Target detection method, signal processing method, and integrated circuit

Abstract

The application relates to the technical field of radio communication and discloses a target detection method. The method comprises: dividing a Doppler spectrum into N sub-bands, the energy of N signals being extracted from the Doppler spectrum; among the N signals, traversing all possible position sequences of signals corresponding to a plurality of transmission antennas; on the basis of the total energy of the signals corresponding to the plurality of transmitting antennas under each position sequence, determining the sub-band to which the signal corresponding to each transmission antenna belongs. By traversing all possible position sequences of the signals of all the transmission antennas, the position sequence corresponding to the largest total energy can be used to determine the position of the signal of each transmission antenna in the sub-band, ensuring the accuracy of the channel separation of each transmission antenna and thereby increasing target detection accuracy. Further disclosed are a signal processing method, a computer-readable storage medium, an integrated circuit, a radio device, and a terminal device.

Description

Target detection method, signal processing method and integrated circuit CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on the Chinese patent application with application number "CN202311449163.3" and application date of November 1, 2023, and claims the priority of the above-mentioned Chinese patent application. The entire content of the above-mentioned Chinese patent application is hereby incorporated into this application by introduction. Technical Field

[0002] The embodiments of the present application relate to the field of radio technology, and in particular to a target detection method, a signal processing method, and an integrated circuit. Background Art

[0003] Frequency Modulated Continuous Wave (FMCW) radar generally transmits a detection signal with a linear swept frequency pulse waveform and receives an echo signal formed by the detection signal scattered and / or reflected by the target. This echo signal is mixed with the local oscillator (LO) output signal to obtain an intermediate frequency (IF) signal. After analog-to-digital conversion and sampling, the IF signal is coherently processed to achieve target detection and measurement of target parameters such as distance, speed, and angle.

[0004] Currently, mainstream millimeter-wave radar transmission waveforms include TDM (Time Division Multiplexing) MIMO (Multiple Input Multiple Output) and DDM (Doppler Division Multiplexing) MIMO. In DDM mode, multiple transmitting antennas can transmit simultaneously, achieving higher transmission gain than TDM. However, how to accurately separate the transmission channels in DDM mode remains a challenge. Summary of the Invention

[0005] The purpose of the embodiments of the present application is to provide a target detection method, a signal processing method and an integrated circuit, so that the transmission channels in the DDM mode can be accurately separated, thereby improving the accuracy of target detection.

[0006] To solve the above technical problems, an embodiment of the present application provides a target detection method, including: performing FFT in the range dimension and Doppler dimension on the echo signal respectively to obtain a Doppler spectrum under the same range gate; extracting the energy of N signals from the Doppler spectrum; wherein the Doppler spectrum is divided into N sub-bands, and the N signals belong to the N sub-bands; obtaining the energy sum of the signals corresponding to the multiple transmitting antennas in each position sequence, and obtaining the signals corresponding to each transmitting antenna in the N signals according to the position sequence with the largest energy sum; obtaining the parameters of the target based on the signal energy in each signal sub-band; wherein the signal sub-band is the sub-band to which the signals corresponding to each transmitting antenna belong.

[0007] An embodiment of the present application also provides a target detection method, including: performing FFT in the range dimension and Doppler dimension on the echo signal respectively to obtain a Doppler spectrum under the same range gate, and dividing the Doppler spectrum into N sub-bands to determine each signal sub-band, wherein the signal sub-band is the sub-band to which the signal corresponding to each transmitting antenna belongs; determining a target to be confirmed based on the signal energy in each signal sub-band; obtaining a first confidence level of the target to be confirmed, the first confidence level being used to characterize the difference between the sum of a first energy of the target to be confirmed and the sum of a second energy of the target to be confirmed, wherein the sum of the first energy represents the energy sum of the signal energy of the target to be confirmed in each signal sub-band, and the sum of the second energy represents the energy sum of the first energy sum and the signal energy of the target to be confirmed in at least one leakage sub-band, and the leakage sub-band is the remaining sub-bands of the N sub-bands except the signal sub-bands; deciding whether the target to be confirmed is a false target based on the first confidence level; and obtaining target parameters of the target to be confirmed if it is determined that the target to be confirmed is not a false target.

[0008] An embodiment of the present application also provides a target detection method, including: performing FFT in the range dimension and Doppler dimension on the echo signal respectively to obtain a Doppler spectrum under the same range gate, and dividing the Doppler spectrum into N sub-bands to determine each signal sub-band, wherein the signal sub-band is the sub-band to which the signal corresponding to each transmitting antenna belongs; determining a target to be confirmed based on the signal energy in each signal sub-band; obtaining a second confidence level of the target to be confirmed, the second confidence level being used to characterize the difference between a first energy value of the target to be confirmed and a second energy value of the target to be confirmed, wherein the first energy value represents the minimum energy value of the target to be confirmed in each signal sub-band, and the second energy value represents the maximum energy value of the target to be confirmed in a leakage sub-band; wherein the leakage sub-band is the remaining sub-bands in the N sub-bands except the signal sub-bands; deciding whether the target to be confirmed is a false target based on the second confidence level; and obtaining target parameters of the target to be confirmed if it is determined that the target to be confirmed is not a false target.

[0009] An embodiment of the present application also provides a signal processing method, comprising: performing spectral analysis on an echo signal to obtain a two-dimensional range Doppler spectrum; for any target data spectrum in the two-dimensional range Doppler spectrum, dividing the spectrum into N sub-bands along the Doppler dimension based on the minimum step phase of the signal transmitted by each transmitting antenna; determining the signal sub-bands in the N sub-bands based on the phase stepping rule of the signal transmitted by each transmitting antenna and the energy sum of each signal sub-band combination, and / or determining the order of signal sub-bands corresponding to the signal transmitted by each transmitting antenna; wherein the signal sub-band is a sub-band containing a target peak signal.

[0010] An embodiment of the present application further provides a computer-readable storage medium storing a computer program, which implements the above-mentioned target detection method when executed by a processor.

[0011] An embodiment of the present application also provides an integrated circuit, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the above-mentioned method.

[0012] An embodiment of the present application also provides a radio device, comprising: a carrier; an integrated circuit such as the above, arranged on the carrier; an antenna, arranged on the carrier, or the antenna and the integrated circuit are integrated into a single device and arranged on the carrier; wherein the integrated circuit is connected to the antenna for transmitting the target detection signal and / or receiving the echo signal.

[0013] An embodiment of the present application also provides a terminal device, comprising: a device body; and a radio device as described above, which is arranged on the device body; wherein the radio device is used for target detection to provide reference information for the operation of the device body.

[0014] In this embodiment of the present application, the Doppler spectrum is divided into N subbands, the energy of N signals is extracted from the Doppler spectrum, and all possible positional sequences of the signals corresponding to multiple transmit antennas within the N signals are traversed. Based on the energy sums of the signals corresponding to the multiple transmit antennas at each positional sequence, the subband to which the signals corresponding to each transmit antenna belong is determined. Because the position of the signal of each transmit antenna within the subband is determined based on the positional sequence corresponding to the maximum energy sum after traversing all possible positional sequences of the signals of each transmit antenna, the accuracy of channel separation for each transmit antenna is ensured, thereby improving the accuracy of target detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] One or more embodiments are exemplarily described by the figures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments.

[0016] FIG1 is a flow chart of a target detection method according to an embodiment of the present application;

[0017] FIG2 is a schematic diagram of a DDM-MIMO waveform using non-uniform spacing according to an embodiment of the present application;

[0018] FIG3 is a schematic diagram of a Doppler spectrum under the same range gate according to an embodiment of the present application;

[0019] FIG4 is a flow chart of obtaining target parameters based on signal energy in each signal sub-band according to an embodiment of the present application;

[0020] FIG5 is a flow chart of another method for obtaining target parameters based on signal energy in each signal sub-band according to an embodiment of the present application;

[0021] FIG6 is a schematic diagram of a second confidence level according to an embodiment of the present application;

[0022] FIG7 is a second flow chart of a target detection method according to an embodiment of the present application;

[0023] FIG8 is a third flow chart of a target detection method according to an embodiment of the present application;

[0024] FIG9 is a flow chart of a signal processing method according to an embodiment of the present application;

[0025] FIG10 is a schematic diagram of the structure of an integrated circuit according to an embodiment of the present application. DETAILED DESCRIPTION

[0026] There are currently two main methods for separating transmit channels in DDM mode. One is the uniformly Doppler-spaced DDM-MIMO waveform. This method is not affected by leakage and does not have the problem of false alarm points caused by leakage. However, when the target radial velocity exceeds the maximum unambiguous velocity assigned to the transmitting antenna, the peak of the spectrum will appear in the spectrum part corresponding to the other transmitting antenna, resulting in incorrect channel separation.

[0027] Another technology is the non-uniformly spaced DDM-MIMO waveform. Different transmitting antennas have a fixed relative position relationship in the Doppler dimension. If the target radial velocity is large, the spectra of different transmitting antennas will overlap. Combined with the channel separation algorithm, the non-uniform DDM waveform can achieve channel separation.

[0028] This application proposes a target detection method applicable to non-uniformly spaced DDMs. By traversing all possible position sequences of the signals from each transmitting antenna, the position of each transmitting antenna's signal within the subband is determined based on the position sequence corresponding to the maximum energy sum. This ensures the accuracy of channel separation for each transmitting antenna, thereby improving target detection accuracy. Furthermore, the confidence level of the target to be confirmed can be used to determine false targets, further improving target detection accuracy.

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, each embodiment of the present application will be described in detail below with reference to the accompanying drawings. However, it will be understood by those skilled in the art that in each embodiment of the present application, many technical details are proposed to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can be implemented. The division of the following embodiments is for convenience of description and should not constitute any limitation on the specific implementation of the present application. The various embodiments can be combined and referenced with each other under the premise of no contradiction.

[0030] Those skilled in the art will understand that electromagnetic wave signals are divided into radio waves and light waves, radio waves are divided into short waves, medium waves, long waves and microwaves, and light waves are divided into ultraviolet rays, visible light and infrared rays. Among them, microwaves are further divided into centimeter waves and millimeter waves. Centimeter waves mainly include UWB (Ultra Wide Band, frequency band of 3.1GHz~10.6GHz) and 24GHz band, and millimeter waves mainly include 60GHz band and 77GHz band (or 77GHz band~81GHz band). Ultraviolet rays and visible light can be collectively referred to as lasers, including visible lasers and invisible lasers. The frequency range of lasers is mainly (3.846~7.895)*10^5Hz. The embodiments of the present application mainly relate to signal processing of centimeter waves, millimeter waves and laser frequency bands.

[0031] One embodiment of the present application relates to a target detection method that can be applied to radar chips, or to terminal devices, integrated circuits, and other components that need to obtain target parameters. The following describes the implementation details of the embodiment of the present application in detail. The following content is provided for ease of understanding and is not required for implementing this solution.

[0032] In some embodiments, a target detection method includes: performing FFT on an echo signal in both the range and Doppler dimensions to obtain a Doppler spectrum under the same range gate; extracting the energy of N signals from the Doppler spectrum; wherein the Doppler spectrum is divided into N subbands, and the N signals belong to the N subbands; obtaining the energy sum of the signals corresponding to multiple transmitting antennas in each position sequence, and obtaining the signal corresponding to each transmitting antenna in the N signals based on the position sequence with the largest energy sum; obtaining target parameters based on the signal energy in each signal subband; wherein the signal subband is the subband to which the signal corresponding to each transmitting antenna belongs. For ease of understanding, the following embodiments are mainly described using the example of obtaining N subbands by uniformly dividing the Doppler spectrum.

[0033] As shown in FIG1 , in step 101 , a probe signal is transmitted through multiple transmitting antennas in a Doppler dimension multiplexing (DDM) mode.

[0034] In one example, a radar system with four transmit antennas (4TX) and four receive antennas (4RX) simultaneously transmits detection signals using a non-uniformly spaced DDM-MIMO waveform. The transmit waveform is shown in Figure 2. The phase shift step for TX0 is 0°, the phase shift step for TX1 is 45° (i.e., π / 4), the phase shift step for TX2 is 180° (i.e., π), and the phase shift step for TX3 is 270° (i.e., 3π / 2). The echo signal received by each receive antenna includes the signals corresponding to all four transmit antennas. Since the phase shift step for each transmit antenna is fixed, the relative position of the signals corresponding to each transmit antenna in the echo signal is fixed.

[0035] In step 102, an FFT (Fast Fourier Transform) (i.e., 2D-FFT) is performed on the echo signal in both the range and Doppler dimensions to obtain a Doppler spectrum within the same range bin. Specifically, the echo signal received by the receiving antenna is mixed with the local oscillator signal output by the local oscillator to obtain an intermediate frequency (IF) signal. The resulting digital signal, obtained by analog-to-digital conversion of the IF signal, is then subjected to FFTs in both the range and Doppler dimensions to obtain a Doppler spectrum within the same range bin. The Doppler spectrum within the same range bin can be the data directly output from the 2D-FFT or the data output from a Constant False Alarm Rate (CFAR) detector. It should be noted that here, only the implementation of the 2D-FFT in step 102 by performing FFT in the range dimension and the Doppler dimension respectively is taken as an example. When applied, any other method that can obtain the Doppler spectrum under the same range gate can also be used to implement 2D-FFT. This has been recorded in the relevant technology and will not be repeated here.

[0036] In one example, the 2D-FFT result for a stationary target is shown in Figure 3. Figure 3 illustrates the Doppler spectrum under the same range gate, which is divided into N equally spaced subbands. N is determined by the minimum phase shift step among the multiple transmitting antennas relative to the reference transmitting antenna. Taking the aforementioned 4TX and 4RX radar system as an example, TX0 is the reference transmitting antenna. The phase shift step of TX1 relative to TX0 is 45°, the phase shift step of TX2 relative to TX0 is 180°, and the phase shift step of TX3 relative to TX0 is 270°. This means that the minimum phase shift step among the multiple transmitting antennas relative to the reference transmitting antenna is 45°, and there are eight 45° steps in 360°. Therefore, N is 8. (In this case, the Doppler spectrum is divided into eight equally spaced subbands, namely, Subband 0, Subband 1, Subband 2, Subband 3, Subband 4, Subband 5, Subband 6, and Subband 7, as delineated by two adjacent dashed lines in Figure 3.) In one example, if the minimum phase shift step of the multiple transmitting antennas relative to the reference transmitting antenna is 60°, then the value of N is 6, i.e., N is a positive integer. In another example, if the minimum phase step of the transmitted signal of each transmitting antenna is 30°, since 360° includes 12 60°, 12 sub-bands are divided along the Doppler dimension, i.e., N is 12. Of course, the above is only an example of the minimum phase step and the corresponding Doppler spectrum division in different situations. In some embodiments, the minimum phase step and the corresponding Doppler spectrum division can also be set differently according to actual needs and will not be described in detail here. It is worth mentioning that the radar system in this embodiment can be multi-transmit and multi-receive, or multi-transmit and one-receive, without limitation here, as long as the number of transmitting antennas is less than the number of divided sub-bands N. For ease of understanding, the following mainly uses the example of a minimum phase step of 45° and N=8 as an example.

[0037] In step 103, the energy of N signals is extracted from the Doppler spectrum; the N signals belong to N subbands, i.e., one signal is extracted from each subband, and the number of Doppler units between any two adjacent signals is the same. In one example, the N extracted signals include at least one peak. It should be noted that in the embodiments of the present application, after obtaining the Doppler spectrum under the same range gate, the processing performed on the Doppler spectrum is for the Doppler spectrum under the same range gate, not for the Doppler spectra under different range gates. This will not be further described here or later.

[0038] Specifically, taking N as 8 and a Doppler spectrum consisting of 256 Doppler bins as an example, after the Doppler spectrum is equally spaced into N subbands, each subband consists of 32 Doppler bins. A signal is extracted from each of the 8 subbands, and the number of Doppler bins between any two adjacent signals is the same. For example, if the Doppler bin value of the signal extracted in the first subband is 1, then the Doppler bin value of the signal extracted in the second subband is 1+32, the Doppler bin value of the signal extracted in the second subband is 1+32×2, the Doppler bin value of the signal extracted in the third subband is 1+32×3, and so on, ensuring that the number of Doppler bins between any two adjacent signals is the same.

[0039] In step 104, the antenna energy subband, or signal subband, is obtained. A signal subband is the subband to which the signal corresponding to each transmit antenna belongs. In this step, all possible positions of the signals corresponding to the multiple transmit antennas in the N signals are traversed, and the energy sum of the signals corresponding to the multiple transmit antennas in each position order is obtained. The signal corresponding to each transmit antenna in the N signals is then determined based on the position order with the largest energy sum.

[0040] In radar operation, the detected target's velocity may occur in any Doppler bin, meaning the position of TX0 may occur in any subband. Taking N as 8 in the above example, there are eight possible TX0 positions (i.e., the position in the Doppler spectrum of the signal corresponding to TX0). Since the relative positions of the signals corresponding to each transmitting antenna are fixed in the echo signal, if the position of TX0 is fixed, the positions of TX1, TX2, and TX3 are also fixed. As shown in Figure 3, when the signal corresponding to TX0 is in the 0th Doppler bin of the Doppler spectrum, the signal corresponding to TX1 is in the 32nd Doppler bin, the signal corresponding to TX2 is in the 128th Doppler bin, and the signal corresponding to TX3 is in the 192nd Doppler bin.

[0041] Therefore, when it is uncertain in which subband the signal corresponding to TX0 is located, all possible position orders of each TX are shown in Table 1.

[0042] Table 1: Different combinations of TX order

[0043]

[0044] The TX order in Table 1 indicates the subbands to which the signals corresponding to the four transmitting antennas belong. For example, in possibility 1, the signal corresponding to TX0 is in the first subband (subband 0), the signal corresponding to TX1 is in the second subband (subband 1), the signal corresponding to TX3 is in the fifth subband (subband 4), and the signal corresponding to TX3 is in the seventh subband (subband 6).

[0045] By cyclic shifting, we can traverse all possible position sequences of the signals corresponding to multiple transmit antennas in N subbands (as shown in Table 1) and obtain the energy sum of the signals corresponding to the multiple transmit antennas in each position sequence, that is, the energy sum under N TX sequences. Taking Table 1 as an example, the energy sum under 8 TX sequences is:

[0046] A0=S0+S1+S4+S6;

[0047] A1=S1+S2+S5+S7;

[0048] A2=S2+S3+S6+S0;

[0049] A3=S3+S4+S7+S1;

[0050] A4=S4+S5+S0+S2;

[0051] A5=S5+S6+S1+S3;

[0052] A6=S6+S7+S2+S4;

[0053] A7=S7+S0+S3+S5;

[0054] Among them, S0 represents the energy value of the signal located in the first subband (subband 0) among the 8 extracted signals, S1 represents the energy value of the signal located in the second subband (subband 1) among the 8 extracted signals, S2 represents the energy value of the signal located in the third subband (subband 2) among the 8 extracted signals, and so on.

[0055] Find the maximum value among [A0, A1, A2, A3, A4, A5, A6, A7]. For example, if A5 is the maximum value, then the subbands corresponding to the signals transmitted by TX0–TX3 are in the order [5, 6, 1, 3]. That is, the signal transmitted by TX0 belongs to subband 5, the signal transmitted by TX1 belongs to subband 6, the signal transmitted by TX2 belongs to subband 1, and the signal transmitted by TX3 belongs to subband 3.

[0056] That is, the signal corresponding to each transmitting antenna among the N signals is obtained in order of energy and maximum position, and then the signal subband, that is, the subband to which the signal corresponding to each transmitting antenna belongs, is determined.

[0057] In step 105, target detection is performed based on the signal energy in each antenna energy sub-band. That is, target parameters are obtained based on the signal energy in each signal sub-band, such as target speed, distance, angle and other information.

[0058] In one example, the specific process for obtaining target parameters based on the signal energy in each signal subband is shown in FIG4 . In step 401, a first confidence level (tx_order_conf1) of the target to be confirmed is obtained, where the first confidence level is used to characterize the difference between the sum of the first energy of the target to be confirmed and the sum of the second energy of the target to be confirmed. The first energy sum represents the energy sum of the signal energy of the target to be confirmed in each signal subband, and the second energy sum represents the energy sum of the first energy sum and the signal energy of the target to be confirmed in at least one leakage subband, where the leakage subband is the remaining subband of the N subbands excluding the signal subbands. In one example, the second energy sum may also be the sum of the first energy sum and the energy sum of all leakage subbands.

[0059] Since the energy of the same target can be detected in different subbands, the sum of the signal energies in each signal subband (the sum of the first energies) for a real target point should be close to or even equal to the sum of the first energy and the signal energy in at least one leakage subband. Therefore, the first confidence level can effectively determine whether the target is a false target.

[0060] In one example, the ratio of the sum of the first energy to the sum of the second energy can be directly obtained as the first confidence level of the target to be confirmed. Taking Table 1 above as an example, the sum of the first energy is max(A0, A1, A2, A3, A4, A5, A6, A7), and the sum of the second energy is but

[0061] In step 402, a decision is made based on the first confidence level whether the target to be confirmed is a false target.

[0062] In one example, when the first confidence level is the ratio of the sum of the first energy to the sum of the second energy, whether the target to be confirmed is a real target can be determined by whether the first confidence level is greater than a preset first threshold. If it is greater than the preset first threshold, it is determined to be a real target. Otherwise, it is not a real target, that is, a false target. The first threshold is an adjustable parameter and can be debugged according to actual data. For example, the first threshold TH tx_order_conf1It is set to 0.75. It can be understood that the larger the first threshold is set, the more accurate the false target judgment is, that is, the better the detection quality of the target to be confirmed is.

[0063] If it is determined that the target to be confirmed is not a false target, the process proceeds to step 403, where target parameters are acquired for the target to be confirmed. For example, distance, speed, and angle measurements are performed on the target to be confirmed. If it is determined that the target to be confirmed is a false target, the process proceeds to step 404, where the target to be confirmed is deleted.

[0064] In another example, the specific process for obtaining target parameters based on the signal energy in each signal subband is shown in Figure 5. In step 501, a second confidence level (tx_order_conf2) of the target to be confirmed is obtained. The second confidence level is used to represent the difference between a first energy value of the target to be confirmed and a second energy value of the target to be confirmed, where the first energy value represents the minimum energy value of the target to be confirmed in each signal subband, and the second energy value represents the maximum energy value of the target to be confirmed in a leakage subband; wherein the leakage subband is the remaining subbands of the N subbands excluding the signal subbands, as shown in Figure 6.

[0065] Since the energy of the same target to be confirmed can be detected in different sub-bands, and for a real target point, the energy value in the signal sub-band should be significantly greater than the energy value in the leakage sub-band, the second confidence level can be used to effectively determine whether the target to be confirmed is a false target.

[0066] In one example, the logarithm of the ratio of the first energy value to the second energy value can be obtained as the second confidence level of the target to be confirmed. The first energy value is defined as min(Ptx0, Ptx1, Ptx2, Ptx3), and the second energy value is defined as max(Plkg0, Plkg1, Plkg2, Plkg3), where Ptx0, Ptx1, Ptx2, and Ptx3 are the energy values ​​of the target to be confirmed in each signal subband (i.e., the energy values ​​in the subbands corresponding to the signals TX0 to TX3), and Plkg0, Plkg1, Plkg2, and Plkg3 are the energy values ​​of the target to be confirmed in the leakage subband.

[0067] In other examples, the ratio of the first energy value to the second energy value may be directly used as the second confidence level, which will not be enumerated here.

[0068] In step 502, a decision is made based on the second confidence level whether the target to be confirmed is a false target.

[0069] In one example, whether the target to be confirmed is a false target can be determined by checking whether the second confidence level is greater than a preset second threshold. If so, the target is determined to be a real target; otherwise, the target is not a real target, i.e., a false target. The second threshold is an adjustable parameter that can be adjusted based on actual data. For example, if the second confidence level is set to the logarithm of the ratio of the first energy value to the second energy value, the second threshold can be set to 3. It can be understood that the larger the second threshold, the more accurate the false target determination, i.e., the better the detection quality of the target to be confirmed.

[0070] If it is determined that the target to be confirmed is not a false target, the process proceeds to step 503, where target parameters are acquired for the target to be confirmed. For example, distance, speed, and angle measurements are performed on the target to be confirmed. If it is determined that the target to be confirmed is a false target, the process proceeds to step 504, where the target to be confirmed is deleted.

[0071] In some examples, the target parameters are acquired based on the signal energy in each signal subband in step 105. The target detection process shown in FIG4 or FIG5 can be used. That is, for a target to be confirmed, either the first confidence level or the second confidence level is used to determine whether the target is a false target. Alternatively, both the first confidence level and the second confidence level can be used to determine whether the target is a false target. That is, for a target to be confirmed, if tx_order_conf2>TH tx_order_conf2 And tx_order_conf2>TH tx_order_conf2 , then keep the target point; otherwise delete the target point.

[0072] In one example, the first confidence level can be used first to determine whether a target is a false target. If the target is not a false target, the second confidence level can be used to determine whether the target is a false target. In other words, if the first confidence level can determine that the target is a false target, the second confidence level does not need to be used to determine whether the target is a false target. If the first confidence level can determine that the target is not a false target, the second confidence level needs to be used to determine whether the target is a false target.

[0073] It can be understood that when the Doppler spectrum under the same range gate obtained in step 102 is data directly output after 2D-FFT, after determining each signal sub-band, parameters such as distance, speed, angle, etc. of the target can be obtained by adopting any target detection process as shown in Figure 4 or Figure 5. For example, after using the first confidence level and / or the second confidence level to judge the false target, subsequent DOA (Direction of Arrival) estimation and velocity deambiguation are performed according to the determined signal sub-band without performing CFAR.

[0074] In other examples, step 105 of acquiring the target parameters based on the signal energy in each signal sub-band may also not perform the false target judgment based on the first confidence level and / or the second confidence level, that is, directly determining the target to be confirmed based on the signal energy in each signal sub-band, and performing subsequent DOA estimation and velocity deambiguation based on the determined signal sub-band.

[0075] In other examples, after the target to be confirmed is determined based on the signal energy in each signal sub-band, deduplication processing can be performed on the determined target to be confirmed, and the target parameters of the target to be confirmed after deduplication processing can be obtained. For example, the energy value of the determined target to be confirmed is stored in a pre-created two-dimensional matrix, wherein the storage position of the energy value of the target to be confirmed in the two-dimensional matrix is ​​determined based on the distance dimension unit value of the target to be confirmed in the distance spectrum and the Doppler unit value of the target to be confirmed in the Doppler spectrum. For the energy value of each target to be confirmed stored in the two-dimensional matrix, it is detected whether the energy value of the target to be confirmed is greater than the energy value of the target to be confirmed stored at a nearby location. If it is less than the energy value of the target to be confirmed stored at a nearby location, the target to be confirmed is deleted as a duplicate target.

[0076] The size of the created two-dimensional matrix Pow_matrix is For example, Rng_nfft represents the number of FFT points in the distance dimension, Rng_nfft / 2 is based on the consideration that the FFT in the distance dimension is symmetrical, so only half of the data is meaningful; Vel_nfft represents the number of FFT points in the Doppler dimension, and Vel_nfft / 8 is based on the example of 8 preset sub-bands. The "8" here represents the number of preset sub-bands. The algorithm for deduplication of the determined target to be confirmed is as follows:

[0077] First, all values ​​of the two-dimensional matrix Pow_matrix are initialized to 0. This matrix is ​​used to store the energy results of the unambiguous Doppler unit peak.

[0078] Then, the Doppler unit defuzzification operation is performed on the target point that has completed the TX sequence determination: the Doppler unit value of the target to be confirmed is The remainder is taken as the ordinate position of the target to be confirmed in the two-dimensional matrix. This operation limits the Doppler unit of the target point to The energy of the target point is stored in Pow_matrix.

[0079] Finally, the energy of each target point in Pow_matrix is ​​determined. If the energy of the target point is greater than the energy of the four target points above, below, left, and right, the target to be confirmed is output for subsequent distance measurement, speed measurement, and angle measurement. Otherwise, the target to be confirmed is determined to be a duplicate target point and deleted.

[0080] By performing deduplication processing on the determined targets to be confirmed, some target points can be deleted to prevent the output of too many targets with repeated information.

[0081] In this embodiment, the Doppler spectrum is divided into N equally spaced subbands, the energy of N signals is extracted from the Doppler spectrum, and all possible positional sequences of the signals corresponding to multiple transmit antennas within the N signals are traversed. Based on the energy sums of the signals corresponding to the multiple transmit antennas at each positional sequence, the subband to which the signals corresponding to each transmit antenna belong is determined. Because all possible positional sequences of the signals from each transmit antenna are traversed and the position of the signals from each transmit antenna within the subband is determined based on the positional sequence corresponding to the maximum energy sum, the accuracy of channel separation for each transmit antenna is guaranteed, thereby improving target detection accuracy. This embodiment is applicable to any non-uniformly spaced DDM-MIMO scheme and has no restrictions on the number of transmit and receive antennas. For example, for MIMO schemes, it is applicable to DDM modes with any number of transmit and receive antennas. In other schemes, it is also applicable to schemes with at least one receive antenna and at least two transmit antennas.

[0082] In addition, for a target to be confirmed, the first confidence level and / or the second confidence level may be used to determine whether a target is a false target, thereby deleting the false target and retaining the true target, thereby further improving the accuracy of target detection.

[0083] In addition, the determined targets to be confirmed can be deduplicated to delete some target points to prevent the output of too many targets with repeated information.

[0084] Another embodiment of the present application relates to a target detection method, which can be applied to a radar chip, or a terminal device, integrated circuit, or other component that needs to obtain target parameters. In some embodiments, the target detection method includes: performing FFT in the range dimension and the Doppler dimension on the echo signal to obtain a Doppler spectrum under the same range gate, dividing the Doppler spectrum into N subbands, and determining each signal subband, wherein the signal subband is the subband to which the signal corresponding to each transmitting antenna belongs; determining a target to be confirmed based on the signal energy in each signal subband; obtaining a first confidence level for the target to be confirmed, wherein the first confidence level is used to characterize the difference between a sum of a first energy of the target to be confirmed and a sum of a second energy of the target to be confirmed, wherein the first energy sum represents the energy sum of the signal energy of the target to be confirmed in each signal subband, and the second energy sum represents the energy sum of the first energy sum and the signal energy of the target to be confirmed in at least one leakage subband, wherein the leakage subband is the remaining subbands of the N subbands excluding the signal subbands; determining whether the target to be confirmed is a false target based on the first confidence level; and obtaining target parameters for the target to be confirmed if it is determined that the target to be confirmed is not a false target. For ease of understanding, the following embodiments are mainly described by taking the example of uniformly dividing the Doppler spectrum to obtain N sub-bands.

[0085] In some embodiments, the specific process of the target detection method is shown in FIG7 .

[0086] In step 701, a plurality of transmitting antennas transmit a sounding signal in a Doppler dimension multiplexing (DDM) mode, wherein the sounding signals transmitted by the plurality of transmitting antennas are non-uniformly spaced DDM-MIMO waveforms. This step is similar to step 101 and will not be described in detail here.

[0087] In step 702, an FFT (i.e., 2D-FFT) is performed on the echo signal in both the range and Doppler dimensions to obtain a Doppler spectrum for the same range gate. The Doppler spectrum for the same range gate can be the data output after the 2D-FFT or the data output after the CFAR. This step is similar to step 102 and will not be repeated here.

[0088] In step 703, the Doppler spectrum is divided into N equally spaced subbands, and signal subbands are determined. A signal subband is a subband to which a signal corresponding to each transmit antenna belongs. In one example, the signal subbands can be determined through steps 103 and 104 in the above embodiment, and are not further described here.

[0089] In step 704, a first confidence level (tx_order_conf1) for the target to be confirmed is obtained. The first confidence level represents the difference between the sum of the first energy of the target to be confirmed and the sum of the second energy of the target to be confirmed. The first energy sum represents the sum of the signal energies of the target to be confirmed in each signal subband, and the second energy sum represents the sum of the first energy sum and the signal energy of the target to be confirmed in at least one leakage subband. This step is similar to step 401 and is not further described here.

[0090] In step 705, a decision is made based on the first confidence level whether the target to be confirmed is a false target. If the target to be confirmed is not a false target, the process proceeds to step 706, where target parameters are acquired for the target to be confirmed. If the target to be confirmed is a false target, the process proceeds to step 707, where the target to be confirmed is deleted. Steps 705 to 707 are similar to steps 402 to 404 and are not further described here.

[0091] In other examples, after determining the target to be confirmed based on the signal energy in each signal subband, a second confidence level of the target to be confirmed can be obtained, and based on the second confidence level, a decision is made as to whether the target to be confirmed is a false target, i.e., the operations of steps 501 to 502 are performed. That is, for a target to be confirmed, if tx_order_conf1>TH tx_order_conf1 And tx_order_conf2>TH tx_order_conf2 , then keep the target point; otherwise delete the target point.

[0092] In this embodiment, for a target to be confirmed, by using the first confidence level and / or the second confidence level to determine whether it is a false target, the false target can be deleted and the true target can be retained to ensure accurate identification of the true target, thereby improving the accuracy of target detection. In one example, the first confidence level can be used first to determine whether it is a false target. If it is determined that the target is not a false target, the second confidence level can be used to determine whether it is a false target.

[0093] Another embodiment of the present application relates to a target detection method, which can be applied to a radar chip, or a terminal device, integrated circuit, or other component that needs to obtain target parameters. In some embodiments, the target detection method includes: performing FFT in the range dimension and Doppler dimension on the echo signal to obtain a Doppler spectrum under the same range gate, dividing the Doppler spectrum into N sub-bands, and determining each signal sub-band, wherein the signal sub-band is the sub-band to which the signal corresponding to each transmitting antenna belongs; determining a target to be confirmed based on the signal energy in each signal sub-band; obtaining a second confidence level of the target to be confirmed, wherein the second confidence level is used to characterize the difference between a first energy value of the target to be confirmed and a second energy value of the target to be confirmed, wherein the first energy value represents the minimum energy value of the target to be confirmed in each signal sub-band, and the second energy value represents the maximum energy value of the target to be confirmed in a leakage sub-band; wherein the leakage sub-band is the remaining sub-bands of the N sub-bands except the signal sub-bands; determining whether the target to be confirmed is a false target based on the second confidence level; and obtaining target parameters for the target to be confirmed if it is determined that the target to be confirmed is not a false target. For ease of understanding, the following mainly uses an example of uniformly dividing the Doppler spectrum to obtain N sub-bands.

[0094] In some embodiments, the specific process of the target detection method is shown in FIG8 .

[0095] In step 801, a detection signal is transmitted in a Doppler dimension multiplexing (DDM) mode via multiple transmitting antennas, wherein the detection signals transmitted by the multiple transmitting antennas are non-uniformly spaced DDM-MIMO waveforms. This step is similar to step 101 and will not be repeated here.

[0096] In step 802, FFT (ie, 2D-FFT) is performed on the echo signal in the range dimension and the Doppler dimension to obtain the Doppler spectrum under the same range gate. This step is similar to step 102 and will not be repeated here.

[0097] In step 803, the Doppler spectrum is divided into N equally spaced subbands, and each antenna energy subband, i.e., a signal subband, is determined. A signal subband is a subband to which a signal corresponding to each transmit antenna belongs. In one example, each signal subband can be determined through steps 103 and 104 in the above embodiment, and will not be further described here.

[0098] In step 804, a second confidence level for the target to be confirmed is obtained. The second confidence level represents the difference between the first energy value of the target to be confirmed and the second energy value of the target to be confirmed. The first energy value represents the minimum energy value of the target to be confirmed in each signal subband, and the second energy value represents the maximum energy value of the target to be confirmed in the leakage subband. The leakage subband is the remaining subbands of the N subbands excluding the signal subbands. This step is similar to step 501 and is not further described here.

[0099] In step 805, a decision is made based on the second confidence level whether the target to be confirmed is a false target. If the target to be confirmed is not a false target, the process proceeds to step 806, where target parameters are acquired for the target to be confirmed. If the target to be confirmed is a false target, the process proceeds to step 807, where the target to be confirmed is deleted. Steps 805 to 807 are similar to steps 502 to 504 and are not further described here.

[0100] In this embodiment, for a target to be confirmed, by using the second confidence level to determine a false target, the false target can be deleted and the real target can be retained to ensure accurate identification of the real target, thereby improving the accuracy of target detection.

[0101] In an embodiment of the present application, a signal processing method is provided, which can be applied to a radar system with non-uniformly spaced DDM, wherein the antenna array of the radar system includes at least one receiving antenna and at least two transmitting antennas, for example, it can be applicable to an antenna array with multiple transmissions, or a radar system in a DDM-MIMO mode, etc., that is, after performing processing such as mixing, analog-to-digital conversion, and sampling on the received echo signal, a two-dimensional range-Doppler spectrum is obtained based on spectrum analysis processing such as range-dimensional FFT and velocity-dimensional FFT as data to be processed for subsequent operations, that is, the data to be processed can be the two-dimensional range-Doppler spectrum directly output after the above-mentioned spectrum analysis processing, or it can be the two-dimensional range-Doppler spectrum output after continuous constant false alarm processing (CFAR) based on the spectrum analysis result, and the two-dimensional range-Doppler spectrum contains multiple target data spectra.

[0102] For any of the target data spectra described above, the spectrum can be divided into N subbands along the Doppler dimension, to be further confirmed, based on factors such as the step phase value when the transmitting antenna transmits the signal. Furthermore, the subband division in the Doppler dimension can be uniform or non-uniform, as long as the target peaks (energy peaks) corresponding to the respective transmitting antennas are distributed in different subbands. For example, the subband division in the Doppler dimension can be performed based on the minimum step phase value when the transmitting antenna transmits the signal. For example, if the minimum step phase value is 45°, then N is 8 (360° / 45°=8), resulting in 8 or 16 subbands, i.e., any multiple of 8 is acceptable. Assume that there are 512 Doppler bins in the Doppler dimension. If the subbands are evenly divided into 8 subbands, the subbands are arranged sequentially along the Doppler dimension, and each subband contains 64 Doppler bins. If the subbands are unevenly divided into 8 subbands, the number of Doppler bins in each subband can be determined based on the stepped phase pattern used by each transmitting antenna when transmitting signals. For example, the first subband may contain 7 Doppler bins, the second subband may contain 9 Doppler bins, and the remaining subbands may each contain 8 Doppler bins. In short, various combinations are possible and can be set based on actual needs. The only requirement is to ensure that after the subband division, the target peaks (energy peaks) corresponding to each transmitting antenna are distributed in different unconfirmed subbands. That is, a unconfirmed subband may contain only the target peak corresponding to one transmitting antenna or may not contain the target peak corresponding to any transmitting antenna. For example, if the minimum phase step of the signal transmitted by each transmitting antenna is 30°, since 360° includes 12 60° sub-bands, 12 sub-bands are generated along the Doppler dimension, i.e., N is 12. Of course, the above is merely an example of the minimum phase step and the corresponding Doppler spectrum division in different situations. In some embodiments, the minimum phase step and the corresponding Doppler spectrum division may be specifically set according to actual needs and may differ from the above example, which will not be further described here.

[0103] Based on the N subbands divided above, the subbands containing the target peak signal can be determined based on the phase stepping pattern of the signals transmitted by each transmitting antenna, combined with the energy sum dimension of the signal subband combination. This means that the subbands containing the target peak signal can be identified and designated as signal subbands. Correspondingly, the remaining subbands can be designated as leakage subbands (also known as empty subbands). Furthermore, while confirming the signal subbands, the target peaks corresponding to each transmitting antenna in the target data spectrum can be ranked sequentially in the N subbands in the Doppler dimension, i.e., the order of the transmitting antennas in the target data spectrum can be obtained. In other embodiments, the steps of confirming the signal subbands and obtaining the order of the transmitting antennas in the target data spectrum can also be performed independently.

[0104] The corresponding order of transmitting antennas in the target data spectrum confirmed above can be used to remove adjacent repeated false targets, resolve velocity ambiguity, and / or estimate the direction of arrival, so as to achieve the purpose of improving the accuracy of target speed and angle measurement.

[0105] In some embodiments, based on the identified signal and leakage subbands, corresponding preset confidence levels are set based on the energy dimension to remove some false targets. For scenarios where the two-dimensional range-Doppler spectrum directly output after spectral analysis serves as the processed data, using the aforementioned confidence level to remove false targets can replace the constant false alarm (CFAR) operation in traditional signal processing to achieve corresponding false alarm processing. This can also be combined with CFAR to improve target detection accuracy.

[0106] For example, the preset confidence level can be obtained based on the signal subband energy and at least a portion of the leakage subband energy. For example, the preset confidence level may include a first confidence level and a second confidence level. The first confidence level may be the ratio of the energy sum of the signal subband to the energy sum of all subbands, and the second confidence level may be the ratio of the minimum signal subband peak to the maximum leakage subband peak. Simultaneously, false targets can be removed independently based on the first confidence level and the second confidence level, or they can be combined to determine false targets under the conditions that meet the preset judgment. The first confidence level may also be the ratio of the energy sum of all signal subbands to the energy sum of all signal subbands plus the energy of the preset leakage subband.

[0107] It should be noted that in the signal processing method of this embodiment, the specific implementation scheme can be implemented by those skilled in the art using the technical content described in the target detection method embodiment of this application, provided that no conflict occurs. It will not be described here in detail, but its specific implementation technical content should also be included in the technical scheme in the signal processing method embodiment of this application.

[0108] The above-described signal processing method can be applied to radar chips, or to components such as terminal devices and integrated circuits that require acquisition of target parameters. In some embodiments, the signal processing method is applied to a radar system, wherein the antenna array of the radar system includes at least one receiving antenna and at least two transmitting antennas. The method includes: performing spectral analysis on the echo signal to obtain a two-dimensional range-Doppler spectrum; for any target data spectrum in the two-dimensional range-Doppler spectrum, dividing the spectrum into N subbands along the Doppler dimension based on the minimum step phase of the transmitted signal of each transmitting antenna; determining signal subbands within the N subbands based on the phase step pattern of the transmitted signal of each transmitting antenna and the energy sum of each signal subband combination, and / or determining the order of signal subbands corresponding to the transmitted signal of each transmitting antenna; wherein a signal subband is a subband containing a target peak signal. For ease of understanding, the following description mainly uses the example of uniformly dividing the Doppler spectrum to obtain N subbands.

[0109] In some embodiments, the specific flow of the signal processing method is shown in FIG9 .

[0110] In step 901 , spectrum analysis is performed on the echo signal to obtain a range-Doppler two-dimensional spectrum.

[0111] In one example, a radar system transmits a detection signal using a Doppler dimension multiplexing (DDM) mode via an antenna array. The antenna array includes at least one receiving antenna and at least two transmitting antennas. An FFT (i.e., 2D-FFT) is performed on the echo signal in both the range and Doppler dimensions to obtain a two-dimensional range-Doppler spectrum containing target data.

[0112] In step 902, any target data spectrum in the range-Doppler two-dimensional spectrum is divided into N sub-bands along the Doppler dimension based on the minimum step phase of the signal transmitted by each transmitting antenna.

[0113] In one example, if the minimum step phase of the signal transmitted by each transmitting antenna is 45°, since 360° includes 8 45° angles, 8 sub-bands are divided along the Doppler dimension, that is, N is 8. In another example, if the minimum step phase of the signal transmitted by each transmitting antenna is 60°, since 360° includes 6 60° angles, 6 sub-bands are divided along the Doppler dimension, that is, N is 6. In another example, if the minimum step phase of the signal transmitted by each transmitting antenna is 30°, since 360° includes 12 60° angles, 12 sub-bands are divided along the Doppler dimension, that is, N is 12. Of course, the above are merely examples of the minimum step phase and the corresponding Doppler spectrum division in different situations. In some embodiments, the minimum step phase and the corresponding Doppler spectrum division may also be different from the above examples, which will not be described in detail here.

[0114] In step 903, signal subbands among the N subbands are determined, and / or the order of signal subbands corresponding to the signals transmitted by each transmit antenna is determined. For example, the signal subbands among the N subbands and / or the order of signal subbands corresponding to the signals transmitted by each transmit antenna are determined based on a phase stepping pattern of the signals transmitted by each transmit antenna and the energy sum of each signal subband.

[0115] Since this embodiment is applied to a radar system with non-uniformly spaced DDM, i.e., the phase shift steps of each transmitting antenna are different, but the phase shift steps of each transmitting antenna are also determined. In other words, in the echo signal, the relative position of the signal corresponding to each transmitting antenna is determined. Furthermore, since the target energy in the signal subband is greater than the energy in the leakage subband, in this step, the signal subbands among the N subbands can be determined based on the phase step pattern of the transmitted signal from each transmitting antenna and the energy sum of each signal subband, and / or the order of the signal subbands corresponding to the transmitted signal from each transmitting antenna can be determined. The signal subband is the subband containing the target peak signal, and the leakage subband is the remaining subbands among the N subbands except for the signal subband.

[0116] In one example, by traversing all possible positional sequences of signals corresponding to multiple transmit antennas in N signals, the energy sum of the signals corresponding to the multiple transmit antennas in each positional sequence is obtained. The signals corresponding to each transmit antenna in the N signals are then determined based on the positional sequence with the largest energy sum, thereby determining the signal subband. This step is similar to step 104 and is not further described here.

[0117] Through steps 901 to 903, signal subbands among the N subbands are determined based on the phase stepping pattern of the signals transmitted by each transmitting antenna and the energy sum of each signal subband, and / or the order of signal subbands corresponding to the signals transmitted by each transmitting antenna is determined. This ensures the accuracy of channel separation for each transmitting antenna. The obtained signal subbands and / or the order of signal subbands corresponding to the signals transmitted by each transmitting antenna can be used for subsequent velocity ambiguity resolution and / or direction of arrival estimation processing, thereby ensuring accurate acquisition of target parameter data.

[0118] In addition, in one example, after step 903, step 904 may be further included, removing false targets based on a preset confidence level, wherein the preset confidence level is obtained based on signal subband energy and at least part of leakage subband energy.

[0119] In one example, the preset confidence level includes a first confidence level and / or a second confidence level, and false targets are removed based on the first confidence level and / or the second confidence level. The first confidence level is the ratio of the energy sum of the signal subband to the energy sum of all subbands, and the second confidence level is the ratio of the minimum signal subband peak to the maximum leakage subband peak. The specific implementation of false target removal based on the first confidence level and / or the second confidence level is described in detail in the above embodiments and will not be repeated here.

[0120] In addition, in another example, after step 904, step 905 may be further included, in which peak aggregation processing is performed based on the signal sub-band sequence to remove adjacent repeated false targets, resolve velocity ambiguity, and / or estimate the direction of arrival.

[0121] In one example, the energy values ​​of the pending targets can be stored in a pre-created two-dimensional matrix. The storage location of the energy values ​​of the pending targets in the two-dimensional matrix is ​​determined based on the range bin value of the pending targets in the range spectrum and the Doppler bin value of the pending targets in the Doppler spectrum. For each pending target's energy value stored in the two-dimensional matrix, a check is performed to determine whether the energy value of the pending target is greater than the energy value of a nearby pending target. If the energy value is less than the energy value of the nearby pending target, the pending target is deleted as a duplicate target.

[0122] After removing adjacent repeated false targets, the parameters of the retained targets are obtained, such as velocity deambiguation to obtain more accurate velocity data of the retained targets, and / or direction of arrival estimation to obtain angle data of the retained targets.

[0123] The steps of the above method are divided only for the purpose of clear description. During implementation, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent. Adding insignificant modifications or introducing insignificant designs to the algorithm or process without changing the core design of the algorithm and process are all within the scope of protection of this patent.

[0124] Another embodiment of the present invention relates to a computer-readable storage medium storing a computer program. Through the description of the above embodiments, it is easy for those skilled in the art to understand that the example embodiments described herein can be implemented by software or by combining software with necessary hardware. The technical solution according to the embodiment of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, and includes several instructions to enable a computing device (which can be a personal computer, a server, or a network device, etc.) to execute the above method according to the embodiment of the present application.

[0125] The software product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or component, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM, or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM, Compact Disc Read-Only Memory), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0126] Computer readable storage media can include a data signal propagated in baseband or as a carrier wave part, wherein readable program code is carried. The data signal of this propagation can take many forms, including but not limited to electromagnetic signals, optical signals or any suitable combination of the above. The readable storage medium can also be any readable medium other than a readable storage medium, which can send, propagate or transmit a program for use by an instruction execution system, device or component or used in combination with it. The program code contained on the readable storage medium can be transmitted with any appropriate medium, including but not limited to wireless, wired, optical cable, RF (Radio Frequency) or the like, or any suitable combination of the above.

[0127] The program code for performing the operations of the present application can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code can be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0128] The computer-readable medium carries one or more programs. When the one or more programs are executed by a device, the computer-readable medium implements the aforementioned functions.

[0129] Another embodiment of the present application relates to an integrated circuit, as shown in Figure 10, including: a processor 1001 and a memory 1002; the memory 1002 is used to store instructions that can be executed by at least one processor 1001, and the instructions are executed by at least one processor 1001 to enable at least one processor 1001 to execute the method embodiment described above.

[0130] The memory 1002 and processor 1001 are connected using a bus. The bus may include any number of interconnected buses and bridges, connecting various circuits of one or more processors 1001 and memory 1002. The bus may also connect various other circuits such as peripheral devices, voltage regulators, and power management circuits. These are all well known in the art and, therefore, will not be described further herein. The bus interface provides an interface between the bus and the transceiver. The transceiver may be a single component or multiple components, such as multiple receivers and transmitters, providing a unit for communicating with various other devices over a transmission medium. Data processed by the processor 1001 is transmitted over a wireless medium via an antenna. Furthermore, the antenna receives data and transmits it to the processor 1001.

[0131] The processor 1001 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. The memory 1002 can be used to store data used by the processor 1001 when performing operations.

[0132] Another embodiment of the present application relates to a radio device, comprising: a carrier; an integrated circuit such as the one in the above example, disposed on the carrier; an antenna, disposed on the carrier, or the antenna and the integrated circuit are integrated into one device and disposed on the carrier; wherein the integrated circuit is connected to the antenna for transmitting target detection signals and / or receiving echo signals.

[0133] When the antenna and integrated circuit are not integrated into a single device, the integrated circuit is connected to the antenna via a first transmission line. The first transmission line can be a PCB (Printed Circuit Board Design) trace. The carrier can be a PCB, such as a development board, data acquisition board, or device motherboard, and the details are not detailed here.

[0134] Since the structure and working principle of the integrated circuit included in the radio device have been described in detail in the above embodiments, they will not be repeated here.

[0135] Another embodiment of the present application relates to a terminal device, comprising: a device body; and a radio device as described above, which is arranged on the device body; wherein the radio device is used for target detection to provide reference information for the operation of the device body.

[0136] In one embodiment of the present application, the radio device may be disposed outside the device body. In another embodiment of the present application, the radio device may be disposed inside the device body. In still other embodiments of the present application, the radio device may be disposed partially inside the device body and partially outside the device body. This embodiment of the present application is not limited to this, and the specific circumstances may vary.

[0137] It should be noted that radio devices can perform functions such as target detection by transmitting and receiving radio signals, providing measurement information of the detected target to the device itself, thereby assisting or even controlling the operation of the device itself. Examples of measurement information include at least one of relative distance, relative speed, and relative angle.

[0138] In one embodiment, the device body can be a component or product used in fields such as transportation, consumer electronics, monitoring, in-cabin detection, and health care. For example, the device body can be intelligent transportation equipment (such as cars, motorcycles, ships, subways, trains, etc.), security equipment (such as cameras), liquid level / flow rate detection equipment, smart wearable devices (such as bracelets, glasses, etc.), smart home devices (such as sweeping robots, door locks, televisions, air conditioners, smart lights, etc.), various communication devices (such as mobile phones, tablets, etc.), as well as gates, smart traffic lights, smart signs, traffic cameras, and various industrial robotic arms (or robots). It can also be various instruments for detecting vital signs and various devices equipped with the instruments, such as in-cabin detection in cars, indoor personnel monitoring, smart medical equipment, consumer electronic devices, etc.

[0139] In another embodiment, when the above-mentioned device body is applied to an advanced driving assistance system (ADAS), the radio device as a vehicle-mounted sensor can provide the ADAS system with various functional safety guarantees such as automatic braking assistance (AEB), blind spot detection warning (BSD), lane change assistance warning (LCA), and reversing assistance warning (RCTA).

[0140] In addition, the examples mentioned in the above embodiments can be freely combined, and any combination can be understood as an embodiment. The "embodiment" or "example" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it mean that it is an independent or alternative embodiment that is mutually exclusive with other embodiments. It will be understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0141] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present application, and that in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present application.

Claims

1. A target detection method, the method comprising: Perform FFT on the echo signal to obtain the Doppler spectrum under the same range gate; Acquire energy of N signals from the Doppler spectrum; wherein the Doppler spectrum is divided into N sub-bands, and the N signals belong to the N sub-bands; Traversing all possible position sequences of signals corresponding to multiple transmitting antennas in the N signals; Obtaining energy sums of signals corresponding to the multiple transmitting antennas in each position order, and obtaining signals corresponding to each transmitting antenna among the N signals according to the position order with the largest energy sums; The target parameters are acquired based on the signal energy in each signal sub-band; wherein each signal sub-band is a sub-band to which the signals corresponding to each transmitting antenna belong.

2. The target detection method according to claim 1, wherein: The target parameters are obtained based on the signal energy in each signal sub-band, including: Determining a target to be confirmed based on the signal energy in each signal sub-band; Acquire a first confidence of the target to be confirmed, where the first confidence is used to characterize the difference between a first energy sum of the target to be confirmed and a second energy sum of the target to be confirmed, wherein the first energy sum represents an energy sum of signal energies of the target to be confirmed in each signal subband, and the second energy sum represents an energy sum of the first energy sum and the signal energy of the target to be confirmed in at least one leakage subband, and the leakage subband is a subband of the N subbands except the signal subbands; According to the first confidence level, deciding whether the target to be confirmed is a false target; When it is determined that the target to be confirmed is not a false target, target parameters of the target to be confirmed are acquired.

3. The target detection method according to claim 2, wherein: The obtaining of the first confidence level of the target to be confirmed includes: Obtaining a ratio of the sum of the first energies to the sum of the second energies; The step of determining whether the target to be confirmed is a false target according to the first confidence level includes: When the first confidence level is greater than a preset first threshold, it is determined that the target to be confirmed is not a false target.

4. The target detection method according to claim 1, wherein: The target parameters are obtained based on the signal energy in each signal sub-band, including: Determining a target to be confirmed based on the signal energy in each signal sub-band; Acquire a second confidence of the target to be confirmed, where the second confidence is used to characterize the difference between a first energy value of the target to be confirmed and a second energy value of the target to be confirmed, wherein the first energy value represents the minimum energy value of the target to be confirmed in each signal subband, and the second energy value represents the maximum energy value of the target to be confirmed in a leakage subband; wherein the leakage subband is the remaining subbands of the N subbands except the signal subbands; According to the second confidence level, deciding whether the target to be confirmed is a false target; When it is determined that the target to be confirmed is not a false target, target parameters of the target to be confirmed are acquired.

5. The target detection method according to claim 4, wherein: The obtaining of the second confidence level of the target to be confirmed includes: Obtaining a logarithm of a ratio of the first energy value to the second energy value; The step of determining whether the target to be confirmed is a false target according to the second confidence level includes: When the second confidence level is greater than a preset second threshold, it is determined that the target to be confirmed is not a false target.

6. The target detection method according to any one of claims 1 to 5, wherein: The N is determined according to a minimum phase shift step relative to a reference transmitting antenna among the multiple transmitting antennas.

7. The target detection method according to any one of claims 1 to 6, wherein: The target parameters are obtained based on the signal energy in each signal sub-band, including: Determining a target to be confirmed based on the signal energy in each signal sub-band; Deduplication processing is performed on the determined target to be confirmed, and target parameters are obtained for the target to be confirmed after the deduplication processing.

8. The target detection method according to claim 7, wherein: The deduplication process includes: storing the determined energy value of the target to be confirmed in a pre-created two-dimensional matrix, wherein the storage position of the energy value of the target to be confirmed in the two-dimensional matrix is ​​determined based on the distance dimension unit value of the target to be confirmed in the distance spectrum and the Doppler unit value in the Doppler spectrum; For each energy value of the target to be confirmed stored in the two-dimensional matrix, detect whether the energy value of the target to be confirmed is greater than the energy value of the target to be confirmed stored in a nearby position. If it is less than the energy value of the target to be confirmed stored in a nearby position, delete the target to be confirmed as a duplicate target.

9. The target detection method according to claim 8, wherein: The size of the two-dimensional matrix is ​​[Rng_nfft / 2, Vel_nfft / N], where Rng_nfft represents the number of FFT points in the distance dimension; Vel_nfft represents the number of FFT points in the Doppler dimension; The step of storing the determined energy value of the target to be confirmed in a pre-created two-dimensional matrix includes: Taking the modulus of the Doppler unit value of the target to be confirmed in the Doppler spectrum to Vel_nfft / N, and using the obtained remainder as the ordinate position of the target to be confirmed in the two-dimensional matrix; The abscissa position of the target to be confirmed in the two-dimensional matrix is ​​obtained according to the distance dimension unit value of the target to be confirmed in the distance spectrum, and the energy value of the target to be confirmed is stored in the two-dimensional matrix based on the abscissa position and the ordinate position.

10. The target detection method according to any one of claims 2 to 9, wherein: The Doppler spectrum under the same range gate is the data directly output after FFT in the range dimension and the Doppler dimension; Acquiring target parameters of the target to be confirmed includes: According to each signal sub-band, DOA estimation and / or velocity deambiguation is performed on the target.

11. The target detection method according to any one of claims 1 to 10, wherein: The Doppler spectrum is divided into N sub-bands at equal intervals, and the number of Doppler units between any two adjacent signals in the N signals is the same.

12. A target detection method, the method comprising: Performing FFT of the range dimension and the Doppler dimension on the echo signal respectively to obtain a Doppler spectrum under the same range gate, and dividing the Doppler spectrum into N sub-bands to determine each signal sub-band, wherein each signal sub-band is a sub-band to which the signal corresponding to each transmitting antenna belongs; Determining a target to be confirmed based on the signal energy in each signal sub-band; Acquire a first confidence of the target to be confirmed, where the first confidence is used to characterize the difference between a first energy sum of the target to be confirmed and a second energy sum of the target to be confirmed, wherein the first energy sum represents an energy sum of signal energies of the target to be confirmed in each signal subband, and the second energy sum represents an energy sum of the first energy sum and the signal energy of the target to be confirmed in at least one leakage subband, and the leakage subband is a subband of the N subbands except the signal subbands; According to the first confidence level, deciding whether the target to be confirmed is a false target; When it is determined that the target to be confirmed is not a false target, target parameters of the target to be confirmed are acquired.

13. The target detection method according to claim 12, wherein: In the case where it is determined that the target to be confirmed is not a false target, before acquiring the target parameters of the target to be confirmed, the method further includes: Acquire a second confidence of the target to be confirmed, where the second confidence is used to characterize the difference between a first energy value of the target to be confirmed and a second energy value of the target to be confirmed, wherein the first energy value represents the minimum energy value of the target to be confirmed in each signal subband, and the second energy value represents the maximum energy value of the target to be confirmed in a leakage subband; wherein the leakage subband is the remaining subbands of the N subbands except the signal subbands; According to the second confidence level, it is determined whether the target to be confirmed is a false target.

14. A target detection method, the method comprising: Performing FFT of the range dimension and the Doppler dimension on the echo signal respectively to obtain a Doppler spectrum under the same range gate, and dividing the Doppler spectrum into N sub-bands to determine each signal sub-band, wherein the signal sub-band is a sub-band to which the signal corresponding to each transmitting antenna belongs; Determining a target to be confirmed based on the signal energy in each signal sub-band; Acquire a second confidence of the target to be confirmed, where the second confidence is used to characterize the difference between a first energy value of the target to be confirmed and a second energy value of the target to be confirmed, wherein the first energy value represents the minimum energy value of the target to be confirmed in each signal subband, and the second energy value represents the maximum energy value of the target to be confirmed in a leakage subband; wherein the leakage subband is the remaining subbands of the N subbands except the signal subbands; According to the second confidence level, deciding whether the target to be confirmed is a false target; When it is determined that the target to be confirmed is not a false target, target parameters of the target to be confirmed are acquired.

15. A method for signal processing, the method comprising: Performing spectrum analysis on the echo signal to obtain a range-Doppler two-dimensional spectrum; For any target data spectrum in the range-Doppler two-dimensional spectrum, based on the minimum step phase of the transmitted signal of each transmitting antenna, the spectrum is divided into N sub-bands along the Doppler dimension; Determine a signal subband among the N subbands based on a phase stepping rule of a signal transmitted by each transmitting antenna and an energy sum of each signal subband combination, and / or determine a signal subband sequence corresponding to the signal transmitted by each transmitting antenna; The signal sub-band is a sub-band containing a target peak signal.

16. The signal processing method according to claim 15, wherein: The method further comprises: Peak aggregation processing is performed sequentially based on the signal sub-bands to remove adjacent repeated false targets, resolve velocity ambiguity, and / or estimate the direction of arrival.

17. The signal processing method according to claim 15 or 16, wherein: The sub-bands except the signal sub-band among the N sub-bands are all leakage sub-bands; the method further includes: Obtaining a preset confidence level based on the signal subband energy and at least a portion of the leakage subband energy; and, False targets are removed based on the preset confidence level.

18. The signal processing method according to claim 17, wherein: The preset confidence level includes a first confidence level and / or a second confidence level; and removing false targets based on the preset confidence level includes: removing false targets based on the first confidence level and / or the second confidence level; The first confidence value is the ratio of the energy sum of the signal subband to the energy sum of all subbands, and the second confidence value is the ratio of the minimum value of the signal subband peak to the maximum value of the leakage subband peak.

19. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the method according to any one of claims 1 to 11 is implemented, or the method according to claim 12 or 13, or the method according to claim 14, or the method according to any one of claims 15 to 18.

20. An integrated circuit comprising: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method as described in any one of claims 1 to 11, or the method as described in claim 12 or 13, or the method as described in claim 14, or the method as described in any one of claims 15 to 18.

21. A radio device comprising: Carrier; The integrated circuit of claim 20, disposed on a carrier; An antenna is arranged on the carrier, or the antenna and the integrated circuit are integrated into one device and arranged on the carrier; Wherein, the integrated circuit is connected to the antenna and is used for transmitting a detection signal and / or receiving an echo signal.

22. A terminal device, comprising: Equipment body; as well as, A radio device as claimed in claim 21 disposed on the device body; Wherein, the radio device is used for target detection to provide reference information for the operation of the device body.

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