A method and device for determining a moving trajectory

Abstract

The present application provides a method and device for determining a moving trajectory, which are used to improve the accuracy and stability of determining a moving trajectory. In the present application, the difference frequency signal is processed by three-dimensional FFT to generate an RA heat map; after determining the reflection point of the target contained in the RA heat map, the moving trajectory of the target is determined in combination with the behavior trajectory of the target in the STFT heat map, and the STFT heat map is obtained by processing the difference frequency signal through STFT transformation; wherein, the difference frequency signal is determined based on the transmitted interlaced frequency modulation sequence wave and the received reflected interlaced frequency modulation sequence wave. In the present application, an interlaced frequency modulation sequence wave is used to determine the difference frequency signal, and the difference frequency signal is subjected to signal processing through FFT transformation and STFT transformation to achieve multi-target resolution and improve the accuracy and stability of determining the moving trajectory.

Description

Technical Field

[0001] The present application relates to the field of communication technology and provides a method and device for determining a movement trajectory. Background Art

[0002] With the development of wireless signals, indoor trajectory tracking is applied to various scenarios. At present, infrared technology, ultrasonic positioning, wifi (wireless fidelity) and other technologies are mainly used to achieve trajectory tracking. These technologies all determine the distance through RSSI (Received Signal Strength Indicator). Due to environmental factors, the signal will be reflected multiple times, which will cause multipath interference and signal attenuation, thus seriously affecting the precision and accuracy of determining the moving trajectory. Summary of the invention

[0003] The embodiments of the present application provide a method and device for determining a movement trajectory, so as to improve the accuracy and stability of determining the movement trajectory.

[0004] In a first aspect, an embodiment of the present application provides a method for determining a movement trajectory, the method comprising:

[0005] The difference frequency signal is processed by three-dimensional FFT (Fast Fourier Transform) to generate RA (Range-Angel) heat map;

[0006] After determining the reflection points of the target contained in the RA heat map, the target's movement trajectory is determined by combining the target's behavior trajectory in the STFT (Short-Time Fourier Transform) heat map. The STFT heat map is obtained by processing the difference frequency signal through STFT transformation.

[0007] The difference frequency signal is determined based on the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave.

[0008] In the present application, the difference frequency signal is determined according to the transmitted interlaced frequency modulation sequence wave and the received reflected interlaced frequency modulation sequence wave, and the difference frequency signal is subjected to a three-dimensional FFT transform to generate an RA heat map. The reflection point of the target can be detected in the RA heat map, and combined with the behavior trajectory of the target in the STFT heat map, the STFT heat map is obtained by processing the difference frequency signal through the STFT transform, and depicts the movement trajectory of the target; in the present application, an interlaced frequency modulation sequence wave is used to determine the difference frequency signal, and the difference frequency signal is subjected to signal processing through FFT transform and STFT transform to achieve multi-target resolution capability, improve the accuracy and stability of determining the movement trajectory, and the waveform implementation is simple.

[0009] In a possible implementation, the three-dimensional FFT includes: distance FFT, velocity FFT and angle FFT;

[0010] The difference frequency signal is processed by three-dimensional FFT to generate a distance-angle RA heat map, including:

[0011] The difference frequency signal is processed by distance FFT to obtain a one-dimensional distance spectrum;

[0012] Perform velocity FFT transformation on the one-dimensional distance spectrum to obtain a two-dimensional velocity spectrum;

[0013] The maximum Doppler peak of the two-dimensional velocity spectrum is transformed by angle FFT, and the results of the angle FFT transformation are connected to generate the RA heat map.

[0014] In the present application, the difference frequency signal is processed by distance FFT to obtain a one-dimensional distance spectrum, and then a speed FFT transform is performed on the basis of the one-dimensional distance spectrum to obtain a two-dimensional speed spectrum, and an angle FFT transform is performed on the basis of the two-dimensional speed spectrum, and the results after the angle FFT transform are connected to form an RA heat map, and a method for generating the RA heat map is given; and in this process, the distance, speed and angle of the target can be determined. Therefore, when determining the moving trajectory of the target, the moving trajectory of the target can be determined in combination with the determined distance, speed and angle of the target, which can greatly improve the accuracy and stability.

[0015] In a possible implementation, after performing a velocity FFT transformation on the one-dimensional range spectrum and before performing an angle FFT transformation on the maximum Doppler peak of the two-dimensional velocity spectrum, the time window is moved on the two-dimensional velocity spectrum according to a preset step value;

[0016] Each time the time window is moved, it is determined whether the amplitude at the position of the time window is greater than the preset threshold value of the time window;

[0017] If the amplitude at the time window position is greater than the preset threshold value of the time window, the two-dimensional velocity spectrum corresponding to the current time window is selected as the two-dimensional velocity spectrum used when performing the angle FFT transformation.

[0018] In the present application, a time window sliding mode is adopted. When it is determined that the amplitude of the position of the time window is greater than the preset threshold value of the time window, it is determined that there is a target at the current position of the time window, and the two-dimensional velocity spectrum corresponding to the current time window is selected as the two-dimensional velocity spectrum used when performing the angle FFT transformation, so as to effectively distinguish the target and improve the detection efficiency when detecting the reflection point of the target in the RA heat map determined according to the two-dimensional velocity spectrum.

[0019] In a possible implementation, before performing velocity FFT transformation on the one-dimensional range spectrum to obtain the two-dimensional velocity spectrum, Wiener filtering is used to process the one-dimensional range spectrum to filter out noise in the one-dimensional range spectrum.

[0020] In this application, the noise in the signal is processed to improve the accuracy.

[0021] In a possible implementation, after determining the reflection point of the target included in the RA heat map, the movement trajectory of the target is determined in combination with the behavior trajectory in the STFT heat map of the target, including:

[0022] Combined with the behavior trajectory of the target in the STFT heat map, the reflection points of the target contained in the RA heat map are connected according to the attributes of the reflection points to generate the target's movement trajectory.

[0023] In the present application, since different objects have different behavioral characteristics during movement, that is, different behavioral trajectories, it is necessary to determine the target's behavioral trajectory when determining the target's moving trajectory. However, behavioral characteristics alone cannot determine the moving trajectory, so each position of the target during movement, that is, the reflection point, must be determined. Since the same environment contains multiple stationary or moving objects, but the moving distance, moving speed, and moving angle of each object during movement are different, that is, the properties of the target's reflection point are different. Therefore, in the process of determining the target's moving trajectory, the properties of the target's reflection point are also required. The above specifically provides connecting the reflection points according to the target's behavioral trajectory and the properties of the determined target's reflection point to generate the target's moving trajectory, thereby improving the accuracy and stability of determining the moving trajectory.

[0024] In a second aspect, an embodiment of the present application provides a device for determining a movement trajectory, the device comprising: at least one processing unit and at least one storage unit, wherein the storage unit stores a program code, and when the program code is executed by the processing unit, the processing unit is specifically used to:

[0025] The difference frequency signal is processed by three-dimensional fast Fourier transform FFT to generate a distance-angle RA heat map; after determining the reflection point of the target contained in the RA heat map, the moving trajectory of the target is determined by combining the behavior trajectory in the short-time Fourier transform STFT heat map of the target. The STFT heat map is obtained by processing the difference frequency signal through STFT transformation;

[0026] The difference frequency signal is determined based on the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave.

[0027] In a possible implementation, the three-dimensional FFT includes: distance FFT, velocity FFT and angle FFT;

[0028] The processing unit is specifically used for:

[0029] The difference frequency signal is processed by distance FFT to obtain a one-dimensional distance spectrum;

[0030] Perform velocity FFT transformation on the one-dimensional distance spectrum to obtain a two-dimensional velocity spectrum;

[0031] The maximum Doppler peak of the two-dimensional velocity spectrum is transformed by angle FFT, and the results of the angle FFT transformation are connected to generate the RA heat map.

[0032] In a possible implementation manner, the processing unit is further configured to:

[0033] After performing a velocity FFT transformation on the one-dimensional range spectrum and before performing an angle FFT transformation on the maximum Doppler peak of the two-dimensional velocity spectrum, the time window is moved on the two-dimensional velocity spectrum according to a preset step value;

[0034] Each time the time window is moved, it is determined whether the amplitude at the position of the time window is greater than the preset threshold value of the time window;

[0035] If the amplitude at the time window position is greater than the preset threshold value of the time window, the two-dimensional velocity spectrum corresponding to the current time window is selected as the two-dimensional velocity spectrum used when performing the angle FFT transformation.

[0036] In a possible implementation manner, the processing unit is further configured to:

[0037] Before performing velocity FFT transformation on the one-dimensional range spectrum to obtain the two-dimensional velocity spectrum, the one-dimensional range spectrum is processed by Wiener filtering to filter out the noise in the one-dimensional range spectrum.

[0038] In a possible implementation manner, the processing unit is specifically configured to:

[0039] Combined with the behavior trajectory of the target in the STFT heat map, the reflection points of the target contained in the RA heat map are connected according to the attributes of the reflection points to generate the target's movement trajectory.

[0040] In a third aspect, an embodiment of the present application provides a device for determining a movement trajectory, the device comprising: a generating module and a determining module, wherein:

[0041] The generation module is used to: process the difference frequency signal through three-dimensional fast Fourier transform FFT to generate a distance-angle RA heat map;

[0042] The determination module is used to: determine the moving trajectory of the target after determining the reflection point of the target contained in the RA heat map, combined with the behavior trajectory in the short-time Fourier transform STFT heat map of the target, where the STFT heat map is obtained by processing the difference frequency signal through STFT transformation;

[0043] The difference frequency signal is determined based on the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave.

[0044] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores computer instructions. When the computer instructions are executed by a processor, the method for determining a movement trajectory provided in an embodiment of the present application is implemented.

[0045] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0047] Figure 1 A flow chart of a method for determining a movement trajectory provided in an embodiment of the present application;

[0048] Figure 2 A flow chart of an overall method for determining a movement trajectory provided in an embodiment of the present application;

[0049] Figure 3 A structural diagram of a device for determining a moving trajectory provided in an embodiment of the present application;

[0050] Figure 4 A structural diagram of a device for determining a movement trajectory provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] The application scenarios described in the embodiments of the present invention are intended to more clearly illustrate the technical solutions of the embodiments of the present invention, and do not constitute a limitation on the technical solutions provided by the embodiments of the present invention. It is known to those skilled in the art that with the emergence of new application scenarios, the technical solutions provided by the embodiments of the present invention are also applicable to similar technical problems. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0052] The following is a brief introduction to the design concept of the embodiments of the present application.

[0053] With the development of wireless signals, determining the moving trajectory of targets indoors has been applied to various scenarios. Infrared technology, wifi, etc. are mainly used in the prior art. However, the existing methods for determining moving trajectories have more or less disadvantages. For example: wifi and infrared technology are not accurate enough, cannot segment targets, have large positioning errors, and are greatly affected by multipath interference; dual-frequency continuous wireless waves, the time domain threshold setting method is not applicable to the frequency domain, and the target will be out of a certain range. There will be speed ambiguity, resulting in speed measurement errors; the SOF signal (frame start signal) interval on the USB bus (Universal Serial Bus) is used for timing, and the process is complicated.

[0054] In view of this, an embodiment of the present application provides a method and device for determining a moving trajectory, which is mainly based on radio waves to determine the moving trajectory of a target indoors. The present application adopts an interlaced frequency modulation sequence waveform, which is transformed by STFT (Short-TimeFourier Transform) and FFT (Fast Fourier Transform), and Wiener filtering, which can effectively suppress the speed ambiguity problem, and can not only extract distance, but also speed and angle. The accuracy and stability of determining the moving trajectory are greatly improved. And the target can be accurately segmented through a heat map.

[0055] In order to make the purpose, technical solution and beneficial effects of this application clearer, the technical solution in the embodiment of this application will be clearly and completely described below in conjunction with the drawings in the embodiment of this application. Obviously, the described embodiment is only a part of the embodiment of this application, not all the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0056] like Figure 1 As shown, a flow chart of a method for determining a movement trajectory provided in an embodiment of the present application includes the following steps:

[0057] Step 101, processing the difference frequency signal through three-dimensional FFT to generate an RA heat map.

[0058] In the present application, the difference frequency signal is determined based on the interleaved frequency modulation sequence waves continuously transmitted by multiple antennas and the received reflected interleaved frequency modulation sequence waves.

[0059] Specifically, the antenna transmits an interleaved frequency modulation sequence wave. When the interleaved frequency modulation sequence wave encounters an obstacle, it will be reflected and reflected back to the antenna end. Therefore, after receiving the reflected interleaved frequency modulation sequence wave, the antenna end determines that the difference between the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave is the difference frequency signal.

[0060] The obstacles include the ground and the target to be detected. The target to be detected can be a pedestrian or any moving object. Each obstacle can reflect, so there are multiple reflection points.

[0061] After determining the difference frequency signal, since the characteristics of the signal cannot be determined in the time domain, but the characteristics of the signal can be easily obtained in the frequency domain, it is very important to transform the difference frequency signal from the time domain to the frequency domain.

[0062] In this application, the difference frequency signal is mainly processed by three-dimensional FFT transformation.

[0063] Among them, the three-dimensional FFT includes: distance FFT, velocity FFT and angle FFT.

[0064] In the present application, firstly, a distance FFT transform is performed on the difference frequency signal to obtain a one-dimensional distance spectrum corresponding to the difference frequency signal;

[0065] It should be noted that the one-dimensional distance spectrum diagram can also be called a distance-pulse diagram.

[0066] In the present application, when the difference frequency signals are processed, the difference frequency signals with the same frequency modulation period are subjected to distance FFT transformation in chronological order.

[0067] After obtaining the one-dimensional distance spectrum diagram, the spectrum peak position in the two-dimensional spectrum diagram is determined, and the distance of the reflection point is determined according to the spectrum peak position.

[0068] In this application, the distance of the reflection point is calculated by the following formula:

[0069] d = cf / 2S

[0070] Where d represents distance, f represents frequency, S represents frequency modulation slope, and C represents the speed of light.

[0071] After determining the one-dimensional range spectrum, a velocity FFT transformation is performed on the basis of the one-dimensional range spectrum to obtain a two-dimensional velocity spectrum;

[0072] It should be noted that the two-dimensional velocity spectrum can also be called a range-Doppler diagram.

[0073] After determining the two-dimensional velocity spectrum, the maximum Doppler peak in the two-dimensional velocity spectrum is extracted, and the peak is subjected to angle FFT transformation. The results of the angle FFT transformation are connected to generate the RA heat map.

[0074] It should be noted that, in the process of performing the velocity FFT transformation, the velocity of the reflection point can be determined; and, in the process of performing the angle FFT transformation, the angle of the reflection point can be determined.

[0075] Among them, the RA heat map includes positions where the color brightness is greater than the brightness threshold. Positions with relatively large color brightness indicate that the reflection amplitude is relatively large, so static objects and moving objects can be distinguished, that is, the reflection point at the position with relatively large color brightness is the reflection point of the target.

[0076] Since the two-dimensional velocity spectrum is obtained by performing velocity FFT transformation on the one-dimensional range spectrum, and the one-dimensional range spectrum is obtained based on the difference frequency signal, the difference frequency signal not only contains the target to be detected, but also includes noise and ground clutter. Therefore, in order to improve the detection efficiency of the target in the signal, the present application determines the two-dimensional velocity spectrum used when performing the angle FFT transformation before determining the RA heat map of the reflection point that can detect the target, that is, before performing the angle FFT transformation on the maximum Doppler peak of the two-dimensional velocity spectrum.

[0077] In the present application, a two-dimensional velocity spectrum used in performing angle FFT transformation is determined by adopting a time window sliding mode.

[0078] Optionally, a time window sliding mode is used to determine the two-dimensional velocity spectrum used when performing the angle FFT transform, as follows:

[0079] The time window is moved on the two-dimensional velocity spectrum according to the preset step value. Each time the time window is moved, it is determined whether the amplitude at the time window position is greater than the preset threshold value of the time window; if the amplitude at the time window position is greater than the preset threshold value of the time window, it is determined that there is a target at the current time window position, and the two-dimensional velocity spectrum corresponding to the current time window is selected as the two-dimensional velocity spectrum used for angle FFT transformation. If the amplitude at the time window position is less than the preset threshold value of the time window, it means that there is no target.

[0080] Therefore, this application adopts the time window sliding mode to accurately segment the target so as to detect the target more clearly.

[0081] Step 102, after determining the reflection point of the target included in the RA heat map, the movement trajectory of the target is determined in combination with the behavior trajectory in the STFT heat map of the target.

[0082] The attributes of the reflection point include distance, speed, and angle, which are determined in distance FFT transformation, speed FFT transformation, and angle FFT transformation, respectively.

[0083] And because the distance, speed and angle of different targets in the process of movement are regular, the reflection point of the target can be determined from multiple reflection points according to the properties of the reflection point.

[0084] After determining the reflection points of the target, combined with the behavior trajectory in the target's STFT heat map, the reflection points of the target are connected according to the attributes of the reflection points, and the generated curve is the moving trajectory of the target.

[0085] The STFT heat map is obtained by processing the difference frequency signal through STFT transformation. Specifically, it is obtained by performing STFT transformation on the one-dimensional distance spectrum corresponding to the difference frequency signal through distance FFT transformation. The STFT heat map is a time-frequency image that plots the spectrum as a function of time.

[0086] In a possible implementation, before determining the RA heat map based on the one-dimensional distance spectrum corresponding to the difference frequency signal and determining the STFT heat map based on the one-dimensional distance spectrum corresponding to the difference frequency signal, it is also necessary to perform Wiener filtering on the one-dimensional distance spectrum to filter out the noise in the one-dimensional distance spectrum so as to improve the accuracy of target detection.

[0087] like Figure 2 As shown, it is a flow chart of an overall method for data collection provided by an embodiment of the present invention, comprising the following steps:

[0088] Step 200, receiving a reflected interleaved frequency modulation sequence wave;

[0089] Step 201, taking the difference between the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave as a difference frequency signal;

[0090] Step 202, processing the difference frequency signals of all frequency modulation cycles in chronological order through range FFT transformation to obtain a one-dimensional range spectrum corresponding to the difference frequency signals;

[0091] Step 203, performing Wiener filtering on the one-dimensional range spectrum to filter out noise in the one-dimensional range spectrum to obtain a target one-dimensional range spectrum;

[0092] Step 204, performing STFT transformation on the target one-dimensional range spectrum to obtain an STFT heat map;

[0093] Step 205, performing a velocity FFT transformation on the target one-dimensional range spectrum to obtain a two-dimensional velocity spectrum;

[0094] Step 206, moving the time window on the two-dimensional velocity spectrum according to a preset step value, and when the amplitude at the time window position is greater than a preset threshold value of the time window, selecting the two-dimensional velocity spectrum corresponding to the current time window as the target two-dimensional velocity spectrum used for angle FFT transformation;

[0095] Step 207, performing an angle FFT transformation on the maximum Doppler peak of the target two-dimensional velocity spectrum, and connecting the results of the angle FFT transformation to form an RA heat map;

[0096] Step 208 , combining the behavior trajectory of the target in the STFT heat map, connecting the reflection points of the target in the RA heat map according to the attributes of the reflection points, and generating the movement trajectory of the target.

[0097] It should be noted that step 204 is parallel to steps 205 to 207, so step 204 can execute the implementation method of performing speed FFT transformation on the target one-dimensional distance spectrum to obtain a two-dimensional speed spectrum, step 205 executes the implementation method of the above step 206, step 206 can execute the implementation method of the above step 207, and step 207 can execute the implementation method of the above step 204, which will not be repeated here.

[0098] In summary, the method for determining the moving trajectory provided by the embodiment of the present application adopts an interlaced frequency modulation sequence wave, and the waveform is relatively simple to implement; at the same time, the difference frequency signal determined according to the interlaced frequency modulation sequence wave is subjected to STFT transformation, FFT transformation and Wiener filtering, that is, data processing is performed on the difference frequency signal, so that not only the distance can be extracted, but also the speed and angle can be extracted, thereby improving the accuracy and stability of determining the moving trajectory. At the same time, the time window sliding method is used in the present application to effectively distinguish the target.

[0099] Based on the same inventive concept, a device for determining a moving trajectory is also provided in an embodiment of the present invention. Since the device corresponds to the device corresponding to the device for determining a moving trajectory in an embodiment of the present invention, and the principle of solving the problem by the device is similar to the principle of the method, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0100] like Figure 3 As shown, it is a structural diagram of a device for determining a moving trajectory provided by an embodiment of the present invention, and the device includes: at least one processing unit 300 and at least one storage unit 301, wherein the storage unit 301 stores a program code, and when the program code is executed by the processing unit 300, the processing unit 300 is specifically used to:

[0101] The difference frequency signal is processed by three-dimensional FFT to generate the RA heat map;

[0102] After determining the reflection points of the target contained in the RA heat map, the moving trajectory of the target is determined by combining the behavior trajectory in the STFT heat map of the target. The STFT heat map is obtained by processing the difference frequency signal through STFT transformation;

[0103] The difference frequency signal is determined based on the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave.

[0104] In a possible implementation, the three-dimensional FFT includes: distance FFT, velocity FFT and angle FFT;

[0105] The processing unit 300 is specifically used for:

[0106] The difference frequency signal is processed by distance FFT to obtain a one-dimensional distance spectrum;

[0107] Perform velocity FFT transformation on the one-dimensional distance spectrum to obtain a two-dimensional velocity spectrum;

[0108] The maximum Doppler peak of the two-dimensional velocity spectrum is transformed by angle FFT, and the results of the angle FFT transformation are connected to generate the RA heat map.

[0109] In a possible implementation, the processing unit 300 is further configured to:

[0110] After performing a velocity FFT transformation on the one-dimensional range spectrum and before performing an angle FFT transformation on the maximum Doppler peak of the two-dimensional velocity spectrum, the time window is moved on the two-dimensional velocity spectrum according to a preset step value;

[0111] Each time the time window is moved, it is determined whether the amplitude at the position of the time window is greater than the preset threshold value of the time window;

[0112] If the amplitude at the time window position is greater than the preset threshold value of the time window, the two-dimensional velocity spectrum corresponding to the current time window is selected as the two-dimensional velocity spectrum used when performing the angle FFT transformation.

[0113] In a possible implementation, the processing unit 300 is further configured to:

[0114] Before performing velocity FFT transformation on the one-dimensional range spectrum to obtain the two-dimensional velocity spectrum, the one-dimensional range spectrum is processed by Wiener filtering to filter out the noise in the one-dimensional range spectrum.

[0115] In a possible implementation, the processing unit 300 is specifically configured to:

[0116] Combined with the behavior trajectory in the target's short-time Fourier transform (STFT) heat map, the reflection points of the target contained in the RA heat map are connected according to the attributes of the reflection points to generate the target's movement trajectory.

[0117] In a possible implementation, the attributes of the reflection point include distance, speed, and angle, wherein the distance is obtained in distance FFT transformation, the speed is obtained in speed FFT transformation, and the angle is obtained in angle FFT transformation.

[0118] In a possible implementation, the present application also provides a device for determining a movement trajectory. Figure 4 As shown, it is a structural diagram of a device for determining a moving trajectory provided by an embodiment of the present invention, and the device includes: a generating module 401 and a determining module 402, wherein:

[0119] The generating module 401 is used to: process the difference frequency signal through a three-dimensional fast Fourier transform FFT to generate a distance-angle RA heat map;

[0120] The determination module 402 is used to: after determining the reflection point of the target included in the RA heat map, determine the moving trajectory of the target in combination with the behavior trajectory in the short-time Fourier transform STFT heat map of the target, where the STFT heat map is obtained by processing the difference frequency signal through STFT transformation;

[0121] The difference frequency signal is determined based on the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave.

[0122] In a possible implementation, the three-dimensional FFT includes: distance FFT, velocity FFT and angle FFT;

[0123] The generation module 401 is specifically used for:

[0124] The difference frequency signal is processed by distance FFT to obtain a one-dimensional distance spectrum;

[0125] Perform velocity FFT transformation on the one-dimensional distance spectrum to obtain a two-dimensional velocity spectrum;

[0126] The maximum Doppler peak of the two-dimensional velocity spectrum is transformed by angle FFT, and the results of the angle FFT transformation are connected to generate the RA heat map.

[0127] In a possible implementation, the generating module 401 is further configured to:

[0128] After performing a velocity FFT transformation on the one-dimensional range spectrum and before performing an angle FFT transformation on the maximum Doppler peak of the two-dimensional velocity spectrum, the time window is moved on the two-dimensional velocity spectrum according to a preset step value;

[0129] Each time the time window is moved, it is determined whether the amplitude at the position of the time window is greater than the preset threshold value of the time window;

[0130] If the amplitude at the time window position is greater than the preset threshold value of the time window, the two-dimensional velocity spectrum corresponding to the current time window is selected as the two-dimensional velocity spectrum used when performing the angle FFT transformation.

[0131] In a possible implementation, the generating module 401 is further configured to:

[0132] According to the one-dimensional distance spectrum corresponding to the difference frequency signal, before generating the RA heat map, the one-dimensional distance spectrum is processed by Wiener filtering to filter out the noise in the one-dimensional distance spectrum.

[0133] In a possible implementation, the determination module 402 is specifically configured to:

[0134] Combined with the behavior trajectory in the target's short-time Fourier transform (STFT) heat map, the reflection points of the target contained in the RA heat map are connected according to the attributes of the reflection points to generate the target's movement trajectory.

[0135] In a possible implementation, the attributes of the reflection point include distance, speed, and angle, wherein the distance is obtained in distance FFT transformation, the speed is obtained in speed FFT transformation, and the angle is obtained in angle FFT transformation.

[0136] In some possible implementations, the embodiments of the present application further provide a computer-readable storage medium, which includes computer instructions, and when the computer instructions are executed by a processor, the steps of any one of the methods for determining a movement trajectory in the above embodiments are implemented.

[0137] In some possible implementations, various aspects of the method for determining a motion trajectory provided in the present application may also be implemented in the form of a program product, which includes a program code. When the program product is run on a computer device, the program code is used to enable the computer device to perform the steps of any one of the methods for determining a motion trajectory in the above embodiments.

[0138] Among them, the program product can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable signal medium can be, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples (non-exhaustive) 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 disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0139] The program product generated by the channel connection of the embodiment of the present application can adopt a portable compact disk read-only memory (CD-ROM) and include program code, and can be run on a computing device. However, the program product of the present application is not limited to this. In this document, the readable storage medium can be any tangible medium containing or storing a program, which can be used by a command execution system, device or device or used in combination with it.

[0140] The readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, wherein the readable program code is carried. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable signal medium may also be any readable medium other than a readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with a command execution system, apparatus, or device.

[0141] The program code embodied on the readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the foregoing.

[0142] Program code for performing the operations of the present application may 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 may be executed entirely on the user computing device, partially on the user equipment, 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 may be connected to the user computing device via any type of network including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0143] It should be noted that, although several units or subunits of the device are mentioned in the above detailed description, this division is merely exemplary and not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more units described above can be embodied in one unit. Conversely, the features and functions of one unit described above can be further divided into multiple units to be embodied.

[0144] In addition, although the operations of the method of the present application are described in a specific order in the drawings, this does not require or imply that the operations must be performed in this specific order, or that all the operations shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps.

[0145] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0146] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program commands. These computer program commands can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the commands executed by the processor of the computer or other programmable data processing device generate commands for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0147] These computer program commands may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the commands stored in the computer readable memory produce an article of manufacture comprising a command device, the command device implementing the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0148] These computer program commands can also be loaded onto a computer or other programmable data processing device so that a series of operation steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the commands executed on the computer or other programmable device provide the instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0149] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0150] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for determining a movement trajectory, characterized in that: The method includes: The difference frequency signal is processed by three-dimensional fast Fourier transform FFT to generate a distance-angle RA heat map; wherein the difference frequency signal is determined according to the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave; After determining the reflection points of the target contained in the RA heat map, the reflection points of the target are connected according to the attributes of the reflection points in combination with the behavior trajectory in the short-time Fourier transform STFT heat map of the target, and the curve generated by the connection is used as the moving trajectory of the target; wherein the STFT heat map is obtained by processing a one-dimensional distance spectrum through STFT transformation, the one-dimensional distance spectrum is obtained by processing the difference frequency signal through distance FFT transformation, and the STFT heat map is a time-frequency image that plots the spectrum as a function of time.

2. The method according to claim 1, characterized in that The three-dimensional FFT includes: distance FFT, velocity FFT and angle FFT; The difference frequency signal is processed by three-dimensional fast Fourier transform FFT to generate a distance-angle RA heat map, including: Processing the difference frequency signal by means of the distance FFT to obtain a one-dimensional distance spectrum; Performing a velocity FFT transformation on the one-dimensional distance spectrum to obtain a two-dimensional velocity spectrum; Angle FFT transformation is performed on the maximum Doppler peak of the two-dimensional velocity spectrum, and the results of the angle FFT transformation are connected to generate the RA heat map.

3. The method according to claim 2, characterized in that After performing a velocity FFT transformation on the one-dimensional range spectrum and before performing an angle FFT transformation on the maximum Doppler peak of the two-dimensional velocity spectrum, the method further includes: On the two-dimensional velocity spectrum, moving the time window according to a preset step value; Each time the time window is moved, determining whether the amplitude at the position of the time window is greater than a preset threshold value of the time window; If the amplitude at the position of the time window is greater than the preset threshold value of the time window, the two-dimensional velocity spectrum corresponding to the current time window is selected as the two-dimensional velocity spectrum used when performing the angle FFT transformation.

4. The method according to claim 2, characterized in that Before performing a velocity FFT transformation on the one-dimensional distance spectrum to obtain a two-dimensional velocity spectrum, the method further includes: The one-dimensional range spectrum is processed by using Wiener filtering to filter out noise in the one-dimensional range spectrum.

5. A device for determining a movement trajectory, characterized in that: The device includes: at least one processing unit and at least one storage unit, wherein the storage unit stores program codes, and when the program codes are executed by the processing unit, the processing unit is specifically used to: The difference frequency signal is processed by three-dimensional fast Fourier transform FFT to generate a distance-angle RA heat map; wherein the difference frequency signal is determined according to the transmitted interleaved frequency modulation sequence wave and the received reflected interleaved frequency modulation sequence wave; After determining the reflection points of the target contained in the RA heat map, the reflection points of the target are connected according to the attributes of the reflection points in combination with the behavior trajectory in the short-time Fourier transform STFT heat map of the target, and the curve generated by the connection is used as the moving trajectory of the target; wherein the STFT heat map is obtained by processing a one-dimensional distance spectrum through STFT transformation, the one-dimensional distance spectrum is obtained by processing the difference frequency signal through distance FFT transformation, and the STFT heat map is a time-frequency image that plots the spectrum as a function of time.

6. The device according to claim 5, characterized in that The three-dimensional FFT includes: distance FFT, velocity FFT and angle FFT; The processing unit is specifically used for: Processing the difference frequency signal by means of the distance FFT to obtain a one-dimensional distance spectrum; Performing a velocity FFT transformation on the one-dimensional distance spectrum to obtain a two-dimensional velocity spectrum; Angle FFT transformation is performed on the maximum Doppler peak of the two-dimensional velocity spectrum, and the results of the angle FFT transformation are connected to generate the RA heat map.

7. The device according to claim 6, characterized in that The processing unit is also used for: After performing a velocity FFT transformation on the one-dimensional range spectrum and before performing an angle FFT transformation on the maximum Doppler peak of the two-dimensional velocity spectrum, a time window is moved on the two-dimensional velocity spectrum according to a preset step value; Each time the time window is moved, determining whether the amplitude at the position of the time window is greater than a preset threshold value of the time window; If the amplitude at the position of the time window is greater than the preset threshold value of the time window, the two-dimensional velocity spectrum corresponding to the current time window is selected as the two-dimensional velocity spectrum used when performing the angle FFT transformation.

8. The device according to claim 6, characterized in that The processing unit is also used for: Before performing the speed FFT transformation on the one-dimensional range spectrum to obtain the two-dimensional speed spectrum, the one-dimensional range spectrum is processed by using Wiener filtering to filter out noise in the one-dimensional range spectrum.

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