the underwater acoustic channel. The method of this invention takes into account both the signal's inherent characteristics and the underwater acoustic channel environment, eliminating the influence of carrier phase on the signal itself under the channel environment. This significantly improves the convergence speed of classical methods, saves computational resources, and effectively enhances the system's robustness and anti-interference capabilities.

[0100] The above results demonstrate that the method and system proposed in this invention exhibit superior decoding performance and higher convergence speed compared to classical methods in underwater acoustic channel multipath interference environments, further proving their effectiveness and engineering application value in integrated underwater acoustic detection and communication systems.

[0101] The present invention also provides a receiver device, comprising:

[0102] The baseband processing module is used to receive the integrated underwater acoustic detection and communication signal after propagation through the underwater acoustic multipath channel, and perform baseband processing to obtain the integrated baseband received signal; wherein, the integrated underwater acoustic detection and communication signal is a signal formed by embedding the communication information into a generalized sinusoidal frequency modulated (GSFM) signal pulse after phase modulation;

[0103] The channel estimation module is used to perform channel estimation on the underwater acoustic multipath channel based on the training sequence part of the baseband integrated received signal, to obtain the channel impulse response amplitude and path delay corresponding to multiple multipath components, and to determine the main path and multiple interference paths other than the main path from the multiple multipath components.

[0104] The carrier phase residual determination module is used to determine the GSFM carrier phase residual amount corresponding to each interference path based on the path delay and the phase function of the GSFM carrier signal.

[0105] The interference cancellation module is used to perform continuous interference cancellation on each interference path sequentially according to a preset path order during the current receiver iteration process. Specifically, for the current interference path to be cancelled, the phase compensation of the current received signal is performed based on the GSFM carrier phase residual corresponding to the interference path, and the multipath interference vector corresponding to the interference path is reconstructed based on the channel impulse response amplitude corresponding to the interference path and the decoding result obtained from the previous receiver iteration process. Based on the phase-compensated current received signal and the multipath interference vector, the multipath interference introduced by the interference path is eliminated from the current received signal to obtain an updated current received signal. The updated current received signal is then used for continuous interference cancellation on the next interference path until all interference paths are eliminated, resulting in the interference-cancelled received signal corresponding to the current receiver iteration process.

[0106] The equalization and decoding module is used to equalize and decode the received signal after interference cancellation to obtain the decoding result and decoding soft information of the current receiver iteration process.

[0107] The iteration control module is used to use the decoding result of the current receiver iteration process for multipath interference vector reconstruction in the next receiver iteration process and to use the decoding soft information of the current receiver iteration process for equalization processing in the next receiver iteration process when the preset iteration termination condition is not met; when the preset iteration termination condition is met, the module outputs the decoding result of the current receiver iteration process.

[0108] The present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, it implements the above-described anti-multipath interference receiving method for integrated underwater acoustic detection and communication.

[0109] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-described anti-multipath interference receiving method for integrated underwater acoustic detection and communication.

[0110] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described anti-multipath interference receiving method for integrated underwater acoustic detection and communication.

[0111] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A multipath interference-resistant receiving method for integrated underwater acoustic detection and communication, characterized in that, Includes the following steps: The integrated underwater acoustic detection and communication signal is received after propagation through an underwater acoustic multipath channel and processed into baseband to obtain a baseband integrated received signal; wherein, the integrated underwater acoustic detection and communication signal is a signal formed by embedding communication information into a generalized sinusoidal frequency modulated (GSFM) signal pulse after phase modulation; Based on the training sequence portion of the baseband integrated received signal, channel estimation is performed on the underwater acoustic multipath channel to obtain the channel impulse response amplitude and path delay corresponding to multiple multipath components, and the main path and multiple interference paths other than the main path are determined from the multiple multipath components. Based on the path delay and phase function of the GSFM carrier signal corresponding to each interference path, determine the residual GSFM carrier phase for each interference path. During the current receiver iteration process, continuous interference cancellation is performed on each interference path sequentially according to a preset path order. Specifically, for the current interference path to be cancelled, phase compensation is performed on the current received signal based on the GSFM carrier phase residual corresponding to the interference path. The multipath interference vector corresponding to the interference path is reconstructed based on the channel impulse response amplitude corresponding to the interference path and the decoding result obtained from the previous receiver iteration process. Based on the phase-compensated current received signal and the multipath interference vector, the multipath interference introduced by the interference path is eliminated from the current received signal to obtain an updated current received signal. The updated current received signal is then used for continuous interference cancellation of the next interference path until all interference paths are eliminated, resulting in the interference-cancelled received signal corresponding to the current receiver iteration process. After interference cancellation, the received signal is equalized and decoded to obtain the decoding result and decoding soft information of the current receiver iteration process; If the preset iteration termination condition is not met, the decoding result of the current receiver iteration process is used for the multipath interference vector reconstruction in the next receiver iteration process, and the decoding soft information of the current receiver iteration process is used for the equalization processing in the next receiver iteration process; if the preset iteration termination condition is met, the decoding result of the current receiver iteration process is output.

2. The method according to claim 1, characterized in that, The baseband integrated receiving signal includes a training sequence part and an information sequence part. The training sequence part is formed by modulating a training sequence known in advance at the receiver with a GSFM carrier signal. The information sequence part is formed by embedding communication data into a GSFM carrier signal pulse after channel coding, interleaving, and phase shift keying mapping.

3. The method according to claim 1, characterized in that, Channel estimation for underwater acoustic multipath channels includes: An observation matrix is ​​constructed based on a pre-known training sequence to characterize the delay of different paths; The training sequence portion of the baseband integrated received signal is sparsely matched with the observation matrix to determine the location of the multipath component in the underwater acoustic multipath channel. The path delay corresponding to each multipath component is obtained based on the location of the multipath component, and the channel impulse response amplitude corresponding to each multipath component is estimated. The multipath component with the largest channel impulse response amplitude is determined as the main path, and the multipath components other than the main path are determined as interference paths.

4. The method according to claim 1, characterized in that, The determination of the GSFM carrier phase residual for each interference path includes: The path delay corresponding to each interference path is input into the GSFM phase estimator, which then calculates the carrier phase deviation caused by the path delay for each interference path based on the phase function of the GSFM carrier signal. in, This represents the GSFM carrier phase residual value corresponding to the i-th interference path. The modulation index, , For integrated signal bandwidth, For frequency modulation terms, The dimensionless parameter controlling the shape of the instantaneous frequency function of the GSFM waveform, where t represents time t. Let be the path delay corresponding to the i-th interference path; The carrier phase deviation is used as the GSFM carrier phase residual of the corresponding interference path.

5. The method according to claim 4, characterized in that, Eliminate multipath interference introduced by the current interference path to be eliminated from the currently received signal, including: Based on the channel impulse response amplitude corresponding to the i-th interference path to be eliminated. The decoding result obtained from the previous receiver iteration process Perform convolution processing to obtain the multipath interference vector corresponding to the i-th interference path. ; Based on the conjugate value of the GSFM carrier phase residual corresponding to the i-th interference path, the current received signal Perform phase compensation ; Indicates conjugate processing; Based on the phase-compensated current received signal and the multipath interference vector, construct the interference cancellation amount corresponding to the i-th interference path. Subtract the interference cancellation amount from the current received signal to obtain the updated current received signal, as shown in the following formula: 。 6. The method according to claim 1, characterized in that, After interference cancellation, the received signal undergoes equalization and decoding processing, including: After interference cancellation, the received signal is input into the decision feedback equalizer, and during non-first receiver iterations, the decoding soft information obtained from the previous receiver iteration is used as the prior information of the decision feedback equalizer. The log-likelihood ratio of each symbol to be decoded in the received signal after interference cancellation is calculated by the decision feedback equalizer, and the log-likelihood ratio is output as the external information of the equalization. The equalization external information is deinterleaved, and the deinterleaved equalization external information is input into the channel decoder for channel decoding to obtain the decoding soft information; The decoding soft information is judged to obtain the decoding result of the current receiver iteration process.

7. A receiver device, characterized in that, include: The baseband processing module is used to receive the integrated underwater acoustic detection and communication signal after propagation through the underwater acoustic multipath channel, and perform baseband processing to obtain the integrated baseband received signal; wherein, the integrated underwater acoustic detection and communication signal is a signal formed by embedding the communication information into a generalized sinusoidal frequency modulated (GSFM) signal pulse after phase modulation; The channel estimation module is used to perform channel estimation on the underwater acoustic multipath channel based on the training sequence part of the baseband integrated received signal, to obtain the channel impulse response amplitude and path delay corresponding to multiple multipath components, and to determine the main path and multiple interference paths other than the main path from the multiple multipath components. The carrier phase residual determination module is used to determine the GSFM carrier phase residual amount corresponding to each interference path based on the path delay and the phase function of the GSFM carrier signal. The interference cancellation module is used to perform continuous interference cancellation on each interference path sequentially according to a preset path order during the current receiver iteration process. Specifically, for the current interference path to be cancelled, the phase compensation of the current received signal is performed based on the GSFM carrier phase residual corresponding to the interference path, and the multipath interference vector corresponding to the interference path is reconstructed based on the channel impulse response amplitude corresponding to the interference path and the decoding result obtained from the previous receiver iteration process. Based on the phase-compensated current received signal and the multipath interference vector, the multipath interference introduced by the interference path is eliminated from the current received signal to obtain an updated current received signal. The updated current received signal is then used for continuous interference cancellation on the next interference path until all interference paths are eliminated, resulting in the interference-cancelled received signal corresponding to the current receiver iteration process. The equalization and decoding module is used to equalize and decode the received signal after interference cancellation to obtain the decoding result and decoding soft information of the current receiver iteration process. The iteration control module is used to use the decoding result of the current receiver iteration process for multipath interference vector reconstruction in the next receiver iteration process and to use the decoding soft information of the current receiver iteration process for equalization processing in the next receiver iteration process when the preset iteration termination condition is not met; when the preset iteration termination condition is met, the module outputs the decoding result of the current receiver iteration process.

8. An electronic device, characterized in that, It includes a processor and a memory, the memory storing a computer program, which, when executed by the processor, implements the anti-multipath interference receiving method for integrated underwater acoustic detection and communication as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The device contains a computer program that, when executed by a processor, implements the anti-multipath interference receiving method for integrated underwater acoustic detection and communication as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the anti-multipath interference receiving method for integrated underwater acoustic detection and communication as described in any one of claims 1 to 6.

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