Methods, apparatus, devices and storage media for generating orthogonal waveforms

Abstract

This application relates to the field of signal processing technology, providing an orthogonal waveform generation method, apparatus, device, and storage medium. The orthogonal waveform generation method includes: determining the number of transmitting elements, the number of receiving elements, and the length of the encoded sequence in an antenna array; constructing constraints for each transmitted signal based on the number of transmitting elements and the length of the encoded sequence; generating the transmitted signal based on the constraints, and radiating it outwards through the transmitting elements for target detection; receiving the transmitted signal carrying target information through the receiving elements; performing matched filtering on the received signal received by the receiving elements, and performing digital beamforming based on the matched-filtered received signal, followed by target detection and outputting target information. This application enables the received signal received by the receiving elements to have low range sidelobes after matched filtering and to perform normal digital beamforming.

Description

Technical Field

[0001] This application belongs to the field of signal processing technology, and in particular relates to an orthogonal waveform generation method, apparatus, device and storage medium. Background Technology

[0002] MIMO (multiple-in multiple-out) radar, as a novel radar system, has received increasing attention in recent years. By designing the transmitted signals of MIMO radar, the orthogonality of the transmitted signals can be used to perform matched filtering on the received radar signals, thereby improving the radar's target detection and tracking capabilities. Currently, commonly used methods for generating transmitted signals using orthogonal phase coding include simulated annealing, genetic algorithms, and minimum cross-entropy methods. However, these methods exhibit high range sidelobes after matched filtering, which is detrimental to target detection and can lead to missed detections or false alarms due to sidelobes on small targets. Summary of the Invention

[0003] This application provides an orthogonal waveform generation method, apparatus, device, and storage medium, which can solve the problem of high distance sidelobes after signal matched filtering in the prior art.

[0004] The first aspect of this application provides an orthogonal waveform generation method, including:

[0005] Determine the number of transmitting elements, the number of receiving elements, and the length of the encoded sequence for the antenna array;

[0006] Based on the number of transmitting array elements and the length of the coding sequence, constraints are constructed for each transmitted signal. The constraints include an orthogonal constraint function, which is used to make each transmitted signal orthogonal to the sum of all transmitted signals.

[0007] The transmitted signal is generated based on the constraints and is radiated outward by the transmitting array element to detect the target. The receiving array element receives the transmitted signal carrying the target information.

[0008] The received signal received by the receiving array element is subjected to matched filtering, and digital beamforming is performed based on the matched filtered received signal. Then, target detection is performed and target information is output.

[0009] A second aspect of this application provides an orthogonal waveform generation apparatus, comprising:

[0010] The information determination module is used to determine the number of transmitting elements, the number of receiving elements, and the length of the encoded sequence of the antenna array;

[0011] The signal constraint module is used to construct constraint conditions for each transmitted signal based on the number of transmitted array elements and the length of the encoded sequence. The constraint conditions include an orthogonal constraint function, which is used to make each transmitted signal orthogonal to the sum of all transmitted signals.

[0012] The signal transmitting module is used to generate the transmitting signal based on the constraints, and to perform target detection by radiating it outward through the transmitting array element, and the receiving array element receives the transmitting signal with target information.

[0013] The waveform generation module is used to perform matched filtering on the received signal received by the receiving array element, perform digital beamforming based on the matched filtered received signal, perform target detection, and output target information.

[0014] A third aspect of this application provides a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the orthogonal waveform generation method described above.

[0015] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the orthogonal waveform generation method described above.

[0016] The orthogonal waveform generation method provided in the first aspect of this application constructs constraints for each transmitted signal, which are used to make each transmitted signal orthogonal to the sum of all transmitted signals. Based on the constraints, the transmitted signal is generated and the target is detected by the outward radiation of the transmitting array element. The receiving array element receives the transmitted signal with target information, which enables the received signal received by the receiving array element to have a low range sidelobe after matched filtering.

[0017] It is understood that the beneficial effects of the second, third and fourth aspects mentioned above can be found in the relevant descriptions in the first aspect above, and will not be repeated here. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A schematic flowchart illustrating the orthogonal waveform generation method provided in an embodiment of this application;

[0020] Figure 2A schematic diagram of a MIMO array provided in an embodiment of this application;

[0021] Figure 3 The non-periodic autocorrelation function graph of the transmitted signal provided in the embodiments of this application;

[0022] Figure 4 This is a diagram of the first type of received signal after matched filtering provided in an embodiment of this application;

[0023] Figure 5 A schematic diagram of a conventional array provided in an embodiment of this application;

[0024] Figure 6 This application provides a first type of array element phase relationship diagram in its embodiments;

[0025] Figure 7 This application provides a first type of DBF pattern for embodiments;

[0026] Figure 8 This is an enlarged view of the first type of DBF pattern provided in the embodiments of this application;

[0027] Figure 9 The constrained transmission signal diagram provided for the embodiments of this application;

[0028] Figure 10 This is a diagram of the second type of received signal after matched filtering provided in an embodiment of this application;

[0029] Figure 11 This application provides a second type of array element phase relationship diagram in its embodiments.

[0030] Figure 12 This application provides a second type of DBF pattern in its embodiments.

[0031] Figure 13 This is an enlarged view of the second type of DBF pattern provided in the embodiments of this application;

[0032] Figure 14 This is a schematic diagram of the structure of the orthogonal waveform generation device provided in the embodiments of this application;

[0033] Figure 15 This is a schematic diagram of the structure of a terminal device provided in an embodiment of this application. Detailed Implementation

[0034] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of this application with unnecessary detail.

[0035] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0036] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0037] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0038] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0039] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized. "A plurality" means "two or more."

[0040] Example 1

[0041] Embodiment 1 of this application provides an orthogonal waveform generation method, which can be executed by the processor of a terminal device when running a corresponding computer program. It is used to implement the constraint conditions for constructing each transmitted signal. The constraint conditions are used to make each transmitted signal orthogonal to the sum of all transmitted signals. Based on the constraint conditions, the transmitted signal is generated and radiated outward by the transmitting array element for target detection. The receiving array element receives the transmitted signal with target information, which enables the received signal received by the receiving array element to have a low range sidelobe after matched filtering.

[0042] like Figure 1 As shown, the orthogonal waveform generation method provided in this embodiment includes the following steps S11 to S14:

[0043] S11. Determine the number of transmitting elements, the number of receiving elements, and the length of the coding sequence of the antenna array.

[0044] In applications, the aforementioned antenna array can be a MIMO (multiple-in multiple-out) array, such as... Figure 2 Taking the MIMO array shown as an example, this MIMO array has two transmitting elements TX1 and TX2, and K receiving elements RX1, RX2, ..., RXK. The coding sequence length is N. Each transmitting element can transmit signals outward to radiate for target detection, and the receiving elements receive the transmitted signals containing target information. Each receiving element can simultaneously receive signals transmitted by all transmitting elements. Let the transmitted signal... Where L is the number of transmitted signals, which is 2 in this embodiment, x l (n) represents the l-th transmitted signal T. l The phase of (n). The transmitted signal is an orthogonal phase encoded waveform, when x l (n)∈{0,2π}, is called an orthogonal continuous phase encoded waveform.

[0045] S12. Based on the number of transmitting array elements and the length of the coding sequence, construct constraints for each transmitted signal. The constraints include an orthogonal constraint function, which is used to make each transmitted signal orthogonal to the sum of all transmitted signals.

[0046] In applications, the transmitted signal typically needs to meet the following two conditions:

[0047]

[0048]

[0049] The above A(T) l C(T,k) represents the aperiodic autocorrelation function of the l-th transmitted signal at time k. p ,Tq (k) represents the aperiodic cross-correlation function of the p-th and q-th transmitted signals at time k, such as Figure 3 As shown, except for the peak value A(T) l The non-periodic autocorrelation function values ​​other than 0) and all non-periodic cross-correlation function values ​​are collectively referred to as sidelobes. It can be seen that the ratio of main lobe to sidelobe reaches 19.89dB.

[0050] In practical applications, the received signal received by each receiving array element simultaneously contains the transmitted signals transmitted by both transmitting array elements TX1 and TX2. However, existing transmission signal generation processes only require that the above two conditions be met, and the aperiodic autocorrelation function only considers each transmitted signal T. l (n) is orthogonal to itself, therefore, after matched filtering of the received signal, it will have a high-range sidelobe, such as Figure 4 As shown, the ratio of the main lobe to the side lobe reaches 13.14 dB, which is not conducive to target detection and will cause false alarms or missed alarms for small targets or false alarms for the side lobe.

[0051] To address this issue, constraints can be incorporated into the signal generation process, and these constraints can include orthogonal constraint functions. Specifically, these orthogonal constraint functions are used to ensure that each transmitted signal T... l (n) and the sum of all transmitted signals Orthogonality facilitates the separation of the L transmitted signals during matched filtering, resulting in a lower range sidelobe in the received signal after matched filtering.

[0052] S13. Generate the transmission signal based on the constraints, and use the transmission array element to radiate outwards for target detection, and use the receiving array element to receive the transmission signal with target information.

[0053] In application, after the constraints are constructed in step S12, the transmission signal corresponding to each transmitting element can be generated using these constraints. Each transmission signal is constrained, and the transmitting elements radiate outwards to detect targets. The target reflects the transmission signal to the receiving element, which then receives the transmission signal carrying target information. For example... Figure 2 As shown, transmitting element TX1 radiates a constrained transmission signal T1 outward for target detection, and receiving elements RX1, RX2, ..., RXK receive T1 containing target information. Transmitting element TX2 radiates a constrained transmission signal T2 outward for target detection, and receiving elements RX1, RX2, ..., RXK receive T2 containing target information.

[0054] S14. Perform matched filtering on the received signal received by the receiving array element, perform digital beamforming based on the matched filtered received signal, and then perform target detection and output target information.

[0055] In the application, each receiving array element will simultaneously receive T1 and T2 containing target information. The received signal received by receiving array element RX1 can be represented as s1, the received signal received by receiving array element RX2 can be represented as s2, and the received signal received by receiving array element RXK can be represented as s... K s1, s2 and s K Both T1 and T2 are included, therefore, before performing Digital Beam Forming (DBF), matched filtering needs to be applied to the received signal to separate T1 and T2. For example... Figure 2 As shown, the received signal y after matched filtering is obtained. 1,1 y 1,2 ... y 1,K and y 2,1 y 2,2 ... y 2,K Then, digital beamforming can be performed based on these matched-filtered received signals, followed by target detection and output of target information.

[0056] The orthogonal waveform generation method provided in this application constructs constraints for each transmitted signal, which are used to make each transmitted signal orthogonal to the sum of all transmitted signals. Based on the constraints, the transmitted signal is generated and the transmitted signal is radiated outward by the transmitting array element to detect the target. The receiving array element receives the transmitted signal with target information, which enables the received signal received by the receiving array element to have a low range sidelobe after matched filtering.

[0057] Example 2

[0058] Embodiment 2 of this application provides an orthogonal waveform generation method based on Embodiment 1, which can be executed by the processor of a terminal device when running a corresponding computer program.

[0059] In one embodiment, step S12 includes: constructing an aperiodic correlation function for each transmitted signal and the sum of all transmitted signals based on the number of transmitted array elements and the length of the encoded sequence, and using the aperiodic correlation function as the orthogonal constraint function.

[0060] In applications, since each receiving array element receives L transmitted signals simultaneously, matched filtering needs to consider that each transmitted signal is orthogonal to the sum of all transmitted signals in order to separate the L transmitted signals during matched filtering. Therefore, the aperiodic autocorrelation function of the l-th transmitted signal at time k can be improved. Based on the number of transmitting array elements and the length of the encoded sequence, the aperiodic autocorrelation function of each transmitted signal to the sum of all transmitted signals is constructed as follows:

[0061]

[0062] The above B(T) l Let ,k) represent the aperiodic correlation function of the l-th transmitted signal at time k and the sum of all L transmitted signals. This aperiodic correlation function can be used as the orthogonal constraint function for the l-th transmitted signal. This orthogonal constraint function can be added during the signal generation process to ensure that each transmitted signal T... l (n) and the sum of all transmitted signals Orthogonality facilitates the separation of the L transmitted signals during matched filtering, resulting in a lower range sidelobe in the received signal after matched filtering.

[0063] In one embodiment, the constraint condition further includes a phase constraint condition, which is used to ensure that the phases of the receiving array elements are in an arithmetic progression relationship. Step S12 further includes: constructing an aperiodic cross-correlation function of the transmitted signal based on the number of transmitting array elements and the length of the encoded sequence; and constructing a phase constraint condition for each transmitted signal based on the aperiodic cross-correlation function and the orthogonal constraint function of each transmitted signal. Specifically, the main lobe peak value of the aperiodic cross-correlation function and the main lobe peak value of the orthogonal constraint function of each transmitted signal are calculated respectively; and the phase constraint condition for each transmitted signal is constructed based on the main lobe peak value of the aperiodic cross-correlation function, the main lobe peak value of the orthogonal constraint function of each transmitted signal, and a preset threshold.

[0064] In applications, assuming the number of receiving elements K is 20, this MIMO array can be equivalent to a conventional array consisting of 1 transmitting element and 40 receiving elements, such as... Figure 5 As shown. The receiving array consists of K equidistant receiving elements, with a spacing of d between adjacent elements. Considering a far-field narrowband signal incident on the spatial array, with receiving element RX1 as the reference, the phase difference between receiving element RX2 and receiving element RX1 is... Where λ represents the wavelength of the transmitted signal, and θ represents the azimuth angle of the transmitted signal. Similarly, the phase difference matrix of the K receiving elements can be obtained:

[0065]

[0066] The prerequisite for DBF is that the phase difference of the receiving array elements caused by the propagation path difference due to different spatial locations. The relationship is linear. Figure 6 The diagram shows the phase difference relationship of the 40 equivalent receiver elements during digital beamforming (DBF). Under normal DBF, the phase difference should be linear, as indicated by the asterisks in the figure. However, in the current DBF process, the phase difference of the equivalent receiver elements is non-linear, with a phase step after the 21st equivalent receiver element. This will cause the DBF pattern sidelobes to rise, as shown in the diagram. Figure 7 As shown, and the pointing offset, as Figure 8 As shown. To address this deficiency, considering that after matched filtering, the result is the sum of the autocorrelation of one signal and its cross-correlation with the other signals, and that the latter is a redundant term, its presence affects the linear phase relationship between array elements, thus leading to increased sidelobes and pointing offset in the DBF pattern. To eliminate their influence, phase constraint conditions can be added to minimize the cross-correlation result. The phase constraint condition for the l-th transmitted signal can be expressed as follows: Where D(dB) represents the preset threshold, which typically ranges from -50 to -35, |C(T) p ,T q ,0)| represents the main lobe peak value of the aperiodic cross-correlation function, min|B(T l ,0)| represents the main lobe peak value of the orthogonal constraint function of the l-th transmitted signal. The derivation of this phase constraint condition is as follows:

[0067] Based on the array distribution, a mathematical model is performed, and the l-th transmitted signal received by the k-th receiving element is: Among them, T l (t) represents the l-th transmitted signal; R is the radial distance to the target; ω0 = 2πf0, f0 is the frequency of the transmitted signal, and λ is the wavelength of the transmitted signal; v is the target velocity; t = (0:NN-1) / f s f s t represents the sampling frequency, and N represents the number of sampling points; m =mT r T r Let be the pulse repetition period, m be the number of pulses, m = (0:M-1); d be the spacing between receiving array elements, and θ be the azimuth angle. Then the received signal received by the k-th receiving array element is:

[0068]

[0069] The pulse compression coefficient when the received signal is matched and filtered is h l =(T l (-t)) * Then, the transmitted signal is separated by matched filtering to achieve MIMO full array recovery:

[0070]

[0071] in, This represents convolution. After matched filtering, the 40 equivalent receiving array elements of the equivalent array are recovered, and the received signal y after matched filtering of the first 20 equivalent receiving array elements is obtained. 1,k(n) corresponds to the transmit array element TX1, and the received signal y after matched filtering of the last 20 equivalent receive array elements. 2,k (n) corresponds to the transmitting element TX2. To perform DBF, the phases of the 40 equivalent receiving elements at the target location t = τ0 must be in an arithmetic progression, where τ0 represents the time delay and corresponds to the distance.

[0072]

[0073] Substituting t = τ0 into the above equation, we obtain the phase difference between the first 20 equivalent receiving array elements and the first equivalent receiving array element as follows:

[0074]

[0075] Similarly, the phase difference between the last 20 equivalent receiving array elements and the first equivalent receiving array element is:

[0076]

[0077] In summary:

[0078]

[0079] From the above formula, we can see that Subject to R 21 (τ0), R 22 (τ0), R 11 (τ0), R 12 The influence of (τ0) and orientation, i.e., the autocorrelation and cross-correlation of the target's velocity v, T1(t), and T2(t), R 21 (τ0) and R 12 (τ0) are redundant terms, and their residues disrupt the phase linearity relationship, affecting DBF synthesis. Therefore, in order to eliminate R 21 (τ0) and R 12 The effect of (τ0) on the phase requires reducing R. 21 (τ0) and R 12 (τ0) corresponds to the Nth point of cross-correlation, k = 0, which means that R is required to be... 12 (τ0)< <R 22 (τ0), and R 21 (τ0)< <R 11 (τ0). Therefore, a phase constraint condition is added during the generation of the transmitted signal. Updated to:

[0080]

[0081] Thus, the phases of these 40 equivalent receiving array elements are in an equal arithmetic relationship, enabling normal digital beamforming and avoiding sidelobe elevation and pointing offset in the DBF pattern.

[0082] In one embodiment, step S13 includes: generating the transmitted signal based on the orthogonal constraint function and the phase constraint condition, and radiating it outward through the transmitting array element for target detection; and receiving the transmitted signal carrying target information through the receiving array element. Step S14 includes: performing matched filtering on the received signal received by the receiving array element with each transmitted signal to obtain a matched-filtered received signal corresponding to each transmitted signal; performing digital beamforming based on the matched-filtered received signal corresponding to each transmitted signal; and then performing target detection and outputting target information.

[0083] In the application, after constructing the orthogonal constraint function and phase constraint condition for each transmitted signal, the corresponding transmitted signal can be generated based on these conditions. Each transmitted signal is then constrained, and the signal is radiated outwards by the transmitting array elements for target detection. The target reflects the transmitted signal to the receiving array elements, which then receive the transmitted signal carrying target information. After receiving the signal, the receiving array elements perform matched filtering with each transmitted signal to obtain the matched-filtered received signal for each transmitted signal.

[0084] like Figure 2 As shown, the received signal s1 received by the receiving array element RX1 is matched and filtered with the transmitted signal T1 through the matched filter h1 to obtain the matched filtered received signal y corresponding to the transmitted signal T1. 1,1 The received signal y is obtained by performing matched filtering between the transmitted signal T2 and the matched filter h2. 2,1 The received signal s2 received by the receiving array element RX2 is matched and filtered with the transmitted signal T1 through the matched filter h1 to obtain the matched filtered received signal y corresponding to the transmitted signal T1. 1,2 The received signal y is obtained by performing matched filtering between the transmitted signal T2 and the matched filter h2. 2,2 The received signal s received by the receiving array element RXK K The received signal y is obtained by performing matched filtering between the transmitted signal T1 and the matched filter h1. 1，K The received signal y is obtained by performing matched filtering between the transmitted signal T2 and the matched filter h2. 2，K .

[0085] After obtaining the matched-filtered received signal corresponding to each transmitted signal, digital beamforming can be performed normally based on the matched-filtered received signal corresponding to each transmitted signal, then target detection can be performed and target information can be output. The DBF pattern can avoid sidelobe elevation and pointing offset.

[0086] The orthogonal waveform generation method provided in this embodiment can adopt the peak sidelobe level minimization criterion and apply sequential quadratic programming to establish a mathematical model:

[0087]

[0088]

[0089] in,

[0090] F1(x)=|B(T l ,k)|,k=-N+1,…,-1,1,…,N-1,l=1,2,…,L

[0091] F2(x)=|C(T p T q ,k)|,k=-N+1,…,N-1,p≠q=1,2,…,L

[0092] F1(x) is the sidelobe value of the orthogonal constraint function B(Tl,k), and F2(x) is the aperiodic cross-correlation function C(Tl,k). p T q The sidelobe values ​​of (k), the model The purpose is to minimize the maximum sidelobe. This model can be solved using MATLAB's built-in constrained optimization function, fminimax. The model for fminimax is as follows:

[0093]

[0094] Set the variables according to Table 1, and call [x] = fminimax(@fun, x0, [], [], [], [], 1b, ub, @fun2, []) to obtain the required orthogonal coding phase x. Perform multiple experiments using MATLAB, and select the one with the largest main-sidelobe ratio.

[0095]

[0096] Table 1. Comparison between mathematical models and fminimax parameters

[0097] The orthogonal waveform generation method provided in this application constructs orthogonal constraint functions and phase constraint conditions for each transmitted signal, and generates corresponding transmitted signals based on these constraints. By constraining each transmitted signal, the method ensures that the received signal, after matched filtering, has low range sidelobes and can perform normal digital beamforming, avoiding sidelobe elevation and pointing offset in the DBF pattern. Figure 9 As shown, according to the mathematical model provided in this embodiment, D is set to -35, generating two constrained transmit signals of length 40, resulting in a set of orthogonal phase-coded waveforms with an orthogonality of 17.48dB. Figure 10 As shown, after matched filtering, the main lobe to side lobe ratio is 17.48 dB, compared to... Figure 4 This represents a 4dB improvement, which is beneficial for subsequent target detection. For example... Figure 11 As shown, the element phase difference is the same as that of a conventional array, and... Figure 6 Compared to the disappearance of a step jump. For example... Figure 12 and Figure 13 As shown, the DBF pattern no longer exhibits sidelobe elevation and pointing offset.

[0098] Example 3

[0099] like Figure 14 As shown, this embodiment also provides an orthogonal waveform generation device, the orthogonal waveform generation device 140 including:

[0100] Information determination module 141 is used to determine the number of transmitting elements, the number of receiving elements, and the length of the coding sequence of the antenna array;

[0101] The signal constraint module 142 is used to construct constraint conditions for each transmitted signal according to the number of transmitted array elements and the length of the encoded sequence. The constraint conditions include an orthogonal constraint function, which is used to make each transmitted signal orthogonal to the sum of all transmitted signals.

[0102] The signal transmitting module 143 is used to generate the transmitting signal based on the constraints, and to perform target detection by radiating it outward through the transmitting array element, and to receive the transmitting signal with target information through the receiving array element.

[0103] The waveform generation module 144 is used to perform matched filtering on the received signal received by the receiving array element, perform digital beamforming based on the matched filtered received signal, perform target detection, and output target information.

[0104] Optionally, the signal constraint module 142 is specifically used to construct an aperiodic correlation function of each transmitted signal and the sum of all transmitted signals according to the number of transmitted array elements and the length of the coding sequence, and use the aperiodic correlation function as the orthogonal constraint function.

[0105] Optionally, the signal constraint module 142 includes:

[0106] A cross-correlation construction unit is used to construct an aperiodic cross-correlation function of the transmitted signal based on the number of transmit array elements and the length of the encoded sequence;

[0107] The phase constraint unit is used to construct the phase constraint conditions for each transmitted signal based on the aperiodic cross-correlation function and the orthogonal constraint function for each transmitted signal.

[0108] Optionally, the phase constraint unit includes:

[0109] The peak calculation unit is used to calculate the main lobe peak value of the aperiodic cross-correlation function and the main lobe peak value of the orthogonal constraint function of each transmitted signal, respectively.

[0110] The constraint construction unit is used to construct phase constraint conditions for each transmitted signal based on the main lobe peak value of the aperiodic cross-correlation function, the main lobe peak value of the orthogonal constraint function of each transmitted signal, and a preset threshold.

[0111] Optionally, the signal transmitting module 143 is specifically used to generate the transmitting signal based on the orthogonal constraint function and the phase constraint condition, and to perform target detection by radiating it outward through the transmitting array element, and to receive the transmitting signal with target information through the receiving array element.

[0112] Optionally, the waveform generation module 144 includes:

[0113] The signal filtering unit is used to perform matched filtering on the received signal received by the receiving array element and each transmitted signal respectively to obtain the matched filtered received signal corresponding to each transmitted signal;

[0114] The waveform generation unit is used to perform digital beamforming based on the matched-filtered received signal corresponding to each transmitted signal, then perform target detection and output target information.

[0115] It should be noted that the information interaction and execution process between the above-mentioned devices / units are based on the same concept as the method embodiments of this application. For details on their specific functions and technical effects, please refer to the method embodiments section, and they will not be repeated here.

[0116] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0117] This application embodiment also provides a terminal device 150, such as Figure 15 As shown, it includes a memory 151, a processor 152, and a computer program 153 stored in the memory 151 and executable on the processor 152. When the processor 152 executes the computer program 153, it implements the steps of the orthogonal waveform generation method provided in the first aspect.

[0118] In applications, terminal devices may include, but are not limited to, processors and memory. Figure 15 This is merely an example of a terminal device and does not constitute a limitation on the terminal device. It may include more or fewer components than illustrated, or a combination of certain components, or different components, such as input / output devices, network access devices, etc. Input / output devices may include cameras, audio capture / playback devices, displays, etc. Network access devices may include network modules for wireless network communication with external devices.

[0119] In applications, the processor can be a Central Processing Unit (CPU), but it can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

[0120] In applications, the memory may be an internal storage unit of the terminal device in some embodiments, such as the hard drive or RAM of the terminal device. In other embodiments, the memory may be an external storage device of the terminal device, such as a plug-in hard drive, Smart Media Card (SMC), Secure Digital (SD) card, or Flash Card. The memory may also include both internal and external storage units of the terminal device. The memory is used to store the operating system, applications, boot loader, data, and other programs, such as the program code of computer programs. The memory can also be used to temporarily store data that has been output or will be output.

[0121] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, can implement the steps in the above-described method embodiments.

[0122] This application implements all or part of the processes in the methods of the above embodiments, which can be accomplished by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable medium can include at least: any entity or device capable of carrying the computer program code to a terminal device, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, such as a USB flash drive, a portable hard drive, a magnetic disk, or an optical disk.

[0123] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0124] Those skilled in the art will recognize that the device and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and generation constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0125] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interface, or the device may be indirectly coupled or communicated, and may be electrical, mechanical, or other forms.

[0126] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for generating orthogonal waveforms, characterized in that, include: Determine the number of transmitting elements, the number of receiving elements, and the length of the encoded sequence for the antenna array; Based on the number of transmitting array elements and the length of the coding sequence, constraints are constructed for each transmitted signal. The constraints include an orthogonal constraint function, which is used to make each transmitted signal orthogonal to the sum of all transmitted signals, thereby separating multiple transmitted signals during matched filtering. The transmitted signal is generated based on the constraints and is radiated outward by the transmitting array element to detect the target. The receiving array element receives the transmitted signal carrying the target information. The received signal received by the receiving array element is subjected to matched filtering, and digital beamforming is performed based on the matched filtered received signal. Then, target detection is performed and target information is output. The step of constructing constraints for each transmitted signal based on the number of transmitting array elements and the length of the encoded sequence includes: Based on the number of transmitting array elements and the length of the coding sequence, an aperiodic correlation function is constructed for each transmitted signal and the sum of all transmitted signals, and the aperiodic correlation function is used as the orthogonal constraint function.

2. The orthogonal waveform generation method as described in claim 1, characterized in that, The constraints also include phase constraints, which are used to ensure that the phases of the receiving array elements are in an arithmetic progression relationship.

3. The orthogonal waveform generation method as described in claim 1, characterized in that, The step of constructing constraints for each transmitted signal based on the number of transmitting array elements and the length of the encoded sequence further includes: Based on the number of transmitting array elements and the length of the encoded sequence, an aperiodic cross-correlation function of the transmitted signal is constructed; Based on the aperiodic cross-correlation function and the orthogonal constraint function of each transmitted signal, phase constraint conditions are constructed for each transmitted signal.

4. The orthogonal waveform generation method as described in claim 3, characterized in that, The step of constructing phase constraint conditions for each transmitted signal based on the aperiodic cross-correlation function and the orthogonal constraint function for each transmitted signal includes: Calculate the main lobe peak value of the aperiodic cross-correlation function and the main lobe peak value of the orthogonal constraint function for each transmitted signal; Based on the main lobe peak value of the aperiodic cross-correlation function, the main lobe peak value of the orthogonal constraint function of each transmitted signal, and a preset threshold, phase constraint conditions for each transmitted signal are constructed respectively.

5. The orthogonal waveform generation method as described in claim 2, characterized in that, The process of generating the transmitted signal based on the constraints and radiating it outward through the transmitting array elements for target detection, and receiving the transmitted signal carrying target information through the receiving array elements, includes: The transmitted signal is generated based on the orthogonal constraint function and the phase constraint condition, and is used for target detection by outward radiation through the transmitting array element, while the receiving array element receives the transmitted signal carrying target information.

6. The orthogonal waveform generation method according to any one of claims 1 to 5, characterized in that, The process of performing matched filtering on the received signal received by the receiving array element, performing digital beamforming based on the matched-filtered received signal, and then performing target detection and outputting target information includes: The received signal received by the receiving array element is matched and filtered with each transmitted signal to obtain the matched and filtered received signal corresponding to each transmitted signal. Digital beamforming is performed on the received signal after matched filtering for each transmitted signal, followed by target detection and output of target information.

7. An orthogonal waveform generation device, characterized in that, include: The information determination module is used to determine the number of transmitting elements, the number of receiving elements, and the length of the encoded sequence of the antenna array; The signal constraint module is used to construct constraint conditions for each transmitted signal according to the number of transmitted array elements and the length of the encoded sequence. The constraint conditions include an orthogonal constraint function, which is used to make each transmitted signal orthogonal to the sum of all transmitted signals, so as to separate multiple transmitted signals during matched filtering. The signal transmitting module is used to generate the transmitting signal based on the constraints, and to perform target detection by radiating it outward through the transmitting array element, and the receiving array element receives the transmitting signal with target information. The waveform generation module is used to perform matched filtering on the received signal received by the receiving array element, and to perform digital beamforming based on the matched filtered received signal, and then perform target detection and output target information. The signal constraint module is specifically used to construct an aperiodic correlation function between each transmitted signal and the sum of all transmitted signals based on the number of transmitted array elements and the length of the encoded sequence, and to use the aperiodic correlation function as the orthogonal constraint function.

8. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the orthogonal waveform generation method as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the orthogonal waveform generation method as described in any one of claims 1 to 6.

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