Joint transmission and reception optimization method and device for radar complementary polyphase coded frequency modulation signals

Abstract

The application relates to a radar complementary polyphase coded frequency modulation signal joint transmission and reception optimization method and device. A complementary polyphase coded frequency modulation signal preset is transmitted to a target area through each channel of a transmitting end, a target echo signal received at a receiving end is filtered by using a preset receiving filter set, a transmission-reception joint optimized waveform is obtained, and accurate detection of the target is realized according to the waveform.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of radar waveform generation, in particular to a radar complementary multi-phase coded frequency modulation signal joint transmission and reception optimization method and device. BACKGROUND

[0002] In MIMO radar, in order to avoid mutual interference between different channels, it is generally required that the set of transmitted waveforms has good orthogonality. In order to make the radar system have better moving target detection performance and clutter suppression ability, it is also required that the transmitted waveform has good autocorrelation performance and Doppler tolerance. The existing MIMO radar transmitted waveform design work is mostly based on phase coded waveforms. Although the phase coded waveform has high waveform design freedom, due to the existence of sharp phase jump between different sub-pulses, it has high requirements for the transmitter in practical application, and it is usually difficult to achieve the theoretical performance. In addition, the research scope of the existing MIMO radar transmitted waveform design work is usually concentrated in one pulse repetition period, ignoring the superiority of multi-pulse joint in the coherent processing interval. SUMMARY

[0003] Therefore, it is necessary to provide a radar complementary multi-phase coded frequency modulation signal joint transmission and reception optimization method and device which can effectively improve target detection for the above technical problems.

[0004] A radar complementary multi-phase coded frequency modulation signal joint transmission and reception optimization method, the method is implemented in the transmitting end and the receiving end of a radar system, comprising:

[0005] Each channel of the transmitting end transmits a pre-set complementary multi-phase coded frequency modulation signal to a target area;

[0006] After the receiving end receives the target echo signal, the target echo signal is filtered by using a pre-set receiving filter set to obtain a filtered echo signal, and target detection is performed according to the filtered echo signal;

[0007] The pre-set complementary multi-phase coded frequency modulation signal and the parameters of the receiving filter set are obtained by solving a transmit-receive joint optimization model.

[0008] In one embodiment, when the transmit-receive joint optimization model is constructed:

[0009] The complementary multi-phase coded frequency modulation signal of each channel and the parameters of the receiving filter are taken as variables to be optimized;

[0010] The sidelobes of the complementary auto-misunderstanding function and the mutual misunderstanding function in the distance-Doppler interval of interest are taken as the optimization objective function, and the total energy of the receiving filter set is constant as the constraint condition;

[0011] constructing the transmit-receive joint optimization model according to the variable to be optimized, the optimization objective function and the constraint condition.

[0012] In one embodiment, the transmit-receive joint optimization model is expressed as:

[0013]

[0014] wherein,

[0015] In the above formula, f(s, w) represents the sidelobes and of the auto- and cross- ambiguity functions of the baseband complementary transmit waveform and the receive filter set in the distance-Doppler interval of interest, x represents the baseband transmit waveform, w represents the receive filter, represents the receive filter parameter corresponding to the i-th pulse in the q-th channel, the superscript H represents conjugate transpose, represents the i-th pulse transmit signal of the q-th channel of the radar system, represents the i-th pulse baseband transmit signal of the q-th channel, G represents the beamforming matrix converted from the baseband signal to the transmit signal, represents a weight factor, h represents a Doppler unit, is the Doppler interval of interest, d is the distance unit, is the distance interval of interest, p represents a positive integer, represents the correlation function of the i-th pulse of the q-th and q'-th channels at the Doppler shift h, (·) * represents conjugate, ||·||p p represents p-norm, F represents Fourier transform matrix, I represents the number of pulses in each channel, and Q represents the number of channels of the radar system.

[0016] In one embodiment, when solving the transmit-receive joint optimization model:

[0017] the parameters of the receive filter set in the transmit-receive joint optimization model are fixed, the L-BFGS algorithm is used to update the baseband transmit waveform of each pulse of each channel, and the corresponding complementary polyphase coded frequency modulation signal is obtained according to the baseband transmit waveform;

[0018] the complementary polyphase coded frequency modulation signal is brought into the transmit-receive joint optimization model, and the MM algorithm is used to solve the parameters of the receive filter set;

[0019] the parameters of the baseband transmit waveform and the receive filter set in the transmit-receive joint optimization model are alternately iteratively solved until convergence, and the optimized complementary polyphase coded frequency modulation signal and the receive filter set parameters are obtained.

[0020] In one embodiment, when updating the baseband transmit waveform of each pulse of each channel respectively by using the L-BFGS algorithm, the derivative information of the objective function with respect to the to-be-optimized variable is solved by using the following formula:

[0021]

[0022] In the above formula,

[0023] indicates the weighted correlation function of the i th pulse of the q th and q' th channels at the Doppler shift h, F indicates a Fourier transform matrix, indicates the zero-padded receive filter parameter of the i th pulse of the q th channel at the Doppler shift h.

[0024] In one embodiment, when alternately iteratively solving the parameters of the baseband transmit waveform and the receive filter set in the transmit-receive joint optimization model, the iteration termination condition is:

[0025]

[0026] or the number of iterations is greater than a preset number threshold value;

[0027] In the above formula, the superscript z indicates the number of iterative solutions, and ε0 indicates a preset convergence threshold value.

[0028] The application also provides a radar complementary polyphase coded frequency modulation signal joint transmission and reception optimization device, the device comprising:

[0029] A transmitting module is configured to transmit a preset complementary polyphase coded frequency modulation signal to a target area by each channel of the transmitting end.

[0030] A receiving module is configured to filter a target echo signal by using a preset receive filter set after the target echo signal is received by the receiving end, to obtain a filtered echo signal, and to perform target detection according to the filtered echo signal.

[0031] A complementary optimization module is configured to obtain a transmit-receive joint optimization model by solving parameters of the preset complementary polyphase coded frequency modulation signal and the receive filter set.

[0032] A computer device comprises a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0033] Each channel of the transmitting end transmits a preset complementary polyphase coded frequency modulation signal to a target area.

[0034] The receiving end receives the target echo signal, filters the target echo signal by using a pre-set receiving filter set to obtain a filtered echo signal, and performs target detection according to the filtered echo signal.

[0035] The pre-set complementary poly-phase coded frequency modulation signal and the parameters of the receiving filter set are obtained by solving a transmit-receive joint optimization model.

[0036] A computer readable storage medium has a computer program stored thereon, and the computer program is executed by a processor to implement the following steps:

[0037] The transmitting end transmits a pre-set complementary poly-phase coded frequency modulation signal to a target area through each channel.

[0038] The receiving end receives the target echo signal, filters the target echo signal by using a pre-set receiving filter set to obtain a filtered echo signal, and performs target detection according to the filtered echo signal.

[0039] The pre-set complementary poly-phase coded frequency modulation signal and the parameters of the receiving filter set are obtained by solving a transmit-receive joint optimization model.

[0040] The radar complementary poly-phase coded frequency modulation signal joint transmission and reception optimization method and device transmit a pre-set complementary poly-phase coded frequency modulation signal to a target area through each channel of the transmitting end, filter a received target echo signal by using a pre-set receiving filter set to obtain a transmit-receive joint optimized waveform, and perform accurate target detection according to the waveform. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 It is an application environment diagram of the radar complementary poly-phase coded frequency modulation signal joint transmission and reception optimization method in one embodiment;

[0042] Figure 2 It is a target function convergence curve diagram with different p values in a simulation experiment;

[0043] Figure 3 It is a self-blurring function diagram of transmitting channel 1 and receiving channel 1 in a simulation experiment;

[0044] Figure 4 It is a cross-blurring function diagram of transmitting channel 1 and receiving channel 2 in a simulation experiment;

[0045] Figure 5 It is a cross-blurring function diagram of transmitting channel 2 and receiving channel 1 in a simulation experiment;

[0046] Figure 6 Fig. 2 is a schematic diagram of a self-blurring function of a transmitting channel 2 and a receiving channel 2 in an experimental simulation;

[0047] Figure 7 Fig. 4 is a structural block diagram of a joint transmitting and receiving optimization device of a radar complementary poly-phase coded frequency modulation signal in an embodiment;

[0048] Figure 8 Fig. 5 is an internal structural diagram of a computer device in an embodiment. DETAILED DESCRIPTION

[0049] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0050] In the existing radar waveform design, the design based on phase coding waveform has high design freedom, but it is difficult to achieve the theoretical performance due to the high requirement on the transmitter caused by the sharp phase jump between different sub-pulses. At the same time, the range of waveform design is often concentrated in one pulse repetition period, ignoring the superiority of multi-pulse joint in the coherent processing interval, such as Figure 1 As shown in Fig. 1, a radar complementary poly-phase coded frequency modulation signal joint transmitting and receiving optimization method is provided, which is implemented in the transmitting end and the receiving end of a radar system, and specifically includes the following steps:

[0051] Step S100, each channel of the transmitting end transmits a pre-set complementary poly-phase coded frequency modulation signal to a target area.

[0052] Step S110, after the receiving end receives the target echo signal, the target echo signal is filtered by using a pre-set receiving filter set to obtain a filtered echo signal, and target detection is performed according to the filtered echo signal.

[0053] Step S120, the pre-set complementary poly-phase coded frequency modulation signal and the parameters of the receiving filter set are used to solve a transmitting-receiving joint optimization model.

[0054] In the present application, a joint optimization method complementary in the receiving end and the transmitting end is adopted in the radar system to realize accurate detection of targets. Specifically, a multi-phase coded frequency modulation baseband complementary transmitting waveform is adopted in the transmitting end, which can make the transmitting signal have better autocorrelation and cross-correlation characteristics, reduce channel interference, and the receiving filter set in the receiving end can further filter out noise and interference. The combination of the two can effectively improve the quality of the received target echo signal. The parameters of the pre-set baseband complementary transmitting waveform and the receiving filter set are obtained by solving the transmit-receive joint optimization model, which means that the design of the transmitting waveform is matched with the receiving end filtering processing, which can make the target echo signal more prominent in detection, improve the detection probability of the target, more accurately identify the target, and also improve the detection performance of the moving target and the clutter suppression ability, optimize the detection effect. In addition, the joint optimization makes the transmitting end and the receiving end work cooperatively, makes the resource utilization of the whole MIMO radar system more efficient, reduces unnecessary resource waste, and improves the overall performance and working efficiency of the system.

[0055] In the present embodiment, when constructing the transmit-receive joint optimization model: the multi-phase coded frequency modulation baseband complementary transmitting waveform of each channel and the parameters of the receiving filter are taken as variables to be optimized, the sidelobes of the complementary self-mobility function and the mutual mobility function in the distance-Doppler interval of interest are taken as the optimization objective function, and the total energy of the receiving filter set is constant as the constraint condition. Finally, the transmit-receive joint optimization model is constructed according to the variables to be optimized, the optimization objective function and the constraint condition.

[0056] In the present embodiment, it is assumed that the transmitting signal of the PCFM-MIMO radar system is where M is the length of the single pulse transmitting waveform of each channel, I is the number of pulses contained in the pulse repetition period, and Q is the number of channels. It is assumed that the baseband transmitting waveform is where N is the length of the single pulse baseband transmitting waveform of each channel. The relationship between the transmitting signal of the radar system and the baseband transmitting waveform, i.e., the transmitting signal after PCFM modulation, is represented as:

[0057]

[0058] In formula (1), respectively represent the transmitting signal and the baseband transmitting waveform of the i-th pulse in the q-th channel. M=KN, K is the oversampling multiple. j is the imaginary unit, G represents the beamforming matrix converted from the baseband signal to the transmitting signal. Specifically, G=[g1, g2, …, g N ].

[0059] Further,

[0060] g n =[g n (1), gn (2),…,g n (M)],n=1,2,…M (2)

[0061] Further,

[0062] The auto- and cross-ambiguity functions of the complementary transmit waveform and receive filter set at the sidelobes and f(s,w) in the distance-Doppler region of interest can be expressed as:

[0063]

[0064] In equation (4), h represents the Doppler bin, represents the Doppler bin of interest, d represents the distance bin, represents the distance bin of interest, p represents a positive integer. and is a weight factor.

[0065] Specifically, for the value of when q = q', i.e., in the summation process, if the two summed channels are equal, and , otherwise, is used to extract the distance bins of interest in the correlation function, when the index is within the distance bin of interest interval, the element under the index takes the value of 1, otherwise it takes the value of 0.

[0066] Further, in equation (4), (·) * represents the conjugate, ||·||p p represents the p-norm. represents the correlation function of the ith pulse of the qth and q'th channels at the Doppler shift h, which can be expressed as:

[0067]

[0068] In equation (5), F is the Fourier transform matrix, and:

[0069]

[0070] After equation (5) is brought into equation (4), we can get:

[0071]

[0072] Therefore, the optimization model for jointly designing the PCFM transmit waveform and receive filter set with high Doppler tolerance, i.e., the transmit-receive joint optimization model, can be expressed as:

[0073]

[0074] where the energy constraint on the receive filter is to reduce the mismatched SINR loss due to the transmit waveform and receive filter mismatch.

[0075] In the embodiment, when solving the transmit-receive joint optimization model, the parameters of the receive filter set in the transmit-receive joint optimization model are fixed first, and the baseband transmit waveform of each channel and each pulse, i.e., in formula (1) is updated respectively by using the L-BFGS algorithm. And the corresponding pulse coded frequency modulation waveform, i.e., in formula (1) is obtained according to the baseband transmit waveform. Then the pulse coded frequency modulation waveform is brought into the transmit-receive joint optimization model, the parameters of the receive filter set are solved by using the MM algorithm, the baseband transmit waveform and the parameters of the receive filter set in the transmit-receive joint optimization model are solved alternately and iteratively until convergence, and the optimized baseband complementary transmit waveform and the parameters of the receive filter set are obtained.

[0076] Next, the solving of the baseband transmit waveform and the parameters of the receive filter set is described respectively.

[0077] In the embodiment, when solving the baseband transmit waveform based on the transmit-receive joint optimization model, the parameters of the receive filter set in the transmit-receive joint optimization model are fixed first, that is, the baseband transmit waveform is solved as an unknown, and then the transmit-receive joint optimization model is converted into a problem model for solving the baseband transmit waveform, which is represented as:

[0078]

[0079] Since the problem model has a complex high-order objective function and is a strong non-convex optimization problem, the Limited Memory Broyden Fletcher Goldfarb and Shanno (L-BFGS) algorithm is used to solve the above optimization problem. In the L-BFGS algorithm, the derivative information of the objective function with respect to the optimization variable needs to be solved.

[0080] Further, when solving the derivative information of the objective function with respect to the optimization variable, the objective function in the problem model is rewritten as:

[0081]

[0082] The partial derivative of each summation term with respect to can be written as:

[0083]

[0084] Meanwhile, we can derive:

[0085]

[0086] Combining equation (5) and equation (13), we can get:

[0087]

[0088] Further, combining equation (12) and equation (14), we can get:

[0089]

[0090] where,

[0091] Specifically, equation (15) is the partial derivative of the objective function with respect to one code in the baseband transmit signal, and the partial derivative of the single-channel monopulse baseband transmit waveform can be written as a column connection arrangement of the partial derivatives of different codes, which is denoted as:

[0092]

[0093] Therefore, combining equation (11) and equation (17), the partial derivative of the objective function with respect to the single-channel monopulse baseband transmit signal waveform can be expressed as:

[0094]

[0095] In equation (18),

[0096] represents the weighted correlation function of the ith pulse of the qth and q' th channels at the Doppler shift h, and F represents the Fourier transform matrix, represents the zero-padded receive filter parameter of the ith pulse of the qth channel at the Doppler shift h.

[0097] Using equation (18) to solve the partial derivative of f(s) with respect to the baseband signal of each pulse of each transmit channel, the derivative information is substituted into the L-BFGS algorithm to update the baseband transmit signal of each pulse of each transmit channel, and finally the PCFM transmit waveform is updated using equation (1).

[0098] In this embodiment, when solving the parameters in the receive filter set, the solved PCFM transmit waveform is brought into the transmit-receive joint optimization model and is fixed, that is, the parameters in the receive filter set are solved as unknown data, and at this time the transmit-receive joint optimization model can be written as:

[0099]

[0100] where,

[0101] In formula (20), This is a weighting coefficient, which takes a value of 0 when the conditions q = q', d = 0, and h is within the distance of interest-Doppler cell; otherwise, it takes a value of 1. d Let be a displacement matrix, and the element in the a-th row and b-th column is:

[0102]

[0103] Furthermore, in order to transform the problem formula (19) into a form solvable by the Majorization-Minimization (MM) algorithm, an upper bound function of the original problem is constructed by introducing auxiliary variables, where the introduced auxiliary variables are expressed as:

[0104]

[0105] In formula (24), M I =I(2M-1), therefore formula (20) can be transformed into:

[0106]

[0107] Furthermore, the transmit waveforms of each channel and the parameters of the receive filter bank are combined into a single variable, as follows:

[0108]

[0109] Its relationship with the single-channel transmit waveform and receive filter is as follows:

[0110]

[0111] In formulas (28) and (29), T is the block selection matrix, which is defined as:

[0112]

[0113] Formula (25) can then be further transformed into:

[0114]

[0115] Based on the properties of the matrix trace, formula (31) can be derived as follows:

[0116]

[0117] In formula (32),

[0118] After finding the upper bound function of formula (32), the problem model formula (19) can be converted into:

[0119]

[0120] Specifically, when the qth channel receiving filter parameter is optimized alone, the corresponding sub-problem model can be written as:

[0121]

[0122] In formula (34), By defining the matrix K, can be expressed as K is an M I dimensional matrix, which is defined as:

[0123]

[0124] Therefore, the problem model formula (34) can be finally converted into:

[0125]

[0126] wherein,

[0127]

[0128] Since, in formula (37), K is a Hermitian matrix, the problem model is a quadratic equality constraint linear optimization problem, and the closed-form optimization solution can be written as:

[0129]

[0130] wherein,

[0131]

[0132] In this embodiment, based on the transmit-receive joint optimization model, the above method is used to continuously perform alternating iteration on the transmit-receive joint optimization model until the iteration termination condition is met.

[0133] In this embodiment, the iteration termination condition is:

[0134]

[0135] Or, the iteration number is greater than the preset number threshold, that is, z>z0;

[0136] In the above formula, the superscript z represents the iteration solving number, z0 represents the preset number threshold, and ε0 represents the preset convergence threshold. ​​

[0137] In this paper, the effectiveness of the proposed method is also demonstrated through simulation experiments.

[0138] In the simulation experiment, the optimization problem parameters are first determined: following the steps of constructing the transmit-receive joint optimization model in this method, it is assumed that the radar system has M = 2 transmit signal channels, bandwidth B = 100MHz, phase coding code length N = 64, and carrier frequency f. s =14GHz, the normalized range range of the target is [-3,3], and the normalized Doppler frequency range is [-3,3]. The possible angle of the target in the airspace is [30°, 40°], and the possible angle of clutter in the airspace is [-90°, 30°)∪(40°, 90°). The frequency response of the target within the radar operating bandwidth is an all-1 vector, and the power spectrum characteristics of the clutter are as follows. Figure 2 As shown.

[0139] Next, the optimal energy spectrum of the transmission sequence for each channel is solved: the optimal transmission waveform energy spectrum for each channel is solved using the water-filling method, such as... Figure 3 As shown.

[0140] Furthermore, using the MIMO radar transmission sequence set as the optimization variable, the objective function is to minimize the sidelobes of the non-periodic autocorrelation function of each transmission sequence to be optimized within a specific range-Doppler interval. Meanwhile, the constraints are the angular energy ratio between the target and clutter in the transmission pattern of the transmission sequence set to be optimized, the minimum mean square error between the waveform spectrum of the sequence set to be optimized and the ideal spectrum, and constant mode constraints, thus constructing a non-convex optimization model.

[0141] Finally, the non-convex optimization model is solved by transforming the problem model into a convex approximation and using an accelerated continuous convex approximation algorithm to iteratively solve the non-convex optimization model, thereby obtaining the MIMO radar transmission sequence set.

[0142] The specific implementation process of the above steps has been explained above and will not be repeated here. The following numerical simulation experiments further illustrate the beneficial effects of the method of the present invention:

[0143] Establish an optimization problem model: Determine the number of radar system transmission signal channels Q = 2, the number of pulses per channel I = 2, the time-bandwidth product T = 32, the oversampling factor K = 2, and the range of interest cells. Interesting Doppler unit Figure 2 The normalized convergence curves of the objective function f(s,w) for different norm values ​​p show that the algorithm has good convergence for different norm values; and the convergence speed of the objective function increases with the increase of p value. Figure 3 , Figure 4 , Figure 5 , Figure 6The self-clutter function and the mutual-clutter function of different transmitting and receiving channels are shown in the table, and it can be seen that the designed PCFM transmitting waveform and the receiving filter set have deep recesses in the interested range-Doppler unit.

[0144] In the radar complementary polyphase coded frequency modulation signal joint transmitting and receiving optimization method, a transmitting-receiving joint optimization model is established by taking the polyphase coded frequency modulation baseband complementary transmitting waveforms of each channel and the receiving filter as optimization variables, taking the sidelobes of the complementary self-clutter function and the mutual-clutter function in the interested range-Doppler interval as the optimization objective function, and taking the constant total energy of the receiving filter as the constraint condition. When the baseband transmitting waveform is solved based on the transmitting-receiving joint optimization model, the parameters of the receiving filter are fixed, the L-BFGS algorithm is used to update the baseband transmitting waveform of each pulse of each channel, then the PCFM transmitting waveform is updated, the updated PCFM transmitting waveform is brought into the transmitting-receiving joint optimization model, the Majorization-Minimization (MM) algorithm is used to convexly approximate the problem, the closed-form solution of the receiving filter is solved and updated, and the parameters of the baseband transmitting waveform and the receiving filter are alternately iterated and solved until the problem converges, and finally the optimization result is output.

[0145] It should be understood that, although Figure 1 the steps in the flowchart of the method are shown in sequence according to the arrows, these steps are not necessarily executed in sequence according to the arrows. Unless otherwise explicitly stated herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, Figure 1 at least part of the steps in the method can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these sub-steps or stages is not necessarily sequential, but can be alternately executed with other steps or sub-steps or stages of other steps.

[0146] In one embodiment, as shown in Figure 7 , a radar complementary polyphase coded frequency modulation signal joint transmitting and receiving optimization apparatus is provided, comprising a transmitting module 200, a receiving module 210 and a complementary optimization module 220, wherein:

[0147] The transmitting module 200 is configured to transmit the pre-set complementary polyphase coded frequency modulation signal to the target area by each channel of the transmitting end.

[0148] The receiving module 210 is configured to, after the target echo signal is received by the receiving end, filter the target echo signal by using a pre-set receiving filter set to obtain a filtered echo signal, and perform target detection according to the filtered echo signal.

[0149] The complementary optimization module 220 is configured to solve a transmit-receive joint optimization model by using the pre-set complementary polyphase coded frequency modulation signal and parameters of the receiving filter set.

[0150] The specific limitations of the radar complementary polyphase coded frequency modulation signal joint transmission and reception optimization apparatus can refer to the limitations of the radar complementary polyphase coded frequency modulation signal joint transmission and reception optimization method described above, and will not be described here. The modules in the radar complementary polyphase coded frequency modulation signal joint transmission and reception optimization apparatus described above can be realized by software, hardware and combinations thereof. The modules described above can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so as to call and execute the operations corresponding to the modules by the processor.

[0151] In one embodiment, a computer device is provided, which can be a terminal, and the internal structure diagram thereof can be as shown in Figure 8 The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The network interface of the computer device is configured to communicate with external terminals through network connection. The computer program is executed by the processor to implement a radar complementary polyphase coded frequency modulation signal joint transmission and reception optimization method. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer overlaid on the display screen, or a key, trackball or touchpad arranged on the shell of the computer device, or an external keyboard, touchpad or mouse, etc.

[0152] Those skilled in the art can understand that Figure 8 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0153] In one embodiment, a computer device is provided, comprising a memory and a processor, the memory storing a computer program, and the processor implementing the following steps when executing the computer program:

[0154] The channels of the transmitting end transmit preset complementary polyphase coded frequency modulation signals to a target region;

[0155] After the receiving end receives the target echo signal, the target echo signal is filtered by using a preset receiving filter set to obtain a filtered echo signal, and target detection is performed according to the filtered echo signal;

[0156] The preset complementary polyphase coded frequency modulation signals and the parameters of the receiving filter set are obtained by solving a transmitting-receiving joint optimization model.

[0157] In one embodiment, a computer readable storage medium is provided, storing a computer program, and the computer program is executed by a processor to implement the following steps:

[0158] The channels of the transmitting end transmit preset complementary polyphase coded frequency modulation signals to a target region;

[0159] After the receiving end receives the target echo signal, the target echo signal is filtered by using a preset receiving filter set to obtain a filtered echo signal, and target detection is performed according to the filtered echo signal;

[0160] The preset complementary polyphase coded frequency modulation signals and the parameters of the receiving filter set are obtained by solving a transmitting-receiving joint optimization model.

[0161] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, storage, databases, or other media in the embodiments provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0162] The technical features of the above embodiments can be combined in any way. In order to make the description simple, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the present application.

[0163] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, some modifications and improvements can be made, which are all within the scope of the present application. Therefore, the scope of the patent of the present application should be subject to the appended claims.

Claims

1. A radar complementary polyphase coded frequency modulation signal joint transceiving optimization method, characterized in that, The method is implemented at a transmitting end and a receiving end of a radar system, and comprises: Each channel of the transmitting end transmits a pre-set complementary polyphase coded frequency modulation signal to a target region; After the receiving end receives a target echo signal, the target echo signal is filtered by using a pre-set receiving filter set to obtain a filtered echo signal, and target detection is performed according to the filtered echo signal; The pre-set complementary polyphase coded frequency modulation signal and the parameters of the receiving filter set are obtained by solving a transmit-receive joint optimization model, wherein, when the transmit-receive joint optimization model is constructed: the complementary polyphase coded frequency modulation signal of each channel and the parameters of the receiving filter are taken as variables to be optimized, the sidelobes of a complementary auto ambiguity function and a cross ambiguity function in a distance-Doppler interval of interest are taken as an optimization objective function, and the total energy of the receiving filter set is taken as a constraint condition, and the transmit-receive joint optimization model is constructed according to the variables to be optimized, the optimization objective function and the constraint condition.

2. The method of claim 1, wherein the radar complementary polyphase coded frequency modulation signal joint transceiving optimization is characterized by, The transmit-receive joint optimization model is represented as: wherein In the above equation, denotes the side-lobes and the auto- and cross-ambiguities of the baseband complementary transmit waveform and the receive filter set in the distance-Doppler interval of interest, denotes the baseband transmit waveform, denotes the receive filter, denotes the channel The th pulse corresponds to the receive filter parameter, the superscript H denotes the conjugate transpose, denotes the th channel of the radar system, denotes the th pulse transmit signal of the th channel, denotes the th pulse baseband transmit signal of the th channel, denotes the steering matrix from baseband signal to transmit signal, , denotes the weight factor, denotes the Doppler unit, is the Doppler interval of interest, is the distance unit, is the distance interval of interest, denotes the positive integer, denotes the th pulse of the th channel at a Doppler shift of denotes the conjugate, denotes the norm, denotes the Fourier transform matrix, denotes the number of pulses within each channel, denotes the number of channels of the radar system.

3. The radar complementary polyphase coded frequency modulation signal transceiver optimization method according to claim 1 or 2, characterized in that, When the transmit-receive joint optimization model is solved: The parameters of the receiving filter set in the transmit-receive joint optimization model are fixed, the baseband transmit waveform of each pulse of each channel is updated by using an L-BFGS algorithm, and the corresponding complementary polyphase coded frequency modulation signal is obtained according to the baseband transmit waveform; The complementary polyphase coded frequency modulation signal is brought into the transmit-receive joint optimization model, and the parameters of the receiving filter set are solved by using an MM algorithm; The baseband transmit waveform and the parameters of the receiving filter set in the transmit-receive joint optimization model are alternately iteratively solved until convergence, and the optimized complementary polyphase coded frequency modulation signal and the receiving filter set parameters are obtained.

4. The radar complementary poly-phase coded frequency modulation signal transceiver optimization method of claim 3, wherein, When the baseband transmit waveform of each pulse of each channel is updated by using the L-BFGS algorithm, the following formula is used to solve the derivative information of the objective function with respect to the variables to be optimized: In the above formula, denotes the th pulse of the th channel, the weighted correlation function of the th pulse of the th channel at a Doppler shift of denotes the Fourier transform matrix, denotes the th pulse of the th channel after zero padding of the receive filter parameters, denotes the Doppler interval of interest, denotes the weight factor, denotes a positive integer, denotes the steering matrix transforming from baseband signal to transmit signal, denotes the number of pulses within each channel, denotes the conjugate, denotes the th pulse transmit signal of the th channel of the radar system, denotes the th pulse baseband transmit signal of the th channel.

5. The radar complementary polyphase coded frequency modulation signal transceiver optimization method of claim 4, wherein, When the baseband transmit waveform and the parameters of the receiving filter set in the transmit-receive joint optimization model are alternately iteratively solved, the iteration termination condition is: Or, the number of iterations is greater than a pre-set number threshold value. In the above formula, the superscript represents the number of iterations, represents a preset convergence threshold value.

6. A radar complementary polyphase coded frequency modulation signal joint transceiver optimization device, characterized in that, The device comprises: A transmitting module, configured to transmit a pre-set complementary polyphase coded frequency modulation signal to a target region at each channel of a transmitting end; A receiving module, configured to, after a target echo signal is received at a receiving end, filter the target echo signal by using a pre-set receiving filter set to obtain a filtered echo signal, and perform target detection according to the filtered echo signal; a complementary optimization module configured to solve a transmit-receive joint optimization model by using the pre-configured complementary polyphase coded frequency modulation signals and the parameters of the receive filter bank, wherein, in constructing the transmit-receive joint optimization model, the complementary polyphase coded frequency modulation signals of each channel and the parameters of the receive filter are taken as variables to be optimized, a sidelobe of a complementary auto-multipath function and a cross-multipath function in a distance-Doppler region of interest is taken as an optimization objective function, and a total energy of the receive filter bank is taken as a constraint condition, and the transmit-receive joint optimization model is constructed according to the variables to be optimized, the optimization objective function and the constraint condition. 7.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-6 when the computer program is executed by the processor. The computer program, when executed by the processor, implements the steps of the method of any one of claims 1 to 5.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program, when executed by the processor, implements the steps of the method of any one of claims 1 to 5.

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