Interference signal detection method and apparatus

Abstract

This application provides a method and apparatus for detecting interference signals. The method includes: receiving N frames of echo signals based on a radar-transmitted target signal, where N frames are signals returned after reflection of the target signal, and N is an integer greater than 1; obtaining N 2D-FFT plane information based on the N frames of echo signals, where each 2D-FFT plane information includes power information corresponding to range and velocity; for any one of the N 2D-FFT plane information, calculating the accumulated power information of M range gates at sampling points along the velocity dimension in that 2D-FFT plane information, where each range gate represents a range range and the M range gates are consecutive; and determining the interfered signal in the N frames of echo signals based on the accumulated power information corresponding to the M range gates. This method of characterizing interference through accumulated power information exhibits good robustness, is computationally simple, and enables low power consumption in the radar system.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a method and apparatus for detecting interference signals. Background Technology

[0002] Linear frequency modulation continuous wave (LFMCW) radar is widely used in fields such as communication and target detection, including blind spot detection, lane change assist, adaptive cruise control, and parking assist in automobiles. However, when multiple LFMCW radars are used in the same scenario, they can generate interference such as co-channel and / or adjacent-channel interference. This means that the signals received by the LFMCW radars will contain interference signals with shapes such as spikes or oscillating pulses, which will degrade the performance of the radar sensors.

[0003] In some implementations, based on the characteristic that the interference signal is a linear frequency modulated signal, that is, the frequency changes linearly with time, time-frequency analysis methods, such as short-time fourier transform (STFT), are used to extract the interference features.

[0004] However, this detection method requires a large amount of signal data processing resources, and the radar system has high power consumption and poor timeliness. Summary of the Invention

[0005] This application provides an interference signal detection method and apparatus to solve the problems of high power consumption and poor timeliness of existing detection methods.

[0006] In a first aspect, embodiments of this application provide an interference signal detection method, including:

[0007] Based on radar-transmitted target signals;

[0008] Receive N frames of echo signals, where N frames are the signals returned after the target signal is reflected, and N is an integer greater than 1;

[0009] Based on N frames of echo signals, N 2D-FFT plane information are obtained, and each 2D-FFT plane information includes power information corresponding to distance and velocity.

[0010] For any 2D-FFT plane information among N 2D-FFT plane information, calculate the cumulative power information of M distance gates at the sampling points along the velocity dimension in any 2D-FFT plane information. The distance gate is a distance range, the M distance gates are continuous, and M is an integer greater than 1.

[0011] Based on the accumulated power information corresponding to the M distance gates, the signal that is interfered with in the N frames of echo signals is determined.

[0012] In one possible implementation, based on the accumulated power information corresponding to the M distance gates, the interfered signals in the N frames of echo signals are determined, including:

[0013] For any first frame echo signal and second frame echo signal in N frames of echo signals, calculate the difference between the accumulated power information of the first frame echo signal and the second frame echo signal in the distance gate with the same index value, and obtain L absolute values ​​of the difference, where L is an integer greater than 1 and less than or equal to M.

[0014] When there is a target difference absolute value among the L difference absolute values ​​that is greater than the first threshold, the echo signal with the larger accumulated power information in the target range gate in the first frame echo signal and the second frame echo signal is determined to be the signal that has been interfered with; the target range gate is the range gate used to calculate the target difference absolute value.

[0015] In one possible implementation, the first frame echo signal is a signal received prior to the second frame echo signal, and the method further includes:

[0016] If the first frame echo signal is a interfered signal, disable the anti-interference mechanism;

[0017] If the second frame echo signal is a interfered signal, the anti-interference mechanism is activated.

[0018] In one possible implementation, based on the accumulated power information corresponding to the M distance gates, the interfered signals in the N frames of echo signals are determined, including:

[0019] For any third and fourth frame echo signals in N frames of echo signals, calculate the power difference between the third and fourth frame echo signals in the first distance gate to obtain the absolute value of the first difference. The first distance gate is any one of M distance gates.

[0020] When the absolute value of the first difference is greater than the first threshold, the echo signal with the larger accumulated power information when calculating the first distance gate in the first frame echo signal and the second frame echo signal is determined to be the signal that has been interfered with.

[0021] In one possible implementation, based on the accumulated power information corresponding to the M distance gates, the interfered signals in the N frames of echo signals are determined, including:

[0022] If any of the accumulated power information corresponding to the M distance gates of the fifth frame echo signal in the N-frame echo signal is greater than the second threshold, the fifth frame echo signal is determined to be a signal subject to interference.

[0023] In one possible implementation, N 2D-FFT planar information units are obtained based on N frames of echo signals, including:

[0024] The N frames of echo signals are down-frequency processed to obtain N intermediate frequency signals;

[0025] Two-dimensional fast Fourier transforms are performed on N intermediate frequency signals to obtain N 2D-FFT plane information.

[0026] In one possible implementation, the radar is a millimeter-wave radar.

[0027] Secondly, embodiments of this application provide an interference signal detection device, comprising:

[0028] The transmission module is used to transmit target signals based on radar.

[0029] The receiving module is used to receive N frames of echo signals, which are the signals returned after the target signal is reflected, where N is an integer greater than 1.

[0030] The first determining module is used to obtain N 2D-FFT plane information based on N frames of echo signals, where each 2D-FFT plane information includes power information corresponding to distance and velocity.

[0031] The calculation module is used to calculate the cumulative power information of M distance gates along the velocity dimension of any 2D-FFT plane information for any one of N 2D-FFT plane information. The distance gate is a distance range, the M distance gates are consecutive, and M is an integer greater than 1.

[0032] The second determining module is used to determine the interfered signals in the N frames of echo signals based on the accumulated power information corresponding to the M distance gates.

[0033] In one possible implementation, the second determining module is specifically used for:

[0034] For any first and second frame echo signals in N frames of echo signals, calculate the difference in accumulated power information of the first and second frame echo signals in the range gate with the same index value, respectively, to obtain L absolute values ​​of the difference, where L is an integer greater than 1 and less than or equal to M; when there is a target difference absolute value greater than a first threshold among the L absolute values ​​of the difference, determine that the echo signal with larger accumulated power information in the target range gate in the first and second frame echo signals is the signal that has been interfered with; the target range gate is the range gate used to calculate the target difference absolute value.

[0035] In one possible implementation, the first frame echo signal is a signal received prior to the second frame echo signal, and further includes:

[0036] The judgment module is used to disable the anti-interference mechanism if the first frame echo signal is an interfered signal, and to activate the anti-interference mechanism if the second frame echo signal is an interfered signal.

[0037] In one possible implementation, the second determining module is specifically used for:

[0038] For any third and fourth frame echo signals in N frames of echo signals, calculate the power difference between the third and fourth frame echo signals in the first distance gate to obtain the first absolute value of the difference. The first distance gate is any one of M distance gates. When the first absolute value of the difference is greater than the first threshold, the echo signal with the larger accumulated power information when calculating the first distance gate in the first and second frame echo signals is determined to be the signal that has been interfered with.

[0039] In one possible implementation, the second determining module is specifically used for:

[0040] If any of the accumulated power information corresponding to the M distance gates of the fifth frame echo signal in the N-frame echo signal is greater than the second threshold, the fifth frame echo signal is determined to be a signal subject to interference.

[0041] In one possible implementation, the first determining module is specifically used to perform down-frequency processing on the N frames of echo signals to obtain N intermediate frequency signals; and to perform two-dimensional fast Fourier transform on the N intermediate frequency signals to obtain N 2D-FFT plane information.

[0042] Thirdly, an interference signal detection method, applicable to FMCW sensors, includes:

[0043] Perform 2D-FFT processing on the echo signal to obtain at least two frames of distance-velocity data;

[0044] For any frame of range-velocity data, select at least a portion of the range gates, and accumulate the energy of each range gate along the velocity dimension to obtain the accumulated energy value of each range gate; and

[0045] The difference between the energy accumulation values ​​between the same index value and the distance gate of any two frames of distance-velocity data is obtained to determine whether the echo signal corresponding to each frame of distance-velocity data is interfered with.

[0046] In one possible implementation, the difference in energy accumulation between the same index value of the range gate in any two frames of range-velocity data is obtained to determine whether the echo signal corresponding to each frame of range-velocity data is interfered with, including:

[0047] The energy accumulation value of the distance gate at the predetermined index value in the first frame of distance-velocity data is determined as the first energy accumulation value;

[0048] The energy accumulation value of the distance gate with the same predetermined index value in the second frame distance-velocity data is determined as the second energy accumulation value;

[0049] The difference is obtained by subtracting the second energy accumulation value from the first energy accumulation value.

[0050] If the absolute value of the difference is greater than the preset threshold and the difference is positive, then the echo signal corresponding to the distance-velocity data in the first frame is determined to be an interfered signal, and the echo signal corresponding to the distance-velocity data in the second frame is determined to be an undisturbed signal.

[0051] If the absolute value of the difference is greater than the preset threshold and the difference is negative, then the echo signal corresponding to the distance-velocity data of the second frame is determined to be an interfered signal, and the echo signal corresponding to the distance-velocity data of the first frame is determined to be an undisturbed signal.

[0052] If the absolute value of the difference is less than or equal to the preset threshold, then the echo signal corresponding to the distance-velocity data in the first frame and the echo signal corresponding to the distance-velocity data in the second frame are both undisturbed signals.

[0053] The preset threshold is greater than the threshold for CFAR processing of the echo signal.

[0054] In one possible implementation, when it is determined that the echo signal corresponding to the first frame distance-velocity data and the echo signal corresponding to the second frame distance-velocity data are both undisturbed signals, if the first energy accumulation value is greater than a preset average threshold, then it can be determined that the echo signal corresponding to the first frame distance-velocity data contains target information.

[0055] Fourthly, embodiments of this application provide an interference signal detection device, comprising: at least one processor and a memory;

[0056] The memory stores the instructions that the computer executes;

[0057] At least one processor executes computer execution instructions stored in memory, causing the at least one processor to perform the method described in the first aspect or any implementation thereof, or to perform the method described in the third aspect or any implementation thereof.

[0058] Fifthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions. When a processor executes the computer-executable instructions, it implements the method described in the first aspect or any implementation thereof, or performs the method described in the third aspect or any implementation thereof.

[0059] In this embodiment, based on the radar transmitting a target signal, N frames of echo signals are received. These N frames are the signals returned after reflection from the target signal, where N is an integer greater than 1. Based on these N frames, N 2D-FFT plane information pieces are obtained. Each 2D-FFT plane information piece includes power information corresponding to range and velocity. For any one of the N 2D-FFT plane information pieces, the accumulated power information of M range gates along the velocity dimension of each 2D-FFT plane information piece is calculated. Each range gate represents a range range, and the M range gates are consecutive, where M is an integer greater than 1. Based on the accumulated power information corresponding to the M range gates, the signal affected by interference in the N frames of echo signals is determined. This method of characterizing interference through accumulated power information exhibits good robustness, is computationally simple, and enables low power consumption in the radar system. Attached Figure Description

[0060] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of the embodiments of this application.

[0061] Figure 1 This is a schematic diagram of mutual interference between LFMCW radars.

[0062] Figure 2 This is a schematic diagram of the interference waveform of an LFMCW radar.

[0063] Figure 3 This is a schematic diagram illustrating the scenario to which the embodiments of this application apply;

[0064] Figure 4 A flowchart illustrating an interference signal detection method provided in an embodiment of this application;

[0065] Figure 5 This is a schematic diagram of 2D-FFT planar information;

[0066] Figure 6a This is a time-domain plot of a single linear frequency modulated signal of the LFMCW radar echo signal under interference-free conditions.

[0067] Figure 6b This is a schematic diagram of the 3D information corresponding to the 2D-FFT planar information of the LFMCW radar echo signal under an interference-free condition.

[0068] Figure 6c This application provides a schematic diagram of the accumulated power information of 2D-FFT for each distance gate under interference-free conditions in an embodiment of the present application.

[0069] Figure 7a This is a time-domain diagram of a single linear frequency modulated signal of an LFMCW radar echo signal under interference conditions.

[0070] Figure 7b This is a schematic diagram of the 3D information corresponding to the 2D-FFT planar information of the LFMCW radar echo signal under interference conditions.

[0071] Figure 7c This application provides a schematic diagram of the 2D-FFT accumulated power information of each distance gate under interference conditions, as shown in the embodiments of this application.

[0072] Figure 8 This is a schematic diagram of a framework for obtaining 2D-FFT planar information;

[0073] Figure 9 This is a schematic diagram of the structure of an interference signal detection device provided in an embodiment of this application;

[0074] Figure 10 This is a schematic diagram of the structure of an interference signal detection device provided in an embodiment of this application.

[0075] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0076] To facilitate a clear description of the technical solutions in the embodiments of this application, some terms and technologies involved in the embodiments of this application will be briefly introduced below:

[0077] 1) Noise floor: Also known as the noise floor, it represents the minimum signal strength that a receiver can perceive when the received signal-to-noise ratio (SNR) is 0 dB. Receiver sensitivity = noise floor + SNR. Noise limits the minimum signal strength that a circuit can correctly process; signals below the noise floor cannot be processed correctly.

[0078] 2) Other terms

[0079] In the embodiments of this application, terms such as "first" and "second" are used to distinguish identical or similar items with substantially the same function and purpose. For example, "first chip" and "second chip" are used only to distinguish different chips and do not limit their order of execution. Those skilled in the art will understand that terms such as "first" and "second" do not limit the quantity or execution order, and that "first" and "second" do not necessarily imply that they are different.

[0080] It should be noted that, in the embodiments of this application, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design scheme described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0081] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, a--c, bc, or abc, where a, b, and c can be single or multiple.

[0082] LFMCW radar is widely used in fields such as communication and target detection. For example, it can be used for target detection in automotive millimeter-wave radar systems.

[0083] For example, in an automotive millimeter-wave radar system, the transmitter continuously transmits multiple linear frequency modulated (LFMCW) signals. The receiver down-converts the received LFMCW reflected signals to obtain a baseband (or intermediate frequency) signal, and then performs a 2D Fast Fourier Transform (FFT) on the baseband signal. The first dimension is the FFT within each chirp signal, i.e., the range-dimensional FFT; the second dimension is the value at the same spectral line position within the FFT spectrum of all chirp signals, which is then subjected to another FFT operation, i.e., the Doppler-dimensional (also known as the velocity-dimensional) FFT. In the resulting 2D-FFT plane, targets at different distances and velocities will appear as peaks at different coordinates. The stronger the reflection of the target, the higher the peak value will be. The target detection process involves searching for peaks in the 2D-FFT plane. When the value at a certain coordinate in the 2D-FFT is higher than a certain detection threshold, such as the noise floor of the 2D-FFT plane, and meets certain specific conditions, it can be considered a target. The distance dimension and Doppler dimension coordinates corresponding to this coordinate correspond to the distance and velocity of the target, respectively.

[0084] In practical applications, when multiple LFMCW radars are used in the same scenario, they will interfere with each other. That is, the signals received by the LFMCW radars will generate interference signals with shapes such as spikes or oscillating pulses, which will reduce the working performance of the radar sensors.

[0085] For example, Figure 1 A schematic diagram of LFMCW radar mutual interference is shown. (For example...) Figure 1 As shown, because the slopes of the interfering radar signal (e.g., a linear frequency modulated continuous wave signal transmitted by another radar system) and the locally transmitted frequency modulated signal are different, the interference is a segment of linear frequency modulated signal. This interference signal, after low-pass filtering, generally appears as a spike or oscillating pulse. Of course, the interference is more severe when the slopes of the frequency modulated continuous waves transmitted by different radar systems are approximately or even the same. Furthermore, the aforementioned interference can occur between transmitted signals from different radars, between echo signals, and / or between transmitted and echo signals.

[0086] For example, Figure 2 A schematic diagram of an LFMCW radar waveform under interference is shown, where different interference signals are marked with dashed boxes. These interference signals can have significantly different amplitudes, and their amplitudes can be similar to those of normal signals. Since pulse interference can raise the noise floor of the spectrum or create false alarms, it can adversely affect radar detection results (e.g., failure to identify targets or incorrect target identification). Therefore, it is necessary to identify whether the current signal is under interference in order to take appropriate measures to remove the interference signal.

[0087] In some implementations, based on the characteristic that the interference signal is a linear frequency modulated signal, that is, the frequency changes linearly with time, time-frequency analysis is used to extract the interference features.

[0088] For example, STFT is used to extract interference features. That is, STFT is calculated in real time based on the data of each sampling point in each chirp signal in the frame signal. The energy of each sampling point is judged in turn to determine whether there is a sudden change. If a sudden change in energy is found after the data of each sampling point is processed, it is considered that there is interference.

[0089] However, this real-time STFT calculation for each sampling point is computationally intensive, places high demands on the system's real-time performance, and the interference situation can only be determined after processing the data at each sampling point, resulting in poor timeliness.

[0090] In view of this, embodiments of this application provide an interference signal detection method. This method calculates the accumulated power information of each range gate along the velocity dimension in the 2D-FFT plane information, and compares the accumulated power information of range gates with the same index value across different 2D-FFTs to determine whether the current frame signal is interfered with. This method of characterizing interference through accumulated power information has good robustness, is computationally simple, and enables low power consumption in radar systems.

[0091] Figure 3 The diagram illustrates a scenario to which the embodiments of this application are applicable. This scenario may include two or more radars, or any two or more sensors emitting FMCW waves may be applicable. Mutual interference between radar signals may exist in this scenario.

[0092] Radar is an electronic device that uses electromagnetic waves to detect targets. It is also called a radar device, detector, or detection apparatus. Its working principle is that the radar emits electromagnetic waves (also called transmitted or detected signals) to illuminate the target. The radar receiver receives the reflected signals from the target and displays the echo signals on the radar display, thereby obtaining information such as the distance from the target to the electromagnetic wave emission point, the rate of change of distance (radial velocity), and azimuth.

[0093] like Figure 3 As shown, the main device 100 and the jamming device 200 can be any device equipped with radar, such as motor vehicles, drones, railcars, air conditioners, speed measuring devices, or network equipment (such as base stations and terminal equipment in various systems). This application embodiment is applicable to radar systems between devices equipped with radar. This application embodiment does not limit the location and function of the radar installation.

[0094] This application uses the main device 100 and the jamming device 200 as examples of motor vehicles for illustration, and this example does not constitute a limitation on the embodiments of this application.

[0095] The radar in the main device 100 can detect radar signals in the main device 100 that are interfered with by the radar of the interference device 200 based on the interference signal detection method provided in the embodiments of this application.

[0096] For example, an interference signal detection method may include: based on a radar-transmitted target signal, receiving N frames of echo signals, where N frames are signals returned after reflection of the target signal, and N is an integer greater than 1; obtaining N 2D-FFT plane information based on the N frames of echo signals, where each 2D-FFT plane information includes power information corresponding to range and velocity; for any one of the N 2D-FFT plane information, calculating the accumulated power information along the velocity dimension of each of the M range gates, where the range gates are sampling points, and M is an integer greater than 1; and determining the interfered signal in the N frames of echo signals based on the accumulated power information corresponding to the M range gates. This method of characterizing interference through accumulated power information exhibits good robustness, is computationally simple, and enables low power consumption in the radar system.

[0097] The technical solutions of the embodiments of this application will be described in detail below through specific examples. The following embodiments can be combined with each other or implemented independently, and the same or similar concepts or processes may not be described again in some embodiments.

[0098] Figure 4 This is a flowchart illustrating an interference signal detection method provided in an embodiment of this application. Figure 4 As shown, the method may include:

[0099] S401: Target signal transmitted based on radar.

[0100] The radar can be millimeter-wave radar, which refers to radar operating in the millimeter-wave frequency band. Millimeter waves typically refer to the 30–300 gigahertz (GHz) frequency range (wavelength 1–10 mm). For example, automotive millimeter-wave radar primarily operates in the 77 GHz band. The target signal can be a uniformly timed chirp signal sequence.

[0101] In this embodiment, a target signal can be transmitted when a radar-equipped device activates its target detection functions. For example, when a user activates functions such as reversing or navigation in a car, the LFMCW radar transmits a sequence of chirp signals at uniform time intervals. This embodiment does not limit the specific application scenario.

[0102] S402: Receive N frames of echo signals, where N frames are the signals returned after the target signal is reflected; where N is an integer greater than 1.

[0103] In this embodiment of the application, each frame of echo signal may include multiple chirp signals.

[0104] For example, the target signal emitted by the LFMCW radar is reflected back to the radar by the target object. The radar receives the reflected signal, i.e., the echo signal. The target object can be any object that can reflect the target signal, such as obstacles, pedestrians, signaling devices, etc. This application does not make any specific limitation on this.

[0105] S403: Based on N frames of echo signals, obtain N 2D-FFT plane information, where each 2D-FFT plane information includes power information corresponding to distance and velocity.

[0106] Among them, power information can be converted into energy information.

[0107] In a possible implementation, for FMCW radar (or sensor), the baseband signal (or intermediate frequency signal) is obtained by down-converting (or mixing) the echo signal. Then, the baseband signal is converted from analog to digital (ADC) and the resulting signal is subjected to a 2D Fourier transform to obtain the corresponding 2D-FFT plane information, that is, range-velocity (or Doppler) data.

[0108] For example, Figure 5 A schematic diagram of 2D-FFT planar information is shown, such as Figure 5 As shown, the 2D-FFT planar information may include information on the target object's range dimension, velocity dimension (also known as Doppler dimension), and power information corresponding to the range and velocity. The range dimension information may include, for example, M range gates, and the velocity dimension information may include, for example, K Doppler gates. The interference signal detection method in this embodiment, based on the aforementioned range-velocity data, accumulates the energy of each range gate and determines whether the echo signal of each frame is interfered with based on the accumulated energy value. The accumulated energy value can also be accumulated power information.

[0109] For example, the echo signal can first be processed by 2D-FFT to obtain at least two frames of range-velocity data; then, for each frame of range-velocity data, the energy of each range gate is accumulated along the velocity dimension to obtain the energy accumulation value of each range gate; then, based on comparing the magnitude of the energy accumulation value of the range gate at the same index value between different frames of range-velocity data, it can be determined whether the echo signal corresponding to each frame of range-velocity data is interfered with.

[0110] In the above embodiments, when comparing any two frames of distance-velocity data, a preset number or index value of distance gates can be selected for comparison, or all distance gates can be compared one by one, and the results of the comparison and the preset threshold range can be used to determine whether the echo signal of each frame is interfered with. The specific settings can be determined according to actual needs.

[0111] Similarly, for a sensing system, if it is necessary to determine in real time whether the echo signal of the current frame is interfered with, the distance-velocity data corresponding to the echo signal of the previous frame can be selected for comparison. If it is determined that the energy accumulation value of each distance gate or most of the distance gates in the current frame is greater than the energy accumulation value of the corresponding distance gates in the previous frame, and the increased energy value is also greater than the preset threshold, then it can be determined that the current frame is interfered with. At this time, measures such as activating the interference suppression device can be taken to reduce or avoid the subsequent echo signal being interfered with by the signals emitted by other sensing systems.

[0112] Correspondingly, if the increased energy value is less than the preset threshold but greater than the threshold for constant false alarm (CFAR) processing or other thresholds for target determination, then the currently received echo signal can be considered to contain target information, allowing for further verification of the target detection results. Similarly, if the increased energy value is less than the aforementioned preset threshold, then the current frame echo signal can be considered to be uninterrupted.

[0113] It is important to note that the above judgment is based on the prior knowledge that the echo signal of the previous frame was an undisturbed signal. If it is prior knowledge that the echo signal of the previous frame was distorted, the same judgment and comparison steps are used. If the increased energy value is positive, or if the increased energy value is negative but the corresponding absolute value is small, then the echo signal of the current frame is still judged to be distorted. In this case, if the interference suppression device is not activated, it will be activated; if it is already activated, the same state will remain unchanged. However, if the increased energy value is negative and the corresponding absolute value is greater than the aforementioned threshold, then the echo signal of the current frame can be considered to have recovered from the distorted state. In this case, the interference suppression device can be turned off, or the interference suppression device can be kept in an inactive state.

[0114] In summary, this embodiment determines whether the echo signal corresponding to each frame of distance-velocity data is interfered with by accumulating energy along the velocity dimension for each distance gate based on at least two frames of distance-velocity data obtained through 2D-FFT processing of the echo signal, and then comparing the difference in the energy accumulation values ​​of the same index (or sequence number) distance gate between different frames of distance-velocity data. Generally, as long as the difference in the energy accumulation value changes abruptly (e.g., the absolute value of the difference is greater than a preset threshold), it can be determined that the echo signal corresponding to one frame of distance-velocity data is an interfered signal. As for the positional relationship between the echo signals corresponding to the two frames of distance-velocity data being compared, this embodiment does not limit it. It can be the echo signals corresponding to two consecutive frames of distance-velocity data, or the echo signals corresponding to two frames of distance-velocity data separated by a certain time interval, or even the echo signal corresponding to a specific (or preset) frame of distance-velocity data can be used as a reference, and the echo signals corresponding to the other frames of distance-velocity data are all related to this specific frame. By comparing the echo signals corresponding to each frame of distance-velocity data, it is possible to quickly determine whether the echo signal of the compared frame of distance-velocity data is an interfered frame signal, and even roughly determine whether the echo signal corresponding to the frame of distance-velocity data contains target information. Similarly, when comparing two frames of distance-velocity data, the embodiments of this application do not limit the number of distance gates to be compared. All distance gates in a frame of distance-velocity data can be compared, some distance gates can be compared, or a portion of distance gates can be selected for comparison. The specific method can be adjusted according to actual needs, as long as the purpose of comparison can be achieved.

[0115] For example, taking vehicle-mounted millimeter-wave radar as an example, when dealing with special application scenarios where the environment is relatively stable, such as highways and parking lots, a reference range gate energy value can be set in conjunction with the target distance and speed (that is, the energy accumulation value obtained by selecting two or more range gates and accumulating them) to compare different frames, so as to make judgments and processes more quickly and accurately.

[0116] It should be noted that the premise of this application is that the number of range gates corresponding to the echo signals of each frame is the same, and the processing steps of various signals and data are also the same. Only in this way can it have practical application value when comparing different frames.

[0117] S404: For any 2D-FFT plane information among N 2D-FFT plane information, calculate the cumulative power information of M distance gates at the sampling points along the velocity dimension in any 2D-FFT plane information. The distance gate is a distance range, and the M distance gates are consecutive; where M is an integer greater than 1.

[0118] The velocity dimension can also be called Doppler dimension, and for ease of expression, it will be referred to as Doppler dimension below.

[0119] In a possible implementation, in any 2D-FFT plane information, the power information of any sampling point along the Doppler dimension of any distance gate is extracted and summed to obtain the accumulated power information of any distance gate.

[0120] For example, such as Figure 5 As shown, the power information for the m-th distance from the gate edge velocity dimension can be, for example, P1, P2…P K Regarding the power information P1, P2…P K Perform a summation operation to obtain the accumulated power information of the m-th distance gate.

[0121] Understandably, when calculating the accumulated power information of any range gate, a subset of the power information from the sampling points along the Doppler dimension of that range gate can be selected and summed. Alternatively, the accumulated power information of a specific range gate can also be calculated.

[0122] S405: Based on the accumulated power information corresponding to the M distance gates, determine the signal that is interfered with in the N frames of echo signals.

[0123] In one possible implementation, the accumulated power information of the distance gate in any frame of echo signal is subtracted from the preset accumulated power information, and the signal that is interfered with in the N frames of echo signal is determined based on the result of the subtraction operation.

[0124] In another possible implementation, the accumulated power information of the distance gate with the same index value between different frame echo signals is subtracted, and the signal that is interfered with in the N frame echo signals is determined based on the result of the subtraction operation.

[0125] In summary, this application provides an interference signal detection method. This method is based on a radar transmitting a target signal and receiving N frames of echo signals. The N frames of echo signals are the signals returned after reflection from the target signal, where N is an integer greater than 1. Based on the N frames of echo signals, N 2D-FFT plane information are obtained. Each 2D-FFT plane information includes power information corresponding to range and velocity. For any one of the N 2D-FFT plane information, M range gates are calculated, representing the accumulated power information along the velocity dimension in that 2D-FFT plane information. The range gates are sampling points, and M is an integer greater than 1. Based on the accumulated power information corresponding to the M range gates, the interfered signal in the N frames of echo signals is determined. This method of characterizing interference through accumulated power information exhibits good robustness, is computationally simple, and enables low power consumption in the radar system.

[0126] Specifically, this application provides an interference signal detection method that can be applied to an FMCW sensor. The method may include:

[0127] The echo signal is processed by 2D-FFT to obtain at least two frames of range-velocity data; for any frame of range-velocity data, at least some range gates are selected, and energy is accumulated along the velocity dimension for each range gate to obtain the energy accumulation value of each range gate; and the difference between the energy accumulation values ​​of the range gates at the same index value of any two frames of range-velocity data is obtained to determine whether the echo signal corresponding to each frame of range-velocity data is interfered with.

[0128] Optionally, the difference between the energy accumulation values ​​between the same index value and the distance gate of any two frames of distance-velocity data can be obtained to determine whether the echo signal corresponding to each frame of distance-velocity data is interfered with, including:

[0129] The energy accumulation value of the distance gate at the predetermined index value in the first frame of distance-velocity data is determined as the first energy accumulation value;

[0130] The energy accumulation value of the distance gate with the same predetermined index value in the second frame distance-velocity data is determined as the second energy accumulation value;

[0131] The difference is obtained by subtracting the second energy accumulation value from the first energy accumulation value.

[0132] If the absolute value of the difference is greater than the preset threshold and the difference is positive, then the echo signal corresponding to the distance-velocity data in the first frame is determined to be an interfered signal, and the echo signal corresponding to the distance-velocity data in the second frame is determined to be an undisturbed signal.

[0133] If the absolute value of the difference is greater than the preset threshold and the difference is negative, then the echo signal corresponding to the distance-velocity data of the second frame is determined to be an interfered signal, and the echo signal corresponding to the distance-velocity data of the first frame is determined to be an undisturbed signal.

[0134] If the absolute value of the difference is less than or equal to the preset threshold, then the echo signal corresponding to the distance-velocity data in the first frame and the echo signal corresponding to the distance-velocity data in the second frame are both undisturbed signals.

[0135] The preset threshold is greater than the threshold for CFAR processing of the echo signal.

[0136] Optionally, when both the echo signals corresponding to the first frame of distance-velocity data and the echo signals corresponding to the second frame of distance-velocity data are determined to be interference-free signals, if the first energy accumulation value is greater than a preset average threshold, then the echo signal corresponding to the first frame of distance-velocity data can be considered to contain target information. The aforementioned preset average threshold can be based on big data analysis; in special application scenarios where there is no interference and no target information, the preset average threshold can be the average value of the energy accumulation values ​​corresponding to one or more distance gates in a frame of signal.

[0137] Optional, in Figure 4 Based on the corresponding embodiments, in one possible implementation, the signal affected by interference in the N frames of echo signals is determined according to the accumulated power information corresponding to the M distance gates, including:

[0138] For any first and second frame echo signals in N frames of echo signals, calculate the difference in accumulated power information of the first and second frame echo signals in the range gate with the same index value, respectively, to obtain L absolute values ​​of the difference; where L is an integer greater than 1 and less than or equal to M; when there is a target difference absolute value greater than a first threshold among the L absolute values ​​of the difference, determine that the echo signal with larger accumulated power information in the target range gate in the first and second frame echo signals is the signal that has been interfered with; the target range gate is the range gate used to calculate the target difference absolute value.

[0139] The first and second echo frames can be any two echo frames from the N echo frames, such as two adjacent echo frames or two echo frames spaced apart by multiple frames. The distance gates with the same index value can be distance gates corresponding to the same distance dimension index value in different echo frames. The distance dimension index values ​​are the same in different echo frames, and the range of the distance dimension index value can be 1, 2...m...M. For example, the m-th distance gate in the first echo frame and the m-th distance gate in the second echo frame have the same index value.

[0140] In this embodiment, the difference between the accumulated power information of the first and second frame echo signals at the same index value range gate is calculated. Multiple absolute values ​​of these differences are then compared with a first threshold to determine whether any interfered signals exist in the first and second frame echo signals. The echo signal with the larger accumulated power information in the target range gate is identified as the interfered signal. This method of determining interfered signals based on accumulated power information in the range dimension is computationally simple, effectively reduces data resource consumption, achieves low power consumption in the radar system, and has strong timeliness.

[0141] Optionally, the first frame echo signal is a signal received before the second frame echo signal. The method further includes: if the first frame echo signal is an interfered signal, disabling the anti-interference mechanism; if the second frame echo signal is an interfered signal, activating the anti-interference mechanism.

[0142] In this embodiment, the first frame echo signal is the signal received before the second frame echo signal; for example, the first frame echo signal is the previous frame echo signal, and the second frame echo signal is the current frame echo signal. The anti-jamming mechanism can be an anti-jamming measure in the radar system, such as a "wide-limited-narrow" anti-wideband noise frequency modulation interference mechanism.

[0143] For example, when it is confirmed that the echo signal of the current frame is a signal subject to interference, the anti-interference mechanism is activated to suppress the interference. When it is confirmed that the echo signal of the previous frame was a signal subject to interference, that is, the interference has ended by the time the echo signal of the current frame arrives, the anti-interference mechanism is deactivated.

[0144] In this embodiment, the anti-interference mechanism is activated when an interference signal is detected and deactivated when there is no interference signal. Compared to keeping the anti-interference mechanism always on, the running time of the anti-interference mechanism is reduced, thereby reducing the negative impact of the anti-interference mechanism on the radar system.

[0145] Optionally, based on the accumulated power information corresponding to the M distance gates, the interfered signals in the N frames of echo signals are determined, including:

[0146] For any third and fourth frame echo signals in N frames of echo signals, calculate the power difference between the third and fourth frame echo signals in the first distance gate to obtain the first absolute value of the difference. The first distance gate is any one of M distance gates. When the first absolute value of the difference is greater than the first threshold, the echo signal with the larger accumulated power information when calculating the first distance gate in the first and second frame echo signals is determined to be the signal that has been interfered with.

[0147] The third and fourth echo signals can be any two echo signals from the N echo signals, such as two adjacent echo signals or two echo signals spaced apart by multiple frames. The power difference is the difference between the accumulated power information of the two echo signals at the same index value in the distance gate, and the absolute value of the first difference refers to the absolute value of the power difference.

[0148] In a possible implementation, only the absolute value of the first difference between any two echo signals in the N-frame echo signals at any distance gate with the same index value can be calculated.

[0149] It is understandable that, under interference conditions, the power accumulation information corresponding to any distance gate is greater than the power accumulation information of the corresponding distance gate under interference-free conditions.

[0150] For example, Figure 6a A time-domain plot of a single linear frequency modulated (LFM) signal from an LFMCW radar echo signal under interference-free conditions is shown. Figure 6a As shown, the graph includes time and amplitude information, with both positive and negative amplitudes within 1500. Figure 6a On this basis, Figure 6b This diagram illustrates the 3D information corresponding to the 2D-FFT planar information of an LFMCW radar echo signal under interference-free conditions. Figure 6b As shown in the figure, this diagram includes the correspondence between range dimension, Doppler dimension, and power. High power peaks (the areas with protrusions in the diagram) 601 correspond to targets detected by radar, while low power peaks (the flat areas in the diagram) 602 can correspond to the noise floor of 2D-FFT planar information. For example... Figure 6b As shown, under interference-free conditions, the power peak corresponding to the noise floor of 2D-FFT planar information is low and uniform. Figure 6b On this basis, Figure 6c This illustration shows a schematic diagram of the accumulated power information of each distance gate under an interference-free condition, according to an embodiment of this application. Figure 6c As shown in the figure, the figure includes accumulated power information and distance dimension information. The power accumulation information corresponding to each distance gate is almost all less than 140dB.

[0151] For example, Figure 7a A time-domain plot of a single linear frequency modulated (LFM) signal from an LFMCW radar echo signal under interference conditions is shown. Figure 7a As shown, the graph includes time and amplitude information, with both positive and negative amplitudes around 15,000, exceeding ten times the amplitudes under interference-free conditions. Figure 7a On this basis, Figure 7b This diagram illustrates the 3D information corresponding to the 2D-FFT planar information of an LFMCW radar echo signal under interference conditions. Figure 7b As shown in the figure, this diagram includes the correspondence between range dimension, Doppler dimension, and power. High power peaks (the areas with protrusions in the diagram) 701 correspond to targets detected by radar, while low power peaks (the flat areas in the diagram) 702 can correspond to the noise floor of 2D-FFT planar information. For example... Figure 7b As shown, under interference conditions, the power peak corresponding to the noise floor of the 2D-FFT planar information is significantly improved compared to the interference-free condition. Figure 7b On this basis, Figure 7c This illustration shows a schematic diagram of the accumulated power information of each distance gate under interference conditions, provided by an embodiment of this application. For example... Figure 7c As shown, this figure includes accumulated power information and distance dimension information. Based on Figure 6c and Figure 7c It can be seen that, due to the influence of interference signals, the power accumulation information corresponding to any distance gate under interference conditions is greater than the power accumulation information of the corresponding distance gate under non-interference conditions.

[0152] In this embodiment, the absolute value of the first difference between any two echo signals in N frames of echo signals at any distance gate with the same index value is calculated, and then the absolute value of the first difference is compared with a first threshold to determine the signal that is being interfered with. This reduces the amount of calculation of the accumulated power information of the distance gate and further reduces the power consumption of the system.

[0153] Optionally, based on the accumulated power information corresponding to the M distance gates, the interfered signals in the N frames of echo signals are determined, including:

[0154] If any of the accumulated power information corresponding to the M distance gates of the fifth frame echo signal in the N-frame echo signal is greater than the second threshold, the fifth frame echo signal is determined to be a signal subject to interference.

[0155] The second threshold can be accumulated power information preset based on a specific scenario, such as a highway or parking lot where environmental conditions are relatively stable. The fifth echo signal can be any one of the N echo signals.

[0156] In this embodiment, the interfered signal is determined by comparing the accumulated power information of any distance gate of any frame of echo signal in N frames with the accumulated power information preset based on a specific scenario. This skips the comparison of distance gates in other frames of echo signals and provides a more targeted comparison based on a specific scenario, which can effectively improve the efficiency and accuracy of interference signal detection.

[0157] Optionally, based on N frames of echo signals, N 2D-FFT planar information are obtained, including:

[0158] The N frames of echo signals are down-frequency processed to obtain N intermediate frequency signals; the N intermediate frequency signals are then subjected to two-dimensional fast Fourier transform to obtain N 2D-FFT plane information.

[0159] Generally speaking, the frequency of the echo signal received by the radar receiver is relatively high. The sampling frequency needs to be more than twice the signal frequency in order to restore the sampled signal without distortion. If the echo signal received by the receiver is sampled directly, the cost will be very high. Therefore, the echo signal needs to be down-frequency processed to obtain the intermediate frequency signal, which reduces the requirement for the sampling rate.

[0160] For example, when a radar transmitter transmits a target signal, it sends a portion of the target signal to the mixer in the radar. The mixer mixes the target signal and the echo signal to obtain an intermediate frequency signal containing target information, such as the target's range and velocity. Each frame of echo signal may include K chirp signals. Each chirp signal is sampled to obtain M equally spaced sampling points. An M-point range-dimensional FFT is performed on each of the M sampled chirp signals to obtain K sets of range-dimensional M-point FFT information. From the K sets of M-point range-dimensional FFT information, K information with the same index value (index value range is 1, 2, ... m ... M) is extracted and subjected to a K-point Doppler FFT to obtain M sets of K-point Doppler FFT information, i.e., 2D-FFT planar information.

[0161] It is understandable that each frame of echo signal can be processed to obtain a 2D-FFT planar information.

[0162] In this embodiment, N frames of echo signals are processed to obtain N 2D-FFT plane information, so that the interference signal can be judged based on the N 2D-FFT plane information. This allows the interference signal to be judged after the echo signal is processed into 2D-FFT plane information, which does not have high real-time requirements.

[0163] For example, Figure 8 A schematic diagram of a framework for obtaining 2D-FFT planar information is shown. For example... Figure 8 As shown, it includes:

[0164] The received linear frequency modulated signal is processed by 2D-FFT to obtain 2D-FFT planar information. This step is the same as or similar to steps S402 to S403 above, and will not be described again here.

[0165] Figure 9 This is a schematic diagram of the structure of an interference signal detection device provided in an embodiment of this application. Figure 9 As shown, the interference signal detection device 90 includes: a transmitting module 901, a receiving module 902, a first determining module 903, a calculating module 904, and a second determining module 905.

[0166] Transmitting module 901 is used to transmit target signals based on radar.

[0167] The receiving module 902 is used to receive N frames of echo signals, which are the signals returned after the target signal is reflected, where N is an integer greater than 1.

[0168] The first determining module 903 is used to obtain N 2D-FFT plane information based on N frames of echo signals, wherein any 2D-FFT plane information includes power information corresponding to distance and velocity.

[0169] The calculation module 904 is used to calculate the cumulative power information of the sampling points along the velocity dimension of M distance gates in any 2D-FFT plane information for any one of the N 2D-FFT plane information. The distance gate is a distance range, the M distance gates are consecutive, and M is an integer greater than 1.

[0170] The second determining module 905 is used to determine the signal that is interfered with in the N frames of echo signals based on the accumulated power information corresponding to the M distance gates.

[0171] Optionally, the second determining module 905 is specifically used for:

[0172] For any first and second frame echo signals in N frames of echo signals, calculate the difference in accumulated power information of the first and second frame echo signals in the range gate with the same index value, respectively, to obtain L absolute values ​​of the difference, where L is an integer greater than 1 and less than or equal to M; when there is a target difference absolute value greater than a first threshold among the L absolute values ​​of the difference, determine that the echo signal with larger accumulated power information in the target range gate in the first and second frame echo signals is the signal that has been interfered with; the target range gate is the range gate used to calculate the target difference absolute value.

[0173] Optionally, the first frame echo signal is the signal received before the second frame echo signal, and the interference signal detection device 90 further includes:

[0174] The judgment module is used to disable the anti-interference mechanism if the first frame echo signal is an interfered signal, and to activate the anti-interference mechanism if the second frame echo signal is an interfered signal.

[0175] Optionally, the second determining module 905 is specifically used for:

[0176] For any third and fourth frame echo signals in N frames of echo signals, calculate the power difference between the third and fourth frame echo signals in the first distance gate to obtain the first absolute value of the difference. The first distance gate is any one of M distance gates. When the first absolute value of the difference is greater than the first threshold, the echo signal with the larger accumulated power information when calculating the first distance gate in the first and second frame echo signals is determined to be the signal that has been interfered with.

[0177] Optionally, the second determining module 905 is specifically used for:

[0178] If any of the accumulated power information corresponding to the M distance gates of the fifth frame echo signal in the N-frame echo signal is greater than the second threshold, the fifth frame echo signal is determined to be a signal subject to interference.

[0179] Optionally, the first determining module 903 is specifically used to perform down-frequency processing on the N frames of echo signals to obtain N intermediate frequency signals; and to perform two-dimensional fast Fourier transform on the N intermediate frequency signals to obtain N 2D-FFT plane information.

[0180] Optionally, the radar is a millimeter-wave radar.

[0181] The interference signal detection device provided in this application embodiment can be used to execute the above method embodiment. Its implementation principle and technical effect are similar, and will not be described again here.

[0182] Figure 10 This is a schematic diagram of the structure of an interference signal detection device provided in an embodiment of this application. Figure 10 As shown, the interference signal detection device 1000 provided in this application embodiment includes at least one processor 1001 and a memory 1002. The interference signal detection device 1000 also includes a communication component 1003. The processor 1001, memory 1002, and communication component 1003 are connected via a bus 1004.

[0183] In the specific implementation process, at least one processor 1001 executes computer execution instructions stored in memory 1002, causing at least one processor 1001 to execute the interference signal detection method executed by the interference signal detection device 1000 as described above.

[0184] The specific implementation process of processor 1001 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0185] In the above Figure 10In the illustrated embodiments, it should be understood that the processor 1001 can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules in the processor. The memory 602 may include high-speed random access memory (RAM), and may also include non-volatile memory (NVM), such as at least one disk storage device, and may also be a USB flash drive, external hard drive, read-only memory, disk, or optical disk, etc.

[0186] This application embodiment also provides a storage medium storing computer-executable instructions. When these computer-executable instructions are executed by a processor, they implement the aforementioned interference signal detection method. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random-Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The storage medium can be any available medium accessible by a general-purpose or special-purpose computer.

[0187] An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Alternatively, the storage medium can be an integral part of the processor. Both the processor and the storage medium can reside in an application-specific integrated circuit (ASIC). Alternatively, the processor and storage medium can exist as discrete components in an electronic device or host device.

[0188] This application also provides a program product, such as a computer program, which, when executed by a processor, implements the interference signal detection method covered by this application.

[0189] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0190] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them. Although the embodiments of this application have 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 or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for detecting interference signals, characterized in that, When applied to LFMCW radar, the method includes: Based on radar-transmitted target signals; Receive N frames of echo signals, wherein the N frames of echo signals are the signals returned after the target signal is reflected; where N is an integer greater than 1; each frame of echo signal includes multiple chirp signals; Based on the N frames of echo signals, N 2D-FFT plane information are obtained, and each of the 2D-FFT plane information includes power information corresponding to distance and velocity; For any one of the N 2D-FFT planar information, calculate the cumulative power information of M distance gates at the sampling points along the velocity dimension in that 2D-FFT planar information, where each distance gate is a distance range and the M distance gates are consecutive; where M is an integer greater than 1. Based on the accumulated power information corresponding to the M distance gates, determine the signal that is interfered with in the N frames of echo signals; The step of determining the interfered signals in the N frames of echo signals based on the accumulated power information corresponding to the M distance gates includes: Based on the accumulated power information corresponding to the M distance gates, the signal that is interfered with in the N frame echo signal is determined by comparing the difference in accumulated power of the same distance gate between different frames.

2. The method according to claim 1, characterized in that, The step of determining the interfered signals in the N frames of echo signals based on the accumulated power information corresponding to the M distance gates includes: For any first frame echo signal and second frame echo signal in the N frames of echo signals, calculate the difference of the accumulated power information of the first frame echo signal and the second frame echo signal in the distance gate with the same index value, and obtain L absolute values ​​of the difference; where L is an integer greater than 1 and less than or equal to M; When there is a target difference absolute value among the L difference absolute values ​​that is greater than the first threshold, it is determined that the echo signal with larger accumulated power information in the target range gate in the first frame echo signal and the second frame echo signal is the signal that has been interfered with; the target range gate is the range gate used to calculate the target difference absolute value.

3. The method according to claim 2, characterized in that, The first frame echo signal is a signal received before the second frame echo signal, and the method further includes: If the first frame echo signal is a interfered signal, disable the anti-interference mechanism; If the second frame echo signal is a interfered signal, the anti-interference mechanism is activated.

4. The method according to claim 1, characterized in that, The step of determining the interfered signals in the N frames of echo signals based on the accumulated power information corresponding to the M distance gates includes: For any third and fourth frame echo signals in the N frames of echo signals, calculate the power difference between the third and fourth frame echo signals in the first distance gate to obtain the absolute value of the first difference. The first distance gate is any one of the M distance gates. When the absolute value of the first difference is greater than the first threshold, the echo signal with the larger accumulated power information when calculating the first distance gate in the third frame echo signal and the fourth frame echo signal is determined to be the signal that has been interfered with.

5. The method according to claim 1, characterized in that, The step of determining the interfered signal in the N frames of echo signals based on the accumulated power information corresponding to the M distance gates further includes: If any of the accumulated power information corresponding to the M distance gates of the fifth echo signal in the N-frame echo signals exceeds the second threshold, the fifth echo signal is determined to be a signal subject to interference.

6. The method according to any one of claims 1-5, characterized in that, The step of obtaining N 2D-FFT planar information based on the N frames of echo signals includes: The N frames of echo signals are down-frequency processed to obtain N intermediate frequency signals; The N intermediate frequency signals are subjected to two-dimensional fast Fourier transform to obtain the N 2D-FFT plane information.

7. The method according to claim 6, characterized in that, The radar in question is a millimeter-wave radar.

8. An interference signal detection device, applied in LFMCW radar, characterized in that, include: The transmission module is used to transmit target signals based on radar. The receiving module is used to receive N frames of echo signals, which are the signals returned after the target signal is reflected; where N is an integer greater than 1; each frame of echo signal includes multiple chirp signals; The first determining module is used to obtain N 2D-FFT plane information based on the N frames of echo signals, wherein each of the 2D-FFT plane information includes power information corresponding to distance and velocity; The calculation module is used to calculate, for any one of the N 2D-FFT plane information, the cumulative power information of M distance gates along the velocity dimension in any one of the 2D-FFT plane information, where the distance gate is a distance range and the M distance gates are consecutive; where M is an integer greater than 1; The second determining module is used to calculate the difference in accumulated power information between any two echo signals in the N frames of echo signals at at least one distance gate with the same index value, and obtain at least one absolute value of the difference; when there is a target absolute value of difference greater than a first threshold among the at least one absolute value of difference, it is determined that the echo signal with larger accumulated power information in the target distance gate corresponding to the target absolute value of difference is an interfered signal; or, when there is a case where the accumulated power information corresponding to the M distance gates of the fifth frame of echo signals in the N frames of echo signals is greater than a second threshold, it is determined that the fifth frame of echo signal is an interfered signal, and the fifth frame of echo signal is any frame of echo signal in the N frames of echo signals.

9. A method for detecting interference signals, characterized in that, When applied to an FMCW sensor, the method includes: Perform 2D-FFT processing on the echo signal to obtain at least two frames of distance-velocity data; For any frame of range-velocity data, select at least a portion of the range gates, and accumulate the energy of each range gate along the velocity dimension to obtain the accumulated energy value of each range gate; and The difference between the energy accumulation values ​​between the same index value and the distance gate of any two frames of distance-velocity data is obtained to determine whether the echo signal corresponding to each frame of distance-velocity data is interfered with.

10. The method according to claim 9, characterized in that, The step of obtaining the difference in energy accumulation between the same index value and the distance gate of any two frames of distance-velocity data to determine whether the echo signal corresponding to each frame of distance-velocity data is interfered with includes: The energy accumulation value of the distance gate at the predetermined index value in the first frame of distance-velocity data is determined as the first energy accumulation value; The energy accumulation value of the distance gate, which is also the predetermined index value, in the second frame distance-velocity data is determined as the second energy accumulation value; The difference is obtained by subtracting the second energy accumulation value from the first energy accumulation value. If the absolute value of the difference is greater than a preset threshold and the difference is positive, then the echo signal corresponding to the distance-velocity data of the first frame is determined to be an interfered signal and the echo signal corresponding to the distance-velocity data of the second frame is determined to be an undisturbed signal. If the absolute value of the difference is greater than the preset threshold and the difference is negative, then the echo signal corresponding to the distance-velocity data of the second frame is determined to be an interfered signal and the echo signal corresponding to the distance-velocity data of the first frame is an undisturbed signal. If the absolute value of the difference is less than or equal to the preset threshold, then it is determined that the echo signal corresponding to the distance-velocity data of the first frame and the echo signal corresponding to the distance-velocity data of the second frame are both undisturbed signals. The preset threshold is greater than the threshold for CFAR processing of the echo signal.

11. The method according to claim 10, characterized in that, When it is determined that the echo signal corresponding to the first frame distance-velocity data and the echo signal corresponding to the second frame distance-velocity data are both undisturbed signals, if the first energy accumulation value is greater than a preset average threshold, it can be determined that the echo signal corresponding to the first frame distance-velocity data contains target information.

12. An interference signal detection device, characterized in that, include: At least one processor and memory; The memory stores computer-executed instructions; The at least one processor executes computer execution instructions stored in the memory, causing the at least one processor to perform the method as described in any one of claims 1-7 or 9-11.

13. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, implement the method as described in any one of claims 1-7 or 9-11.

14. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the method as described in any one of claims 1-7 or 9-11.

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