Dual-channel positive and negative frequency modulation signal processing method, device, equipment, medium and product

Abstract

The application discloses a double-channel positive and negative frequency modulation signal processing method, device, equipment, medium and product, relates to the underwater detection field, and the method comprises the following steps: a first channel and a second channel in a double-channel transducer respectively emit a positive frequency modulation signal s1 and a negative frequency modulation signal s2 to a target; after reflection of the target, a signal received by the first channel is y1, and a signal received by the second channel is y2; the received signals y1 and y2 are subjected to downmixing processing; the signal subjected to the downmixing processing is subjected to low-pass filtering; the signal subjected to the low-pass filtering is subjected to down-sampling; the signal subjected to the down-sampling is subjected to pulse compression; and the signal subjected to the pulse compression is subjected to envelope calculation. The application improves the signal-to-noise ratio of a signal, and further improves the recognition accuracy of a target.

Description

Technical Field

[0001] This application relates to the field of underwater detection, and in particular to a dual-channel positive and negative frequency modulation signal processing method, apparatus, equipment, medium and product. Background Technology

[0002] In the field of underwater detection technology, with the increasing demand for assessment of underwater biological and resource locations, the application of fishing sonar is also increasing. Sonar technology is mainly classified into single-beam, split-beam, and multi-beam types based on the method of sound wave beam transmission. Single-beam sonar, as a widely used underwater detection device, includes single-beam depth sounders and mechanically rotating sonars, and is widely used in underwater robotic systems such as underwater sediment measurement and seabed obstacle avoidance due to its simple structure. However, single-beam sonar has some limitations in practical applications, such as high sidelobes and a wide main lobe leading to limited resolution, inability to automatically detect and identify small targets, and slow scanning speed affecting real-time detection.

[0003] On the other hand, while multi-channel sonar can provide more comprehensive, detailed, and higher-resolution detection data, its design and manufacturing process is more complex, requiring advanced instrument manufacturing technology and sophisticated sonar sensors, thus resulting in higher costs. Furthermore, multi-beam systems have higher demands on computing and storage devices when processing large amounts of data, which also limits their widespread use in certain application scenarios.

[0004] In light of the above background, this invention aims to address the shortcomings of existing single-beam sonar in terms of resolution, target identification, and real-time performance, while simultaneously reducing the cost and data processing requirements of multi-channel sonar systems to meet the needs of underwater detection technology development and promote the efficiency and accuracy of underwater resource assessment and biological detection. Through an innovative technical solution, this invention aims to provide an economical and efficient dual-channel positive and negative frequency modulation signal processing method to adapt to the ever-growing market demands of underwater detection. Summary of the Invention

[0005] The purpose of this application is to provide a dual-channel positive and negative frequency modulation signal processing method, apparatus, device, medium, and product, which can improve the signal-to-noise ratio of the signal and thus improve the target recognition accuracy.

[0006] To achieve the above objectives, this application provides the following solution:

[0007] In a first aspect, this application provides a dual-channel positive and negative frequency modulation signal processing method, including:

[0008] The first and second channels of the dual-channel transducer transmit a positive frequency modulation signal s1 and a negative frequency modulation signal s2 to the target, respectively.

[0009] After being reflected by the target, the signal received by the first channel is y1, and the signal received by the second channel is y2;

[0010] performing down-mixing processing on the received signals y1 and y2;

[0011] performing low-pass filtering on the signals after down-mixing processing;

[0012] performing down-sampling on the low-pass filtered signals;

[0013] performing pulse compression on the down-sampled signals;

[0014] performing envelope extraction on the pulse-compressed signals.

[0015] Optionally, the expression of the positive frequency modulation signal s1 is: s1=cos(2πf1t+πkt 2 )

[0016] The expression of the negative frequency modulation signal s2 is: s2=cos(2πf2t-πkt 2 )

[0017] wherein f1 and f2 are carrier frequencies, the bandwidth of the frequency modulation signal is f1 ~ f2, f1 < f2, k = bw / T, bw is the signal bandwidth, T is the signal pulse width, and t represents sampling time;

[0018] said down-mixing processing of the received signals y1 and y2 specifically adopts the following formula:

[0019] y DDC1 =y1·cos(2f1t)-1j·y1·sin(2f1t)

[0020] y DDC2 =y2·cos(2f1t)-1j·y2·sin(2f1t)

[0021] wherein y DDC1 represents the complex signal generated by the first channel after down-mixing, y DDC2 represents the complex signal generated by the second channel after down-mixing, f1 and f2 are carrier frequencies, and j represents the unit of imaginary part.

[0022] Optionally, said low-pass filtering of the signals after down-mixing processing specifically adopts the following formula:

[0023]

[0024]

[0025] wherein y LP1 represents the complex signal output by the first channel after passing through the low-pass filter, yLP2 This represents the complex signal output from the second channel after passing through the low-pass filter, y. DDC1 This represents the complex signal output from the first channel after passing through the downmixing module, y. DDC2 f represents the complex signal output from the second channel after passing through the downmixing module. c The filter cutoff frequency is represented by t, the sampling time is represented by t, and * represents the convolution operation.

[0026] Optionally, the downsampling of the low-pass filtered signal is specifically performed using the following formula:

[0027]

[0028] Among them, y DSR1 (t) represents the complex signal output from the first channel after downsampling, y DSR2 (t) represents the complex signal output from the second channel after downsampling, y LP1 y represents the complex signal output from the first channel after passing through the low-pass filter. LP2 This represents the complex signal output from the second channel after passing through a low-pass filter. DSR represents the downsampling rate, and t represents the sampling time.

[0029] Optionally, the pulse compression of the downsampled signal is specifically performed using the following formula:

[0030] y mf1_re =y DSR1_re *F 1_re -y DSR1_im *F 1_im

[0031] y mf1_im =y DSR1_re *F 1_im +y DSR1_im *F 1_re

[0032] y mf2_re =y DSR2_re *F 2_re -y DSR2_im *F 2_im

[0033] y mf2_im =y DSR2_re *F 2_im +y DSR2_im *F 2_re

[0034] Among them, y mf1 This represents the complex signal output from the first channel after pulse compression, y mf2 This represents the complex signal output from the second channel after pulse compression; y DSR1_rey represents the real part of the complex signal output from the first channel after downsampling. DSR2_re y represents the real part of the complex signal output from the second channel after downsampling; DSR1_im y represents the imaginary part of the complex signal output from the first channel after downsampling. DSR2_im This represents the imaginary part of the complex signal output from the second channel after downsampling.

[0035] y DSR1_im y represents the imaginary part of the complex signal output from the first channel after downsampling. DSR2_im This represents the imaginary part of the complex signal output from the second channel after downsampling.

[0036] y mf1 =y mf1_re +1j·y mf1_im

[0037] y mf2 =y mf2_re +1j·y mf2_im

[0038] y mf1_re y represents the real part of the complex signal output from the first channel after pulse compression. mf2_re This represents the real part of the complex signal output from the second channel after pulse compression.

[0039] y mf1_im y represents the imaginary part of the complex signal output from the first channel after pulse compression. mf2_im This represents the imaginary part of the complex signal output from the second channel after pulse compression.

[0040] F1 is a local complex signal pre-stored in the receiving link of the first channel, and F2 is a local signal pre-stored in the receiving link of the second channel.

[0041] F1 = F 1_re +1j·F 1_im

[0042] F2 = F 2_re +1j·F 2_im

[0043] F 1_re F is the real part of the local complex signal pre-existing in the receiving link of the first channel. 2_re F is the real part of the local complex signal pre-existing in the receiving link of the second channel. 1_im F is the imaginary part of the local complex signal pre-existing in the receiving link of the first channel. 2_im It is the imaginary part of the local complex signal pre-existing in the receiving link of the second channel.

[0044] Optionally, the envelope of the pulse-compressed signal can be obtained using the following formula:

[0045]

[0046] Where z1 represents the output signal of the first channel after envelope calculation, z2 represents the output signal of the second channel after envelope calculation, and y mf1_re y represents the real part of the complex signal output from the first channel after pulse compression. mf1_im y represents the imaginary part of the complex signal output from the first channel after pulse compression. mf2_re y represents the real part of the complex signal output from the second channel after pulse compression. mf2_im This represents the imaginary part of the complex signal output from the second channel after pulse compression.

[0047] Secondly, this application provides a dual-channel positive and negative frequency modulation signal processing device, comprising:

[0048] The signal acquisition module is used to transmit a positive frequency modulation signal s1 and a negative frequency modulation signal s2 to the target using the first and second channels of the dual-channel transducer, respectively.

[0049] After being reflected by the target, the signal acquisition module receives signal y1 through the first channel and signal y2 through the second channel.

[0050] The downmixing module is used to perform downmixing processing on the received signals y1 and y2.

[0051] The low-pass filter module is used to perform low-pass filtering on the signal after down-mixing.

[0052] The downsampling module is used to downsample the low-pass filtered signal;

[0053] The pulse compression module is used to compress the downsampled signal into pulses.

[0054] The envelope acquisition module is used to acquire the envelope of the pulse-compressed signal.

[0055] Thirdly, this application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the dual-channel positive and negative frequency modulation signal processing method described in any one of the above.

[0056] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the dual-channel positive and negative frequency modulation signal processing method described above.

[0057] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the dual-channel positive and negative frequency modulation signal processing method described above.

[0058] According to the specific embodiments provided in this application, the following technical effects are disclosed:

[0059] This application provides a dual-channel positive and negative frequency modulation signal processing method, apparatus, device, medium, and product. The first channel of the dual-channel transducer transmits a positive frequency modulated signal, and the receiving link of the first channel also stores a positive frequency modulated signal. The second channel transmits a negative frequency modulated signal, and the receiving link of the second channel also stores a negative frequency modulated signal. When the target is near the sound ray of the first channel, the signal transmitted by the first channel, after reflection, can only effectively pulse compress with the local signal of the first channel to produce a single peak value, but cannot produce a peak value with the local signal in the second channel. Therefore, only one bright spot will appear on the host computer user interface. Furthermore, due to pulse compression, the signal-to-noise ratio is high, resulting in a cleaner and more reliable signal. Consequently, when transmitted to the host computer for interface display, the influence of noise and other non-target objects is minimal, making the user interface clearer and more intuitive, thus improving the efficiency and accuracy of biological detection. Attached Figure Description

[0060] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0061] Figure 1 This is a schematic diagram of the dual-channel transducer arrangement in one embodiment of this application;

[0062] Figure 2 This is a flowchart illustrating a dual-channel positive and negative frequency modulation signal processing method according to an embodiment of this application;

[0063] Figure 3 A schematic diagram of a dual-channel positive and negative frequency modulation signal processing method provided in an embodiment of this application;

[0064] Figure 4 This application provides an embodiment of the amplitude variation with frequency in the 22.5° direction;

[0065] Figure 5 This is a schematic diagram of the result after obtaining the envelope in one embodiment of this application;

[0066] Figure 6This is a schematic diagram of the test results for testing an anechoic water tank according to one embodiment of this application;

[0067] Figure 7 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0068] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0069] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0070] Figure 1 This is a schematic diagram of the dual-channel transducer arrangement in one embodiment of this application. See also: Figure 1 Label 1 is a dual-channel transducer, 2 is the sound ray, that is, the propagation path of the emitted waveform, representing the direction of wave propagation; 3 is the main lobe of the beam, which is usually aligned with the center of the sensor array and reflects the main observation or emission direction of the system. The main lobes of the two channels are spaced 22.5° apart.

[0071] Figure 2 This is a flowchart illustrating a dual-channel positive and negative frequency modulation signal processing method according to an embodiment of this application. Figure 3 This is a schematic diagram of a dual-channel positive and negative frequency modulation signal processing method provided in an embodiment of this application, combined with... Figure 2 and Figure 3 The dual-channel positive and negative frequency modulation signal processing method in this application specifically includes the following steps:

[0072] Step 101: The first and second channels of the dual-channel transducer transmit positive frequency modulation signal s1 and negative frequency modulation signal s2 to the target, respectively.

[0073] The dual-channel transducer transmitter section includes two channels, a first channel and a second channel, which transmit different frequency modulation signals respectively. The first channel transmits a positive frequency modulation signal s1.

[0074] s1=cos(2πf1t+πkt 2 )

[0075] The second channel transmits a negative frequency modulated signal s2:

[0076] s2=cos(2πf2t-πkt 2 )

[0077] The bandwidth of the frequency-modulated signal ranges from f1 to f2, where f1<f2, k = bw / T, bw is the signal bandwidth, T is the signal pulse width, and f1 and f2 are the carrier frequencies.

[0078] Step 102: after reflection by the target, the signal received by the first channel is y1, and the signal received by the second channel is y2.

[0079] When receiving starts, the acoustic signal reflected by the target and received by the first channel is y1, and the acoustic signal reflected by the target and received by the second channel is y2, and both acoustic signals usually contain noise.

[0080] Step 103: perform down-conversion mixing processing on the received signals y1 and y2.

[0081] Down-conversion mixing is performed on the received signals. The purpose of down-conversion mixing is to shift the high-frequency signal to a low frequency, and the mixing formula is as follows:

[0082] y DDC1 = y1·cos(2πf1t)-1j·y1·sin(2πf1t)

[0083] y DDC2 = y2·cos(2πf1t)-1j·y2·sin(2πf1t)

[0084] Mixing will produce a real part and an imaginary part, so all subsequent signals are complex signals.

[0085] Step 104: perform low-pass filtering on the signals after down-conversion mixing processing.

[0086] According to the sampling theorem, mixing will cause an image frequency problem, so low-pass filtering is performed on the down-converted mixed signals, and the filtered signals are y respectively LP1 and y LP2 .

[0087]

[0088] wherein, * is a convolution operation, f c is the cut-off frequency of the filter.

[0089] Step 105: perform downsampling on the low-pass filtered signals.

[0090] Downsampling is performed on the signals after low-pass filtering processing, which reduces computational complexity and data rate while keeping important signal features unchanged. The output signals are y respectively DSR1 and y DSR2 , the downsampling rate can be adjusted according to hardware requirements, and the formula is as follows:

[0091]

[0092] Wherein, DSR is the sampling rate, which is an integer, indicating that one data point is taken every DSR sampling points.

[0093] Step 106: Perform pulse compression on the downsampled signal.

[0094] To improve distance resolution and increase the signal-to-noise ratio, pulse compression is employed, and the two signal paths are matched with the local signal separately. The complex convolution formula is as follows:

[0095] y mf1_re =y DSR1_re *F 1_re -y DSR1_im *F 1_im

[0096] y mf1_im =y DSR1_re *F 1_im +y DSR1_im *F 1_re

[0097] y mf2_re =y DSR2_re *F 2_re -y DSR2_im *F 2_im

[0098] y mf2_im =y DSR2_re *F 2_im +y DSR2_im *F 2_re

[0099] Among them, y mf1 With y mf2 The output signal after matched filtering is a complex signal:

[0100] y mf1 =y mf1_re +1j·y mf1_im

[0101] y mf2 =y mf2_re +1j·y mf2_im

[0102] y mf1_re and y mf2_re Let y be the real part of the signal. mf1_im With y mf2_im This represents the imaginary part of the signal.

[0103] F1 and F2 are local signals, that is, signals obtained by processing the ideal transmitted signals s1 and s2 in the same way as the received signals, and are also complex signals:

[0104] F1 = F 1_re +1j·F 1_im

[0105] F2 = F 2_re +1j·F 2_im

[0106] F 1_re and F 2_re F is the real part of the signal. 1_im With F 2_im The imaginary part of the signal

[0107] Step 107: Obtain the envelope of the pulse-compressed signal.

[0108] The envelope of the pulse-compressed signal is obtained by taking the modulus of a complex number, i.e., by the following formula:

[0109]

[0110] Among them, z1 and z2 are the data obtained after envelope calculation. Because the data has undergone pulse compression, the signal-to-noise ratio is high, and it is purer and more reliable. Therefore, when it is transmitted to the host computer for interface display, the influence of noise and other non-target objects is smaller, and the interface is clearer and more understandable for the user.

[0111] Simulation and Experimental Testing

[0112] The simulation used a single transducer with a length of 14cm. The directivity of this transducer was simulated based on linear array beamforming, with an element spacing of approximately λ / 2, where λ is the wavelength. The directivity amplitude at 22.5° is related to the frequency of the FM signal and decreases by approximately -35dB relative to the main lobe. The amplitude varies with frequency as follows: Figure 4 As shown.

[0113] During the simulation, the transmitted signal pulse width was 0.1ms. The signals received by the analog receiver from the first channel (the channel transmitting the positive frequency modulated signal) at 0° and 22.5° were s1 and s2, respectively. 1_225 (Ideally, no noise or channel loss should be added for now), for s1 and s 1_225 The envelopes are obtained by performing matched filtering with F1 and F2 respectively. Figure 5 As shown.

[0114] Depend on Figure 5 It can be seen that the main lobe amplitude after s1 and F1 are matched is similar to s1. 1_225 The main lobe amplitude differs from that of F1 by approximately 40 dB. 1_225 The maximum amplitude after matching with F1 and s 1_225The main lobe amplitude differs by about 10 dB after matching with F1. The maximum amplitude after matching with F2 (purple line) differs by about 10 dB from the main lobe amplitude after matching with F1 (blue line).

[0115] In other words, compared to a single-channel transducer, a dual-channel transducer using positive and negative frequency modulation signals has less impact on the first transducer during signal processing.

[0116] Relevant tests were conducted in the anechoic water tank, with the transducer automatically transmitting and receiving signals. The test results are as follows: Figure 6 As shown, the results indicate that the directivity amplitude of the first channel at 22.5° is reduced by approximately -24 dB compared to 0°, and the main lobe amplitude after s1 and F1 matching is similar to that of s1. 1_22 The main lobe amplitudes of F5 and F1 matched products differ by approximately 25 dB, even if s 1_225 After matching with F2, there is no significant amplitude, but the maximum amplitude is similar to s. 1_225 The main lobe amplitude differs from that of F1 by about 10dB. Due to errors introduced during the manufacturing process of the transducer, the transducer directivity amplitude in the 22.5° direction is -24dB, which is about 10dB higher than the simulation. Therefore, it will have a certain impact on the measured matching results.

[0117] Based on the same inventive concept, this application also provides a dual-channel positive and negative frequency modulation signal processing apparatus for implementing the dual-channel positive and negative frequency modulation signal processing method described above. The solution provided by this apparatus is similar to the implementation scheme described in the above method. Therefore, the specific limitations of one or more dual-channel positive and negative frequency modulation signal processing apparatus embodiments provided below can be found in the limitations of the dual-channel positive and negative frequency modulation signal processing method described above, and will not be repeated here.

[0118] In one exemplary embodiment, a dual-channel positive and negative frequency modulation signal processing device is provided, comprising:

[0119] The signal acquisition module is used to transmit a positive frequency modulation signal s1 and a negative frequency modulation signal s2 to the target using the first and second channels of the dual-channel transducer, respectively.

[0120] After being reflected by the target, the signal acquisition module receives signal y1 through the first channel and signal y2 through the second channel.

[0121] The downmixing module is used to perform downmixing processing on the received signals y1 and y2.

[0122] The low-pass filter module is used to perform low-pass filtering on the signal after down-mixing.

[0123] The downsampling module is used to downsample the low-pass filtered signal;

[0124] The pulse compression module is used to compress the downsampled signal into pulses.

[0125] The envelope acquisition module is used to acquire the envelope of the pulse-compressed signal.

[0126] In summary, the above-mentioned solution in this application has the following beneficial effects:

[0127] Traditional transmission methods involve transmitting the same signal to each channel, such as simultaneously transmitting signals from the first and second channels. When the signal reaches the target, it is reflected back to the first and second channels, at which point the receivers of the first and second channels begin to operate. A portion of the signal from the first channel will enter the second channel. If pulse compression is applied, a peak will be generated. This result will affect the judgment of target location and number. For example, if an object is close to the sound emitted by the first channel, but because the transmissions from the first and second channels are consistent with the pre-stored signals, when the sound wave reaches the target, its echo will not only produce a peak after pulse compression with the first channel, but also a peak after pulse compression with the second channel. In the host computer interface display, what was originally a single bright spot will appear as two bright spots due to interference from the second channel.

[0128] This application effectively avoids this problem. For example, if the first channel transmits a positive frequency modulated signal, and the receiving link of the first channel also stores a positive frequency modulated signal, while the second channel transmits a negative frequency modulated signal, and the receiving link of the second channel also stores a negative frequency modulated signal, then when the target is near the sound ray of the first channel, the signal transmitted by the first channel, after reflection, can only effectively compress the pulse with the local signal of the first channel and produce a single peak value, but cannot produce a peak value with the local signal in the second channel. Therefore, the host computer user interface will only display one bright spot.

[0129] In one exemplary embodiment, a computer device is provided, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 7As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores dual-channel positive and negative frequency modulation signal processing data. The I / O interfaces are used for information exchange between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a dual-channel positive and negative frequency modulation signal processing method.

[0130] Those skilled in the art will understand that Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0131] In one exemplary embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0132] In one exemplary embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0133] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0134] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0135] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0136] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0137] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0138] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A signal processing method with dual-channel positive and negative frequency modulation, characterized in that, The dual-channel positive and negative frequency modulation signal processing method includes: The first and second channels of the dual-channel transducer respectively transmit positive frequency modulation signals to the target. and negative frequency modulation signal ; After being reflected by the target, the signal received by the first channel is The signal received by the second channel is ; For the received signal and Perform downmixing; Low-pass filtering is applied to the signal after downmixing. Downsampling is performed on the low-pass filtered signal; Pulse compression is performed on the downsampled signal; The envelope of the pulse-compressed signal is obtained. The positive frequency modulation signal The expression is: ; negative frequency modulation signal The expression is: ; in, and The carrier frequency is and the bandwidth of the frequency modulation signal is . ,and , k = bw / T , bw For signal bandwidth, T For signal pulse width, t Sampling time; The received signal and The following formula is used specifically for downmixing: ； ； in, This represents the complex signal generated by the first channel after downmixing. This represents the complex signal generated by the second channel after downmixing. and For carrier frequency, j Indicates the imaginary part; Pulse compression of the downsampled signal specifically involves using a local complex signal pre-stored in the receiving link of the first channel. and the local signal pre-stored in the receiving link of the second channel Perform pulse compression.

2. The dual-channel positive and negative frequency modulation signal processing method according to claim 1, characterized in that, The specific formula for low-pass filtering the signal after down-mixing is as follows: ； ； in, This represents the complex signal output from the first channel after passing through the low-pass filter. This represents the complex signal output from the second channel after passing through the low-pass filter. This represents the complex signal output from the first channel after downmixing. ， This represents the complex signal output from the second channel after downmixing. Indicates the cutoff frequency of the filter. Indicates the sampling time. This is a convolution operation.

3. The dual-channel positive and negative frequency modulation signal processing method according to claim 1, characterized in that, The downsampling of the low-pass filtered signal is specifically performed using the following formula: ； ； in, This represents the complex signal output from the first channel after downsampling. This represents the complex signal output from the second channel after downsampling. This represents the complex signal output from the first channel after processing by the low-pass filter. This represents the complex signal output from the second channel after processing by the low-pass filter. Indicates the downsampling rate. Indicates the sampling time.

4. The dual-channel positive and negative frequency modulation signal processing method according to claim 1, characterized in that, The pulse compression of the downsampled signal is specifically performed using the following formula: ； ； ； ； in, This represents the complex signal output from the first channel after pulse compression. This represents the complex signal output from the second channel after pulse compression. This represents the real part of the complex signal output from the first channel after downsampling. This represents the real part of the complex signal output from the second channel after downsampling. This represents the imaginary part of the complex signal output from the first channel after downsampling. This represents the imaginary part of the complex signal output from the second channel after downsampling. ； ； This represents the real part of the complex signal output from the first channel after pulse compression. This represents the real part of the complex signal output from the second channel after pulse compression. This represents the imaginary part of the complex signal output from the first channel after pulse compression. This represents the imaginary part of the complex signal output from the second channel after pulse compression. This is a local complex signal pre-stored in the receiving link of the first channel. For the local signal pre-stored in the receiving link of the second channel: ； ； The real part of the local complex signal pre-existing in the receiving link of the first channel. The real part of the local complex signal pre-existing in the receiving link of the second channel. The imaginary part of the local complex signal pre-existing in the receiving link of the first channel. It is the imaginary part of the local complex signal pre-existing in the receiving link of the second channel.

5. The dual-channel positive and negative frequency modulation signal processing method according to claim 1, characterized in that, The envelope of the pulse-compressed signal is obtained using the following formula: ； ； in, This represents the output signal of the first channel after envelope calculation. This represents the output signal of the second channel after envelope calculation. This represents the real part of the complex signal output from the first channel after pulse compression. This represents the imaginary part of the complex signal output from the first channel after pulse compression. This represents the real part of the complex signal output from the second channel after pulse compression. This represents the imaginary part of the complex signal output from the second channel after pulse compression.

6. A dual-channel positive and negative frequency modulation signal processing device, characterized in that, The dual-channel positive and negative frequency modulation signal processing device includes: The signal acquisition module is used to transmit positive frequency modulated signals to the target using the first and second channels of the dual-channel transducer, respectively. and negative frequency modulation signal ; The signal acquisition module receives the signal through the first channel after reflection from the target. The signal received by the second channel is ; The downmixing module is used to process the received signal. and Perform downmixing; The low-pass filter module is used to perform low-pass filtering on the signal after down-mixing. The downsampling module is used to downsample the low-pass filtered signal; The pulse compression module is used to compress the downsampled signal into pulses. The envelope acquisition module is used to acquire the envelope of the pulse-compressed signal. The positive frequency modulation signal The expression is: ; negative frequency modulation signal The expression is: ; in, and The carrier frequency is and the bandwidth of the frequency modulation signal is . ,and , k = bw / T , bw For signal bandwidth, T For signal pulse width, t Sampling time; The received signal and The following formula is used specifically for downmixing: ； ； in, This represents the complex signal generated by the first channel after downmixing. This represents the complex signal generated by the second channel after downmixing. and For carrier frequency, j Indicates the imaginary part; Pulse compression of the downsampled signal specifically involves using a local complex signal pre-stored in the receiving link of the first channel. and the local signal pre-stored in the receiving link of the second channel Perform pulse compression.

7. A computer device, comprising: The memory and processor contain a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the steps of the dual-channel positive and negative frequency modulation signal processing method according to any one of claims 1-5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the steps of the dual-channel positive and negative frequency modulation signal processing method as described in any one of claims 1-5.

9. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the steps of the dual-channel positive and negative frequency modulation signal processing method as described in any one of claims 1-5.

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