Target detection method and apparatus of radar, terminal, and storage medium

Abstract

A target detection method and apparatus of a radar, a related terminal, and a computer-readable storage medium. The method comprises: enabling a first working mode of a radar, and upon detection of a first-type target, enabling a second working mode of the radar (101); detecting a second-type target within a first preset duration, and upon detection of the second-type target, enabling a third working mode of the radar (102); within a second preset duration, the radar performing multi-dimensional measurement parameter extraction and detecting a third-type target, and upon detection of the third-type target within the second preset duration, enabling a fourth working mode of the radar or controlling the radar to be still in the third working mode (103); and in the fourth working mode, the radar performing target detection in different time windows (104). The method reduces the impact of micro-motion interference on radars and reduces power consumption of radars.

Description

Target detection method and device of radar, terminal and storage medium

[0001] The present application claims priority to the Chinese patent application No. 2024111133903, filed on August 14, 2024, and entitled "Target detection method and device of radar, terminal and storage medium", the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of radar, in particular to a target detection method and device of radar, terminal and storage medium. BACKGROUND

[0003] Radar is an electronic device that uses electromagnetic waves to detect targets and is widely used in various industries, such as terrain measurement, atmospheric monitoring, and unmanned driving. Radar is widely used in the field of intelligent Internet of Things for target perception and judgment. In order to improve the perception experience of the target, the radar device usually extracts multi-dimensional information of the perceived target to make accurate judgments about the existence of the target and accurate measurements of the target parameters.

[0004] In actual use, the applicant found that in a persistent interference scenario, such as a wind continuously blowing an object in the environment or the object continuously vibrating, the radar device is prone to frequently performing high-complexity parameter measurement functions on the environmental interference object, resulting in waste of power consumption of the radar device. SUMMARY

[0005] The embodiments of the present application provide a target detection method and device of radar, terminal and storage medium, which can make the radar enter a later working mode only after passing the anti-interference detection, thereby helping to reduce the influence of various micro-motion interferences in an interference environment and reducing the power consumption of the radar.

[0006] The embodiments of the present application provide a target detection method of radar, comprising:

[0007] Starting a first working mode of the radar, and starting a second working mode of the radar when a first type of target is detected;

[0008] Detecting a second type of target within a first preset time period, and starting a third working mode of the radar when the second type of target is detected;

[0009] Within a second preset time period, the radar performs multi-dimensional measurement parameter extraction to detect a third type of target, and starts a fourth working mode of the radar or controls the radar to remain in the third working mode when the third type of target is detected within the second preset time period, wherein the multi-dimensional measurement parameters include distance, speed, angle, breathing and heartbeat frequency, micro-Doppler, and motion trajectory;

[0010] In the fourth working mode, the radar divides time windows to detect targets, and if the expected target is detected in a time window, the radar enters the next time window to continue detecting whether the expected target exists, the expected target including the first type of target, the second type of target and the third type of target, the first type of target including the second type of target, and the second type of target including the third type of target.

[0011] In an embodiment, after the first working mode of the radar is started, the method further includes:

[0012] periodically transmitting a first frame format probe signal, and detecting the first type of target according to the received signal;

[0013] if the radar is a range radar, generating a range spectrum according to the received signal of each frame, and detecting the first type of target on the range spectrum;

[0014] if the radar is a Doppler radar, generating a velocity spectrum according to the received signal of each frame, and detecting the first type of target on the velocity spectrum.

[0015] In an embodiment, after the second working mode of the radar is started, the method further includes:

[0016] transmitting multiple second frame format probe signals, and performing weighted combination on data with the same sampling point number in all received signals to obtain a combined signal, wherein the transmitted second frame format probe signals are arranged at unequal intervals in time;

[0017] if the radar is a range radar, generating a range spectrum according to the combined signal, and detecting the second type of target on the range spectrum;

[0018] if the radar is a Doppler radar, calculating an energy value of the combined signal, and detecting the second type of target according to a comparison result of the energy value and an energy threshold value.

[0019] In an embodiment, after the second working mode of the radar is started, the method further includes:

[0020] transmitting multiple second frame format probe signals, and performing front-back difference processing on all received signals according to the receiving sequence to obtain multiple difference signals, wherein the transmitted second frame format probe signals are arranged at unequal intervals in time;

[0021] if the radar is a range radar, generating multiple range spectra according to the multiple difference signals, and detecting the second type of target according to a number of targets detected from the multiple range spectra;

[0022] If the radar is a Doppler radar, energy values of the plurality of difference signals are calculated, and a second type of target detection is performed according to a number of energy values exceeding an energy threshold.

[0023] In an embodiment, the radar performs multi-dimensional measurement parameter extraction, including:

[0024] periodically transmitting a third frame format probe signal and receiving a corresponding echo signal;

[0025] If the radar is a ranging radar, a range-velocity spectrum is generated according to a plurality of received echo signals corresponding to the same frame, and the multi-dimensional measurement parameters are obtained based on the plurality of range-velocity spectra;

[0026] If the radar is a Doppler radar, a velocity spectrum is generated according to a plurality of received echo signals corresponding to the same frame, and the multi-dimensional measurement parameters are obtained based on the plurality of velocity spectra.

[0027] In an embodiment, the radar divides time windows for target detection, including:

[0028] jointly processing all echo signals received by the radar in a current time window for target detection, the steps of the joint processing including the following:

[0029] performing two-dimensional Fourier transform on all echo signals to obtain a range-velocity spectrum; or,

[0030] performing arithmetic averaging on data with the same sample point number in all echo signals, and calculating a range spectrum according to the arithmetic averaged data; or,

[0031] performing weighted combination on data with the same sample point number in all echo signals to obtain a combined signal, and generating a range spectrum according to the combined signal; or,

[0032] performing front-back difference processing on all echo signals according to the order of reception to obtain a plurality of difference signals, and calculating a range spectrum for each of the plurality of difference signals to obtain a plurality of range spectra.

[0033] In an embodiment, after detecting a target in the second and fourth working modes, the method further includes:

[0034] obtaining angle information of the detected target, the angle information including a horizontal angle, an azimuth angle and a pitch angle;

[0035] judging whether the angle information is within a preset range;

[0036] If yes, it is confirmed that the detected target is an expected target in the current working mode, and if no, it is not an expected target in the current working mode, wherein in the second working mode, the expected target refers to the second type of target, and in the fourth working mode, the expected target includes the first type of target, the second type of target and the third type of target.

[0037] The embodiment of the present application also provides a target detection device of a radar, comprising:

[0038] A first detection unit is configured to start a first working mode of the radar, and when a first type of target is detected, a second working mode of the radar is started;

[0039] A second detection unit is configured to detect a second type of target within a first preset time length, and when the second type of target is detected, a third working mode of the radar is started;

[0040] A third detection unit is configured to perform multi-dimensional measurement parameter extraction within a second preset time length, detect a third type of target, and when the third type of target is detected within the second preset time length, start a fourth working mode of the radar or control the radar to remain in the third working mode, wherein the multi-dimensional measurement parameter includes distance, speed, angle, breathing and heartbeat frequency, micro-Doppler and motion trajectory;

[0041] A fourth detection unit is configured to divide time windows to detect targets in the fourth working mode, and if an expected target is detected within a time window, enter a next time window to continue detecting whether the expected target exists, wherein the expected target includes the first type of target, the second type of target and the third type of target, the first type of target contains the second type of target, and the second type of target contains the third type of target.

[0042] The embodiment of the present application also provides a terminal, comprising a memory and a processor, wherein the memory stores an application processing program, and the application processing program is executed by the processor to implement the steps of the target detection method of the radar provided by any one of the embodiments of the present application.

[0043] The embodiment of the present application also provides a computer readable storage medium, which stores a plurality of instructions, and the instructions are suitable for being loaded by a processor to execute any target detection method of the radar provided by the embodiments of the present application.

[0044] The radar target detection method provided by the embodiment of the present application can start the first working mode of the radar, start the second working mode of the radar when the first type of target is detected, start the third working mode of the radar when the second type of target is detected within the first preset time length, perform multi-dimensional measurement parameter extraction by the radar within the second preset time length, and detect the third type of target. When the third type of target is detected within the second preset time length, the fourth working mode of the radar is started or the radar is still controlled to be in the third working mode. In the fourth working mode, the radar divides a time window to detect the target. If the expected target is detected within one time window, the next time window is entered to continue detecting whether the expected target exists. The expected target includes the first type of target, the second type of target and the third type of target. The set of the first type of target contains the second type of target, and the set of the second type of target contains the third type of target. The scheme provided by the embodiment of the present application can selectively start the next working mode of the radar according to the target detection result of the previous working mode of the radar, and gradually start the multi-dimensional parameter measurement function of the radar, which is helpful to reduce the influence of various micro-motion interferences in the interference environment and reduce the use power consumption of the radar. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0046] FIG. 1 is a first flowchart of the radar target detection method provided by the embodiment of the present application;

[0047] FIG. 2 is a structural schematic diagram of the radar target detection device provided by the embodiment of the present application;

[0048] FIG. 3 is a structural schematic diagram of the terminal provided by the embodiment of the present application. DETAILED DESCRIPTION

[0049] The exemplary embodiments will be described in detail herein with reference to the drawings. Unless otherwise indicated, the same numbers on the different drawings represent the same or similar elements. The following exemplary embodiments described in the following description are not meant to be limiting of the present application. Instead, they are meant to provide examples of apparatus and methods in accordance with aspects of the present application as detailed in the appended claims.

[0050] It should be noted that, in the present document, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element preceded by "comprises... a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. Also, the use of "a" or "an" to describe an element does not foreclose the existence of more than one of the elements in the process, method, article, or apparatus. The same reference sign used in different embodiments can designate similar but not necessarily identical components.

[0051] It should be understood that, although the steps in the flowcharts of the embodiments of the present application are shown in a certain order according to the arrows, the steps are not necessarily executed in the order of the arrows. Unless otherwise specified herein, the steps are not necessarily limited in the order of execution, and can be executed in other orders. Moreover, at least some of the steps in the figures can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution order is not necessarily sequential, but can be round-robin or alternately executed with at least some of the steps or sub-steps or stages of other steps.

[0052] It should be noted that, in the present document, step codes such as 101, 102, etc. are used to more clearly and concisely express the corresponding content, and do not constitute substantial restrictions on the order. Those skilled in the art may, for example, first execute 102 and then execute 101, etc. in the specific implementation, but these should be within the scope of protection of the present application.

[0053] Reference to "an embodiment" in this document means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative embodiments to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0054] The "existence of the first type of target" mentioned herein has the same meaning as "detection of the first type of target", "the first type of target does not disappear"; the "non-existence of the first type of target" mentioned herein has the same meaning as "non-detection of the first type of target", "disappearance of the first type of target"; the "existence of the second type of target" mentioned herein has the same meaning as "detection of the second type of target", "the second type of target does not disappear"; the "non-existence of the second type of target" mentioned herein has the same meaning as "non-detection of the second type of target", "disappearance of the second type of target"; the "existence of the third type of target" mentioned herein has the same meaning as "detection of the third type of target", "the third type of target does not disappear"; the "non-existence of the third type of target" mentioned herein has the same meaning as "non-detection of the third type of target", "disappearance of the third type of target".

[0055] The radar target detection method provided by the embodiment of the present application can be implemented by the radar target detection device provided by the embodiment of the present application, or an intelligent terminal and a server integrated with the radar target detection device.

[0056] Specifically, please refer to FIG. 1, which is a first flowchart of the radar target detection method provided by the embodiment of the present application. The specific flow of the radar target detection method can be as follows:

[0057] 101, start the first working mode of the radar, and start the second working mode of the radar when the first type of target is detected.

[0058] Specifically, after the radar is started, the first working mode is entered. At this time, the radar can periodically emit a first frame format detection signal. The radar detects the first type of target frame by frame. When the first type of target is detected, the radar enters the second working mode, otherwise the radar remains in the first working mode.

[0059] In an embodiment, when the radar is a FMCW (Frequency Modulated Continuous Wave) radar or a SFCW (Stepped Frequency Continuous Waveform) radar, the first frame format probe signal of each frame can be designed to contain a ranging signal waveform, wherein for the FMCW radar, the ranging signal waveform refers to a chirp signal, and for the SFCW radar, the ranging signal waveform refers to a SFCW waveform containing multiple frequency stepping points. In the following description of the present application, the ranging signal waveform has the above meaning; the radar receives, samples and performs static component suppression in the slow time dimension on the received signal of each frame, and then calculates to generate a range spectrum, detects targets in the generated range spectrum, and filters the detected targets according to a preset distance threshold. If there is a target within the preset distance threshold, it is considered that there is a first type of target, otherwise it is considered that there is no first type of target. Wherein, the suppression of static components in the slow time dimension and the generation of the range spectrum and the detection of targets in the range spectrum are common existing technologies, and the present application does not limit the operation details. In this embodiment, the first type of target refers to a non-stationary target after the distance threshold filtering after the static component suppression.

[0060] In an embodiment, when the radar is a Doppler radar or a SFCW radar, the first frame format probe signal of each frame can be designed as a Doppler radar signal waveform, wherein for the SFCW radar, the Doppler radar signal waveform refers to a SFCW waveform containing only one frequency point, and the SFCW radar at this time is equivalent to a Doppler radar. In the following description of the present application, the Doppler radar signal waveform of the SFCW radar has the above-mentioned meaning. The radar receives and samples the received signal of each frame and sends it to a high-pass filter, calculates the energy of the high-pass filter output signal, and if the obtained energy exceeds a preset energy threshold, it is judged that there is a first type of target, otherwise there is no first type of target; here, the first type of target refers to a non-stationary target after the energy threshold filtering after the static component suppression by the high-pass filter. It can be understood that in this embodiment, the energy intensity of the radar echo is related to the distance, and the distance is indirectly filtered by the preset energy threshold.

[0061] In an embodiment, when the radar is a Doppler radar or an SFCW radar, the first frame format probe signal of each frame can be designed as a plurality of Doppler radar signal waveforms arranged at equal time intervals. After the radar receives, samples and performs static component suppression in the slow time dimension on the received signal of each frame, the radar generates a velocity spectrum, detects targets in the generated velocity spectrum, filters the detected targets according to a preset velocity threshold, and if there are still targets within the preset velocity threshold range, it is considered that the first type of target exists, otherwise it is considered that the first type of target does not exist. Wherein, the static component suppression in the slow time dimension and the generation of the velocity spectrum, and the detection of targets in the velocity spectrum are existing common technologies, and the present application does not limit the operation details here. Here, the first type of target refers to a non-stationary target after the velocity threshold filtering after the static component suppression.

[0062] It can be understood that in the embodiments of the present application, the ranging radar refers to an FMCW radar or an SFCW radar that transmits a plurality of frequency stepping points. In the above embodiments, the radar is in the first working mode, and the radar simply and efficiently detects whether the first type of target exists from the distance dimension or the Doppler (velocity) dimension. It is still not possible to effectively distinguish whether the first type of target is micro-motion interference in the environment, such as the shaking of flowers, trees and plants in the environment, the vibration of objects in the daily home environment, etc. When the first type of target is found in the first working mode, the radar enters the second working mode to detect and confirm whether the second type of target exists. In the first working mode, in order to save the working power consumption of the radar, the frame rate of the radar transmitting the first frame format probe signal can be 0.5 Hz, 1 Hz, 2 Hz, 3 Hz, 4 Hz and 5 Hz, which needs to be selected according to the detection environment and the response time delay demand of the radar application, and the present application does not limit the frame rate.

[0063] 102. Detecting the second type of target within the first preset time length, and when the second type of target is detected, starting the third working mode of the radar.

[0064] Specifically, the radar enters the second working mode to further confirm the target and remove the interference, and confirm whether the second type of target exists. Specifically, when the second type of target is detected within T0 time, the radar enters the third working mode; when the second type of target is not detected within T0 time, the radar returns to the first working mode, wherein T0 is the first preset time length, representing the maximum time that the radar is in the second working mode, which can be set to 0.5 s, 1 s and 2 s, and needs to be selected according to the detection environment and the response time delay demand of the radar application, and the present application does not limit T0.

[0065] Wherein, when the radar is in the second working mode, the radar transmits the second frame format probe signal N times in total, wherein the time interval between the nth time of transmitting the probe signal and the (n-1)th time of transmitting the probe signal is t nn = 2, 3,..., N, N takes value 2, 3, 4, 5, all t n Not completely equal. t n n = 2, 3,..., N satisfy t2+t3+...+t N <T0, t n The arrangement of n = 2, 3,..., N can be designed in advance according to a non-uniform sampling or sparse sequence design method combined with the Doppler characteristics of the micro-motion interference in the environment.

[0066] In an embodiment, the radar is an FMCW radar or an SFCW radar, and the second frame format detection signal of each frame is designed as a ranging signal waveform. It can be understood that in the second working mode, N frames of second frame format detection signals are cumulatively transmitted. After receiving and sampling the received signal of the nth frame, the radar obtains the echo sampling signal r(n) = [r(n, 1), r(n, 2),..., r(n, h),..., r(n, H)] of the nth frame, where n = 1, 2, 3,..., N, h = 1, 2, 3,..., H, H represents the number of sampling points of each frame of signal, and r(n, h) represents the hth sampling point of the nth frame of echo sampling signal. The radar performs weighted combination on the data with the same sampling point number in all received signals in the slow time dimension to obtain a combined signal. Specifically, the combined signal is represented as rw = [rw(1), rw(2),..., rw(h),..., r(H)], rw(h) represents the hth element of the combined signal, rw(h) = x(h) * w, x(h) = [r(1, h), r(2, h),..., r(n, h),..., r(N, h)] is a row vector, w is a preset N * 1 weighting column vector, and w has a high-pass characteristic. The radar generates a range spectrum using the combined signal, detects targets in the obtained range spectrum, filters the detected targets according to a preset distance threshold, and if there is a target within the preset distance threshold, it is considered that the second type of target exists, otherwise, it is considered that the second type of target does not exist. Wherein, the range spectrum generation and target detection on the range spectrum are common technologies, and the present application does not limit the detection details. Here, the second type of target refers to the target detected after the low-speed interference is suppressed by the weighting combination and filtered by the preset distance threshold.

[0067] In an embodiment, the radar is a Doppler radar or an SFCW radar, the second frame format probe signal of each frame is designed as a Doppler radar signal waveform, and it can be understood that, in the second working mode, N frames of second frame format probe signals are cumulatively transmitted. After the radar receives and samples the received signal of the nth frame, an echo sample signal r(n) of the nth frame is obtained, where n = 1, 2, 3,..., N. The radar performs weighted combination on the data with the same sample point number in all received signals in the slow time dimension to obtain a combined signal, and specifically, the combined signal is represented as rw = x * w, x = [r(1), r(2),..., r(n),..., r(N)] is a row vector, w is a preset N * 1 weight column vector, w has a high-pass characteristic, the energy of the combined signal is calculated, if the energy exceeds a preset energy threshold E, a second type of target is detected, otherwise, no second type of target is detected, where the second type of target refers to a target filtered by the preset energy threshold after the low-speed interference is suppressed by the weighted combination, and it can be understood that, in this embodiment, the correlation between the echo energy intensity and the distance of the radar is used to indirectly perform distance filtering through the preset energy threshold.

[0068] In an embodiment, the radar is an FMCW radar or an SFCW radar, the second frame format probe signal of each frame is designed as a ranging signal waveform, and it can be understood that, in the second working mode, N frames of second frame format probe signals are cumulatively transmitted. After receiving and sampling the received signals of the nth frame, the radar obtains the echo sample signal r(n) of the nth frame, where n = 1, 2, 3,..., N, h = 1, 2, 3,..., H, H represents the number of sampling points of the signal of each frame, and r(n, h) represents the hth sampling point of the echo sample signal of the nth frame. The radar performs front-back difference processing on the received N received signals in the slow time dimension according to the receiving order, to obtain N-1 difference signals. Specifically, the lth difference signal is represented as rd(l) = [r(l+1, 1)-r(l, 1), r(l+1, 2)-r(l, 2),..., r(l+1, h)-r(l, h),..., r(l+1, H)-r(l, H)], where l = 1, 2, 3,..., N-1, r(l, h) represents the hth sampling point of the echo sample signal of the lth frame, the radar generates N-1 range spectra by using the N-1 difference signals, detects targets in the obtained range spectra, and filters the detected targets in each range spectrum according to a preset distance threshold. If K range spectra of the N-1 range spectra detect targets within the preset distance threshold, and K is greater than a preset threshold value K0, it is considered that a second type of target is detected, otherwise it is judged that there is no second type of target, K0 is 1, 2, 3, 4, and does not exceed N-1, where the generation of the range spectrum and the detection of the target in the range spectrum are common technologies, and the detection method and details are not limited in the present application. Here, the second type of target refers to a target that is filtered after being suppressed by difference and low-speed interference.

[0069] In an embodiment, the radar is a Doppler radar or an SFCW radar, and the second frame format probe signal of each frame is designed as a Doppler radar signal waveform. It can be understood that, in the second working mode, N frames of second frame format probe signals are cumulatively transmitted. After receiving and sampling the received signals of the nth frame, the radar obtains the echo sampling signal r(n) of the nth frame, where n = 1, 2, 3,..., N. The radar performs forward-backward difference processing on the received N received signals in the slow time dimension according to the order of reception, to obtain N-1 difference signals. Specifically, the lth difference signal is represented as rd(l) = r(l+1) - r(l), where l = 1, 2, 3,..., N-1. The energy values of the N-1 difference signals are calculated. If K energy values in the N-1 energy values are greater than a preset energy value threshold, and K is greater than a preset threshold value K0, it is judged that a second type of target is detected, otherwise it is judged that there is no second type of target. K0 takes a value of 1, 2, 3, or 4, and the value of K0 does not exceed N-1. Here, the second type of target refers to a target filtered by the preset energy threshold after difference suppression of low-speed interference. It can be understood that, in this embodiment, the distance filtering is indirectly performed by using the correlation between the radar echo energy intensity and the distance.

[0070] In the second working mode, if the radar supports angle measurement, angle measurement can also be started to obtain angle information, so as to further confirm whether the target detected in each of the above-mentioned embodiments of the second working mode after distance or speed filtering is within a preset angle range. The angle information includes a horizontal angle, an azimuth angle, and a pitch angle. If the target detected in the second working mode after distance or speed filtering is within the preset angle range (a preset horizontal angle, a preset azimuth angle, and a preset pitch angle range), it is confirmed that the detected target is the expected target in the second working mode, i.e., a second type of target, otherwise, the detected target is not a second type of target. If all the targets detected in the second working mode after distance or speed filtering are not within the preset angle range, it is judged that there is no second type of target, otherwise, it is judged that there is a second type of target.

[0071] It can be understood that, in the second working mode, the N frames of probe signals are designed in a non-equidistant interval form. Compared with an equidistant interval form, a high filtering can be realized in the slow time dimension with a smaller N value, which helps to reduce the power consumption of the radar in the second working mode while suppressing the micro-motion interference in the environment. That is, on the premise that the first type of target has been detected in the first working mode, the influence of the micro-motion interference in the environment is further eliminated. If the target can still be detected, it is considered that there is a second type of target, and the radar can enter a third working mode.

[0072] 103、In the second preset time length, the radar performs multi-dimensional measurement parameter extraction, detects the third type of target, and when the third type of target is detected in the second preset time length, the fourth working mode of the radar is started or the radar is still controlled to be in the third working mode.

[0073] The multi-dimensional measurement parameters include distance, speed, angle, respiratory and heartbeat frequency, micro-Doppler, and motion trajectory. Specifically, when the radar enters the third working mode, the radar performs accurate extraction and tracking of the multi-dimensional measurement parameters, including distance, speed, angle, respiratory and heartbeat frequency, micro-Doppler, and motion trajectory. When the third type of target is not detected in the second preset time length T1, the radar returns to the first working mode. When the third type of target is detected in the second preset time length T1, the radar can enter the fourth working mode to judge the disappearance of the expected target in the fourth working mode. When the third type of target is detected in the second preset time length T1, the radar can continue to be in the third working mode and judge the disappearance of the third type of target. If the third type of target is not detected in a continuous T1 time, it is considered that the third type of target disappears, and the radar returns to the first working mode.

[0074] When in the third working mode, the radar transmits a frame of third frame format probe signals and receives corresponding echo signals every Δt0 time. For a ranging radar, each frame of third frame format probe signals contains Q ranging signal waveforms arranged at equal time intervals. The radar generates a range-velocity spectrum using Q received echo signals corresponding to the same frame, and further extracts the measurement parameters of the target using multiple range-velocity spectra, where Δt0 is greater than or equal to the product of Q and Δt1, Δt0, Δt1, and Q are preset values, and Δt1 represents the time interval of Q signal waveforms arranged at equal time intervals in the same frame. For a Doppler radar, each frame of third frame format probe signals contains Q Doppler radar signal waveforms arranged at equal time intervals. The radar generates a velocity spectrum using Q received echo signals corresponding to the same frame, and further extracts the measurement parameters of the target using multiple velocity spectra, where Δt0 is greater than or equal to the product of Q and Δt1, Δt0, Δt1, and Q are preset values, and Δt1 represents the time interval of Q signal waveforms arranged at equal time intervals in the same frame.

[0075] In an embodiment, the radar is a FMCW radar or a SFCW radar, and the third type of target is human movement. The radar transmits a frame of third frame format probe signals and receives corresponding echo signals every Δt0 time. Each frame of the third frame format probe signals includes Q ranging signal waveforms arranged at equal time intervals. The radar generates a range-velocity spectrum by using Q received echo signals corresponding to the same frame after static component suppression. The radar further extracts measurement parameters of the target, including range, velocity, angle, micro-Doppler, and motion trajectory, by using the obtained multiple range-velocity spectra. The radar determines whether the third type of target exists by using methods such as kinematic model point cloud data association, Kalman filter tracking, clustering analysis, or deep learning based on the obtained multiple range-velocity spectra. In this mode, if the radar is a MIMO radar, all the transmitting and receiving antennas of the radar form an antenna array and participate in parameter measurement and extraction. The specific detection method of human movement based on the ranging radar (FMCW radar or SFCW radar) is a publicly available technology, and the present application does not limit the specific detection method of the third type of target (human movement).

[0076] When the third type of target is not detected within T1 time, the radar returns to the first working mode. When the third type of target is detected within T1 time, the radar can optionally enter the fourth working mode. When the third type of target is detected within T1 time, the radar can optionally continue to be in the third working mode and determine whether the third type of target disappears. If the third type of target is not detected within a continuous T1 time, it is considered that the third type of target disappears, and the radar returns to the first working mode. T1 is set as an integer multiple of Δt0.

[0077] In an embodiment, the radar is a FMCW radar or a SFCW radar, and the third type of target is human vital signs. The radar transmits a frame of third frame format probe signals and receives corresponding echo signals every Δt0 time. Each frame of the third frame format probe signals includes Q ranging signal waveforms. The radar generates a range-velocity spectrum by using Q received echo signals corresponding to the same frame after static component suppression. The radar further extracts measurement parameters of the target, including range, velocity, angle, micro-Doppler, and motion trajectory, by using the obtained multiple range-velocity spectra. The radar determines whether the third type of target exists by using methods such as kinematic model point cloud data association, clustering analysis, or deep learning based on the obtained multiple range-velocity spectra. In this mode, if the radar is a MIMO radar, all the transmitting and receiving antennas of the radar form an antenna array and participate in parameter measurement and extraction. The specific detection method of human vital signs based on the ranging radar (FMCW radar or SFCW radar) is a publicly available technology, and the present application does not limit the specific detection method of the third type of target (human vital signs).

[0078] When the third type of target is not detected within T1 time, the radar returns to the first working mode; when the third type of target is detected within T1 time, optionally, the radar can enter the fourth working mode; when the third type of target is detected within T1 time, optionally, the radar can continue to be in the third working mode, and the disappearance of the third type of target is judged, that is, if the third type of target is not detected within a continuous T1 time, it is considered that the third type of target disappears, the radar returns to the first working mode, and T1 is set as an integer multiple of Δt0.

[0079] In an embodiment, the radar is a Doppler radar, and the third type of target is a human vital sign. The radar transmits a frame of third frame format detection signal every Δt0 time and receives the corresponding echo signal, wherein each frame of third frame format detection signal contains Q Doppler radar signal waveforms arranged at equal time intervals, and the corresponding echo signal is received. The radar generates a velocity spectrum using Q received echo signals corresponding to the same frame, and further extracts the measurement parameters of the target including velocity, angle, micro-Doppler, etc. using the obtained multiple velocity spectra. The breathing and heartbeat features of the human body can be extracted based on the kinematic model point cloud data association, clustering analysis or deep learning method of the human vital sign based on the obtained multiple velocity spectra, and whether the third type of target exists is judged. In this mode, if the radar is a MIMO radar, all the transmitting and receiving antennas of the radar form an antenna array and participate in parameter measurement and extraction. The specific detection method of the human vital sign based on the Doppler radar is the existing public technology, and the present application does not limit the specific detection method of the third type of target (human vital sign). When the third type of target is not detected within T1 time, the radar returns to the first working mode; when the third type of target is detected within T1 time, optionally, the radar can enter the fourth working mode; when the third type of target is detected within T1 time, optionally, the radar can continue to be in the third working mode, and the disappearance of the third type of target is judged, that is, if the third type of target is not detected within a continuous T1 time, it is considered that the third type of target disappears, the radar returns to the first working mode, and T1 is set as an integer multiple of Δt0.

[0080] In the third working mode, the radar performs target parameter measurement and target detection with high computing load. After the first working mode and the second working mode confirm the existence of the third type of target, the third working mode is entered, which helps to avoid frequent running of the parameter measurement and detection algorithm with high computing load in the interference environment, thereby reducing the power consumption of the radar. When the radar detects the third type of target in the third working mode, the radar needs to send an indication signal to the host unit that the (third type of) target is detected, and the host unit performs subsequent linkage operation, such as sending an instruction to the controlled device through wired connection or wireless connection to require the controlled device to perform a response action. It is a common public application way that the radar detects the target, informs the host unit after discovering the target, and the host unit controls the controlled device to perform linkage operation. The present application does not limit the content related thereto.

[0081] 104、In the fourth working mode, the radar divides time windows to detect targets, and if the expected target is detected in a time window, the next time window is entered to continue detecting whether the expected target exists, and the expected target includes the first type of target, the second type of target and the third type of target.

[0082] Specifically, when the radar enters the fourth working mode, the radar transmits a fourth frame format detection signal to perform target disappearance judgment, that is, if no target is found in the current time window, the radar returns to the first working mode, and if a target is found in the current time window, the radar enters the next time window to continue detecting whether the target disappears, wherein each time window has the same length, and in the fourth working mode, the expected target includes the first type of target, the second type of target and the third type of target, the set of the first type of target contains the second type of target, and the set of the second type of target contains the third type of target. According to the application scene and system power consumption design of the radar, it can be selected in advance which one of the three types of targets is the expected target in the fourth working mode. The radar uses all the received signals in each time window for joint processing to confirm whether the target in the current time window disappears.

[0083] In the fourth working mode, all the received signals in each time window are used for joint processing to obtain better SNR (signal-to-noise ratio) gain, and the joint processing operation includes:

[0084] Joint processing operation one, performing 2-dimensional discrete Fourier transform on all the echo signals received in a time window to obtain a range-velocity spectrum;

[0085] Joint processing operation two, calculating the arithmetic mean of the data with the same sampling point number in all the echo signals received in a time window, and calculating a range spectrum by using the data after the arithmetic mean;

[0086] The joint processing operation three is to combine data with the same sampling point number in all echo signals received in a time window by weighting to obtain a combined signal, and generate a range profile by using the combined signal.

[0087] The joint processing operation four is to perform front-back difference processing on all echo signals received in a time window in a slow time dimension according to the order of reception to obtain a plurality of difference signals, and obtain a plurality of range profiles by calculating range profiles of the plurality of difference signals.

[0088] The above-mentioned joint processing operations have different calculation complexities and detection capabilities for targets, and can be selected systematically according to application scenarios and power consumption levels of the radar, and the present application does not limit this.

[0089] In an embodiment, the radar is an FMCW radar or an SFCW radar, the detection target (expected target) of the radar is the first type of target, the radar transmits a fourth frame format detection signal every Δt2 time and receives the corresponding echo every Δt2 time, the fourth frame format detection signal of each frame is designed as a ranging signal waveform; the received signals of the 1st frame to the Wth frame are signals in a first time window, the received signals of the 1+Wth frame to the 2Wth frame are signals in a second time window, and so on; the W frames of received signals in each time window form a data matrix, the obtained data matrix can be subjected to static component suppression, and a range-velocity spectrum can be calculated and generated, targets are detected in the obtained range-velocity spectrum, the detected targets are filtered according to a preset range threshold and a preset velocity threshold, if there are still targets after filtering, it is considered that the first type of target exists, otherwise it is considered that no target is found (the target disappears); or the data with the same sampling point number in each data matrix can be averaged respectively, a range profile can be calculated and generated by using the averaged data, targets are detected in the obtained range profile, the detected targets are filtered according to a preset range threshold, if there are still targets after filtering, it is considered that the first type of target exists, otherwise it is considered that no target is found (the target disappears). Wherein, the generation of the range-velocity spectrum or the range profile and the detection of the target in the range-velocity spectrum or the range profile are common technologies, and the present application does not limit the calculation and detection details.

[0090] In an embodiment, the radar is a Doppler radar or an SFCW radar, the detection target (expected target) of the radar is the first type of target, the radar transmits a fourth frame format probe signal every Δt2 time and receives the corresponding echo signal, the fourth frame format probe signal of each frame is designed as a Doppler radar waveform; the received signals of the 1st frame to the Wth frame are signals in a first time window, the received signals of the 1+ Wth frame to the 2Wth frame are signals in a second time window, and so on; the received signals of W frames in each time window form a data vector, after static component suppression of the obtained data vector, a velocity spectrum is generated, the target is detected in the obtained velocity spectrum, the detected target is filtered according to a preset velocity threshold, if there is still a target after filtering, it is considered that there is the first type of target, otherwise, it is considered that no target is found (the target disappears), wherein the generation of the velocity spectrum and the detection of the target in the velocity spectrum are common technologies, and the present application does not limit the calculation and detection details.

[0091] In the above two embodiments, the detection target of the fourth working mode is the first type of target, which means that the radar detects the moving target in the environment, including human movement and micro movement, and the algorithm detection load of the radar is lower compared with the third working mode, under the premise that the third type of target is detected in the third working mode, the radar enters the fourth working mode for low-computation-load target detection, only the disappearance of the target is judged, and the accurate measurement and tracking of the target are not performed, which is helpful to reduce the calculation power consumption of the radar.

[0092] In an embodiment, the radar is an FMCW radar or an SFCW radar, the detection target (expected target) of the radar is the second type of target, the radar transmits a fourth frame format probe signal every Δt2 time and receives the corresponding echo signal, each frame of the fourth frame format probe signal contains N ranging signal waveforms arranged at unequal time intervals, the arrangement mode of the N ranging signal waveforms in the time dimension is the same as that in the second working mode, and the time span of each time window is Δt2, in each time window, the radar receives the echo signal of one frame of the fourth frame format probe signal (the echo signals of the N ranging signal waveforms arranged at unequal time intervals), and the radar processes the received signal in the same manner as in the embodiment of the second working mode to detect whether the second type of target exists.

[0093] In an embodiment, the radar is a Doppler radar or an SFCW radar, the detection target (expected target) of the radar is the second type of target, the radar transmits a fourth frame format probe signal every Δt2 time and receives the corresponding echo signal, each frame of the fourth frame format probe signal contains N Doppler radar signal waveforms arranged in unequal time intervals, the arrangement of the N Doppler radar signal waveforms in the time dimension is the same as that in the second working mode, and the time span of each time window is Δt2. In each time window, the radar receives the echo signal of a frame of the fourth frame format probe signal (the echo signal of the N ranging signal waveforms arranged in unequal time intervals). The radar processes the received signal in the same manner as in the embodiment of the second working mode to detect whether the second type of target exists.

[0094] In the above two embodiments, the detection target of the fourth working mode is the second type of target, which means that the radar detects non-low-speed interference targets in the environment. Compared with the third working mode, the algorithm of the radar has a lower detection load. Under the premise that the third type of target has been detected in the third working mode, the radar enters the fourth working mode for low-computation-load target detection, only makes a judgment on the disappearance of the target, and no longer performs accurate measurement and tracking of the target parameters, which helps to reduce the computing power consumption of the radar.

[0095] In an embodiment, the radar is an FMCW radar or an SFCW radar, the detection target (expected target) of the radar is the third type of target (human movement), the radar transmits a fourth frame format probe signal every Δt2 time and receives the corresponding echo signal, each frame of the fourth frame format probe signal contains Q ranging signal waveforms arranged in equal time intervals, and the time span of each time window is Δt2. In each time window, the radar receives the echo signal of a frame of the fourth frame format probe signal (the echo signal of the Q ranging signal waveforms arranged in equal time intervals). The radar processes the received signal in the same manner as in the embodiment of the third working mode to detect whether the third type of target disappears.

[0096] In an embodiment, the radar is an FMCW radar or an SFCW radar, the detection target (expected target) of the radar is the third type of target (human vital signs), the radar transmits a fourth frame format probe signal every Δt2 time and receives the corresponding echo signal, each frame of the fourth frame format probe signal contains Q ranging signal waveforms arranged in equal time intervals, and the time span of each time window is Δt2. In each time window, the radar receives the echo signal of a frame of the fourth frame format probe signal (the echo signal of the Q ranging signal waveforms arranged in equal time intervals). The radar processes the received signal in the same manner as in the embodiment of the third working mode to detect whether the third type of target disappears.

[0097] In an embodiment, the radar is a Doppler radar or an SFCW radar, the detection target (expected target) of the radar is the third type of target (human vital signs), the radar transmits a fourth frame format probe signal every Δt2 time and receives the corresponding echo signal, wherein the fourth frame format probe signal of each frame includes Q Doppler radar signal waveforms arranged at equal time intervals, and the time span of each time window is Δt2. In each time window, the radar receives the echo signal of a frame of fourth frame format probe signal (the echo signal of Q Doppler radar signal waveforms arranged at equal time intervals). The radar processes the received signal in the same way as in the third working mode embodiment to detect whether the third type of target disappears.

[0098] In the above three embodiments, the parameter Δt2 can be set to be greater than Δt0, which means that after the third type of target has been detected in the third working mode, the radar enters a lower detection frame rate in the fourth working mode to detect whether the third type of target disappears. At this time, compared with the third working mode, the fourth working mode can determine whether the third type of target disappears with lower power consumption.

[0099] In the fourth working mode embodiments, optionally, if the radar supports angle measurement, angle measurement can be started to obtain angle information of the target detected in the embodiment to further confirm whether the detected target is the expected target in the fourth working mode, wherein the angle information includes horizontal angle, azimuth angle and pitch angle. In an embodiment of the above fourth working mode, if a certain detected target is within a preset angle range (a preset horizontal angle, a preset azimuth angle and a preset pitch angle range), it is confirmed that the detected target is the expected target in the fourth working mode, otherwise, the detected target is not the expected target in the fourth working mode. In an embodiment of the above fourth working mode, if all the detected targets are not within the preset angle range in a time window, it is determined that no target is found in the time window, i.e. the target disappears, otherwise, it is determined that the target does not disappear in the time window.

[0100] When the radar detects that the target disappears in the fourth working mode, the radar needs to send an indication signal of target disappearance to the main control unit, and the main control unit performs subsequent linkage operation, such as sending an instruction to the controlled device through wired connection or wireless connection to require the controlled device to perform a response action. The present application does not limit the content related thereto.

[0101] In addition, the radar can also coexist with a passive infrared detector (PIR) to perform the target detection method of the radar. In an embodiment, when the passive infrared detector is working, the radar remains in a shutdown or hibernation state. When the passive infrared detector detects a target, the radar is turned on or exits the hibernation and enters the first working mode, and the time for which the radar is in the first working mode is timed. The radar continues to work according to the hierarchical working mechanism of the first working mode to the fourth working mode of the present application. When the time for which the radar is in the first working mode expires, the radar returns to the shutdown or hibernation state; when the radar needs to exit the second working mode in the second working mode, the radar returns to the shutdown or hibernation state; when the radar needs to exit the third working mode in the third working mode without finding a target, the radar returns to the shutdown or hibernation state; and when the radar needs to exit the fourth working mode in the fourth working mode, the radar returns to the shutdown or hibernation state.

[0102] In an embodiment, when the passive infrared detector is working, the radar remains in a shutdown or hibernation state. When the passive infrared detector detects a target, the radar is turned on or exits the hibernation and enters the second working mode. The radar continues to work according to the hierarchical working mechanism of the second working mode to the fourth working mode of the present application. When the radar needs to exit the second working mode in the second working mode, the radar returns to the shutdown or hibernation state; when the radar needs to exit the third working mode in the third working mode without finding a target, the radar returns to the shutdown or hibernation state; and when the radar needs to exit the fourth working mode in the fourth working mode, the radar returns to the shutdown or hibernation state.

[0103] In an embodiment, when the passive infrared detector is working, the radar remains in a shutdown or hibernation state. When the passive infrared detector detects a target, the radar is turned on or exits the hibernation and enters the third working mode. The radar continues to work according to the hierarchical working mechanism of the third working mode to the fourth working mode of the present application. When the radar needs to exit the third working mode in the third working mode without finding a target, the radar returns to the shutdown or hibernation state; and when the radar needs to exit the fourth working mode in the fourth working mode, the radar returns to the shutdown or hibernation state.

[0104] In an embodiment, when the passive infrared detector is working, the radar remains in a shutdown or hibernation state. When the passive infrared detector detects a target, the radar is turned on or exits the hibernation and enters the fourth working mode. When the radar needs to exit the fourth working mode in the fourth working mode, the radar returns to the shutdown or hibernation state.

[0105] The four embodiments described above need to be selected after systematic design according to the detection time delay of the application scene, the power consumption distribution of the multi-sensor, and the anti-interference design of the radar, and the present application does not limit this.

[0106] It should be noted that various embodiments of the same radar (FMCW radar, SFCW radar or Doppler radar) in the four working modes can be combined according to the use requirements of the application scene, for example, for SFCW radar, the embodiments of the first working mode (SFCW radar in Doppler working mode), the embodiments of the second working mode (SFCW radar in conventional ranging radar mode), the embodiments of the third working mode (SFCW radar in conventional ranging radar mode), and the embodiments of the fourth working mode (SFCW radar in Doppler radar mode) are combined for use.

[0107] It should be noted that in actual implementation, it is preferred to recommend that in the first working mode, the radar detects and judges whether the first type of target exists from the distance or speed dimension, in the second working mode, the radar jointly judges whether the second type of target exists from the distance-Doppler dimension (after Doppler velocity low-speed interference suppression, distance filtering is performed), in the third working mode, the radar detects and identifies whether the third type of target exists by using multi-dimensional features (such as speed, distance, angle, micro-Doppler, kinematic trajectory, etc.). In the first to third working modes, the complexity of radar signal processing gradually increases, the judgment condition of radar detection target gradually shrinks, the first type of target set contains the second type of target, and the second type of target set contains the third type of target. In the whole working process, when it is not determined whether the third type of target which needs to be finally detected exists, only part of the detection function is started to confirm whether the first type of target and the second type of target exist, and when it is found that the environmental interference is excluded, the accurate parameter measurement and tracking for the third type of target are started. With this strategy, the working power consumption of the radar is reduced, and the power of the radar is saved.

[0108] According to the radar target detection method provided in the embodiments of the present application, the first working mode of the radar can be started, when the first type of target is detected, the second working mode of the radar is started, and the second type of target is detected within the first preset time length. When the second type of target is detected, the third working mode of the radar is started, and the radar performs multi-dimensional measurement parameter extraction within the second preset time length, and the third type of target is detected. When the third type of target is detected within the second preset time length, the fourth working mode of the radar is started or the radar is controlled to remain in the third working mode. In the fourth working mode, the radar divides a time window to detect the target. If the expected target is detected within one time window, the next time window is entered to continue detecting whether the expected target exists. The expected target includes the first type of target, the second type of target and the third type of target. The first type of target set contains the second type of target, and the second type of target set contains the third type of target. The scheme provided in the embodiments of the present application can selectively start the next working mode of the radar according to the target detection result of the previous working mode of the radar, and gradually start the multi-dimensional parameter measurement function of the radar, which is helpful to reduce the influence of various micro-motion interferences in the interference environment and reduce the use power consumption of the radar.

[0109] In order to implement the above method, the embodiments of the present application further provide a radar target detection device. The radar target detection device can be integrated in a terminal device such as a mobile phone, a tablet computer or the like.

[0110] For example, as shown in FIG. 2, it is a first structure schematic diagram of the radar target detection device provided by the embodiments of the present application. The radar target detection device can include:

[0111] The first detection unit 301 is configured to start the first working mode of the radar, and when the first type of target is detected, the second working mode of the radar is started.

[0112] The second detection unit 302 is configured to detect the second type of target within the first preset time length, and when the second type of target is detected, the third working mode of the radar is started.

[0113] The third detection unit 303 is configured to perform multi-dimensional measurement parameter extraction by the radar within the second preset time length, detect the third type of target, and when the third type of target is detected within the second preset time length, the fourth working mode of the radar is started or the radar is controlled to remain in the third working mode. The multi-dimensional measurement parameters include distance, speed, angle, breathing and heartbeat frequency, micro-Doppler and motion trajectory.

[0114] The fourth detection unit 304 is configured to, in the fourth working mode, divide time windows for target detection, and if the expected target is detected in a time window, continue to detect whether the expected target exists in the next time window, the expected target including the first target, the second target and the third target, the first target set containing the second target, and the second target set containing the third target.

[0115] The radar target detection device provided by the embodiment of the present application can start the first working mode of the radar, start the second working mode of the radar when the first target is detected, start the third working mode of the radar when the second target is detected, perform multi-dimensional measurement parameter extraction in the second preset time length, and detect the third target, start the fourth working mode of the radar or control the radar to remain in the third working mode when the third target is detected in the second preset time length, divide time windows for target detection in the fourth working mode, and if the expected target is detected in a time window, continue to detect whether the expected target exists in the next time window, the expected target including the first target, the second target and the third target, the first target set containing the second target, and the second target set containing the third target. The scheme provided by the embodiment of the present application can selectively start the next working mode of the radar according to the target detection result of the previous working mode of the radar, and gradually start the multi-dimensional parameter measurement function of the radar, which is helpful to reduce the influence of various micro-motion interferences in an interference environment and reduce the use power consumption of the radar.

[0116] The embodiment of the present application further provides a terminal, as shown in FIG. 3, which can include a radio frequency (RF) circuit 601, a memory 602 including one or more computer readable storage media, an input unit 603, a display unit 604, a sensor 605, an audio circuit 606, a wireless fidelity (WiFi) module 607, a processor 608 including one or more processing cores, and a power supply 609, and the like. Those skilled in the art can understand that the terminal structure shown in FIG. 3 does not constitute a limitation on the terminal, and can include more or fewer components than the illustration, or combine certain components, or different component arrangements. Among them:

[0117] The RF circuit 601 can be used for receiving and sending signals in the process of information or communication, in particular, receiving the downlink information from the base station and sending the uplink data to the base station. Generally, the RF circuit 601 includes, but is not limited to, an antenna, at least one amplifier, a tuner, one or more oscillators, a Subscriber Identity Module (SIM) card, a transceiver, a coupler, a Low Noise Amplifier (LNA), a duplexer, etc. In addition, the RF circuit 601 can also communicate with the network and other devices through wireless communication. The wireless communication can use any communication standards or protocols, including but not limited to Global System for Mobile Communication (GSM), General Packet Radio Service (GPRS), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE), email, Short Messaging Service (SMS), etc.

[0118] The memory 602 can be used to store software programs and modules, and the processor 608 can execute various functions and information processing by running the software programs and modules stored in the memory 602. The memory 602 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application program required by a function (such as a sound playing function, an image playing function, etc.), etc.; the data storage area can store data created according to the use of the terminal (such as audio data, a phone book, etc.), etc. In addition, the memory 602 can include a high-speed random access memory, and can also include a non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, or other volatile solid-state memory device. Accordingly, the memory 602 can also include a memory controller to provide access for the processor 608 and the input unit 603 to the memory 602.

[0119] The input unit 603 can be configured to receive input of numbers or characters, and generate key signals, mouse signals, or lever signals corresponding to a user's setting or function control. Specifically, in one embodiment, the input unit 603 can include a touch-sensitive surface and other input devices. The touch-sensitive surface, also known as a touch display or a touch pad, can collect a user's touch operation (e.g., a user's operation using a finger, a stylus, or any suitable object or accessory near or on the touch-sensitive surface) and drive a corresponding connection device according to a pre-set program. Optionally, the touch-sensitive surface can include a touch detection device and a touch controller. The touch detection device detects a user's touch position and detects a signal caused by a touch operation, and transmits the signal to the touch controller. The touch controller receives the touch information from the touch detection device, converts it into touch coordinates, and transmits it to the processor 608, and can receive commands from the processor 608 and execute them. In addition, the touch-sensitive surface can be implemented in various types such as a resistive type, a capacitive type, an infrared type, and a surface acoustic wave type. In addition to the touch-sensitive surface, the input unit 603 can include other input devices. Specifically, the other input devices can include one or more of a physical keyboard, a function key (e.g., a volume control key, an on / off key, etc.), a trackball, a mouse, a lever, etc.

[0120] The display unit 604 can be configured to display information input by a user or information provided to the user, and various graphical user interfaces of the terminal, which can be composed of graphics, text, icons, video, and any combination thereof. The display unit 604 can include a display panel, which can be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), etc. Further, the touch-sensitive surface can cover the display panel, and when the touch-sensitive surface detects a touch operation on or near the touch-sensitive surface, it transmits the touch event to the processor 608 to determine the type of the touch event, and then the processor 608 provides a corresponding visual output on the display panel according to the type of the touch event. Although in FIG. 3, the touch-sensitive surface and the display panel are implemented as two independent components to achieve input and output functions, in some embodiments, the touch-sensitive surface and the display panel can be integrated to achieve input and output functions.

[0121] The terminal can also include at least one sensor 605, such as a light sensor, a motion sensor, and other sensors. Specifically, the light sensor can include an ambient light sensor that can adjust the brightness of the display panel according to the brightness of ambient light, and a proximity sensor that can turn off the display panel and / or backlight when the terminal is moved to the ear. As one of the motion sensors, the gravity acceleration sensor can detect the magnitude of acceleration in each direction (generally three axes), and when at rest, can detect the magnitude and direction of gravity, and can be used for applications such as identifying the posture of the mobile phone (such as switching between landscape and portrait screens, related games, magnetometer posture calibration), vibration recognition related functions (such as pedometers, tapping), and the like. As for other sensors that the terminal can also be configured, such as a gyroscope, a barometer, a hygrometer, a thermometer, an infrared sensor, and the like, they will not be described here.

[0122] The audio circuit 606, the speaker, and the microphone can provide an audio interface between the user and the terminal. The audio circuit 606 can convert the received audio data into an electrical signal and transmit it to the speaker, which converts the electrical signal into a sound signal and outputs it. On the other hand, the microphone collects a sound signal and converts it into an electrical signal, which is received by the audio circuit 606 and converted into audio data. The audio data is then output to the processor 608 for processing, and then transmitted to another terminal via the RF circuit 601, or output to the memory 602 for further processing. The audio circuit 606 can also include a jack for connecting external earphones to the terminal.

[0123] WiFi is a short-range wireless transmission technology. The terminal can help users send and receive emails, browse web pages, and access streaming media through the WiFi module 607, which provides users with wireless broadband Internet access. Although the WiFi module 607 is shown in FIG. 3, it is understood that it is not a necessary component of the terminal and can be omitted without changing the essence of the application.

[0124] The processor 608 is the control center of the terminal, which connects all parts of the terminal through various interfaces and lines, executes various functions of the terminal and processes data by running or executing software programs and / or modules stored in the memory 602, and calling data stored in the memory 602, thereby monitoring the terminal as a whole. Optionally, the processor 608 can include one or more processing cores; preferably, the processor 608 can integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface, and application programs, and the modem processor mainly processes wireless communication. It is understood that the above-mentioned modem processor can also not be integrated into the processor 608.

[0125] The terminal also includes a power supply 609 (such as a battery) for supplying power to each component. Preferably, the power supply can be logically connected to the processor 608 through a power management system, so that the power management system can realize functions such as management of charging, discharging, and power consumption management. The power supply 609 can also include one or more direct or alternating current power supplies, a recharging system, a power supply fault detection circuit, a power supply converter or inverter, a power supply status indicator, and any other components.

[0126] Although not shown, the terminal can also include a camera, a Bluetooth module, and the like, which will not be described here. In the present embodiment, the processor 608 in the terminal will load the executable file corresponding to the process of one or more application programs into the memory 602 according to the following instructions, and run the application program stored in the memory 602 by the processor 608, so as to realize various functions:

[0127] Turning on a first working mode of the radar, and turning on a second working mode of the radar when detecting a first type of target;

[0128] Detecting a second type of target within a first preset time period, and turning on a third working mode of the radar when detecting the second type of target;

[0129] Within a second preset time period, the radar performs multi-dimensional measurement parameter extraction to detect a third type of target, and turns on a fourth working mode of the radar or controls the radar to remain in the third working mode when detecting the third type of target within the second preset time period, the multi-dimensional measurement parameter including distance, speed, angle, breathing and heartbeat frequency, micro-Doppler, and motion trajectory;

[0130] In the fourth working mode, the radar divides time windows to detect targets, and if an expected target is detected within a time window, the next time window is entered to continue detecting whether the expected target exists, the expected target including the first type of target, the second type of target, and the third type of target, the set of the first type of target containing the second type of target, and the set of the second type of target containing the third type of target.

[0131] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the detailed description of the radar target detection method above, which will not be described here.

[0132] It can be learned from the above that the terminal of the embodiment of the present application can start the first working mode of the radar, when the first type of target is detected, the second working mode of the radar is started, the second type of target is detected within the first preset time length, when the second type of target is detected, the third working mode of the radar is started, the radar performs multi-dimensional measurement parameter extraction within the second preset time length, and the third type of target is detected, when the third type of target is detected within the second preset time length, the fourth working mode of the radar is started or the radar is controlled to remain in the third working mode, in the fourth working mode, the radar divides a time window to detect the target, if the expected target is detected within one time window, the next time window is entered to continue to detect whether the expected target exists, the expected target includes the first type of target, the second type of target and the third type of target, the set of the first type of target contains the second type of target, and the set of the second type of target contains the third type of target. The scheme provided by the embodiment of the present application can selectively start the next working mode of the radar according to the target detection result of the previous working mode of the radar, and gradually start the multi-dimensional parameter measurement function of the radar, which is helpful to reduce the influence of various micro-motion interferences in the interference environment and reduce the use power consumption of the radar.

[0133] Those skilled in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructions or controlled by instructions related to hardware, which can be stored in a computer readable storage medium and loaded and executed by a processor.

[0134] To this end, the embodiment of the present application provides a computer readable storage medium, which stores a plurality of instructions capable of being loaded by a processor to execute the steps in any target detection method of the radar provided by the embodiment of the present application. For example, the instructions can execute the following steps:

[0135] starting the first working mode of the radar, and when the first type of target is detected, starting the second working mode of the radar;

[0136] detecting the second type of target within the first preset time length, and when the second type of target is detected, starting the third working mode of the radar;

[0137] within the second preset time length, the radar performs multi-dimensional measurement parameter extraction, and detects the third type of target, when the third type of target is detected within the second preset time length, the fourth working mode of the radar is started or the radar is controlled to remain in the third working mode, and the multi-dimensional measurement parameters include distance, speed, angle, breathing and heartbeat frequency, micro-Doppler and motion trajectory;

[0138] In the fourth working mode, the radar divides time windows to detect targets, and if the expected target is detected in a time window, the next time window is entered to continue detecting whether the expected target exists, the expected target including the first target, the second target and the third target, the first target set containing the second target, and the second target set containing the third target.

[0139] The specific implementation of each operation can refer to the foregoing embodiments, and will not be described here.

[0140] The storage medium can include a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0141] Since the instructions stored in the storage medium can execute the steps of any radar target detection method provided by the embodiments of the present application, the beneficial effects of any radar target detection method provided by the embodiments of the present application can be achieved, which will be described in detail in the foregoing embodiments, and will not be described here.

[0142] The above describes in detail the radar target detection method, device, terminal and storage medium provided by the embodiments of the present application. The specific examples are applied to describe the principles and implementation modes of the present application. The above description of the embodiments is only used to help understand the method and core idea of the present application. Meanwhile, for those skilled in the art, the specific implementation modes and application ranges can be changed according to the idea of the present application. In summary, the content of the specification should not be understood as a limitation of the present application.

Claims

1. A method of target detection for a radar, wherein, The method comprises: starting a first working mode of the radar, starting a second working mode of the radar when a first type of target is detected; detecting a second type of target within a first preset time period, starting a third working mode of the radar when the second type of target is detected; within a second preset time period, the radar performs multi-dimensional measurement parameter extraction to detect a third type of target, and when the third type of target is detected within the second preset time period, the fourth working mode of the radar is started or the third working mode of the radar is controlled to remain, and the multi-dimensional measurement parameter comprises distance, speed, angle, breathing and heartbeat frequency, micro-Doppler and motion trajectory; in the fourth working mode, the radar divides a time window to detect a target, and if an expected target is detected in a time window, the next time window is entered to continue detecting whether the expected target exists, and the expected target comprises the first type of target, the second type of target and the third type of target, the first type of target set contains the second type of target, and the second type of target set contains the third type of target.

2. The target detection method of a radar according to claim 1, wherein, After starting the first working mode of the radar, the method further comprises: periodically transmitting a first frame format probe signal, and detecting the first type of target according to a received signal; if the radar is a range radar, generating a distance spectrum according to a received signal of each frame, and detecting the first type of target on the distance spectrum; if the radar is a Doppler radar, generating a speed spectrum according to a received signal of each frame, and detecting the first type of target on the speed spectrum.

3. The target detection method of a radar according to claim 1, wherein, After starting the second working mode of the radar, the method further comprises: transmitting multiple second frame format probe signals, and performing weighted combination on data with the same sampling point number in all received signals to obtain a combined signal, wherein the transmitted second frame format probe signals are arranged at unequal intervals in time; if the radar is a range radar, generating a distance spectrum according to the combined signal, and detecting the second type of target on the distance spectrum; if the radar is a Doppler radar, calculating an energy value of the combined signal, and detecting the second type of target according to a comparison result of the energy value and an energy threshold value.

4. The target detection method of a radar according to claim 1, wherein, After starting the second working mode of the radar, the method further comprises: transmitting multiple second frame format probe signals, and performing front-back difference processing on all received signals according to a receiving sequence to obtain multiple difference signals, wherein the transmitted second frame format probe signals are arranged at unequal intervals in time; if the radar is a range radar, generating multiple distance spectra according to the multiple difference signals, and detecting the second type of target according to a number of targets detected from the multiple distance spectra; if the radar is a Doppler radar, calculating energy values of the multiple difference signals, and detecting the second type of target according to a number of energy values exceeding an energy threshold value.

5. The target detection method of a radar according to claim 1, wherein, The radar performs multi-dimensional measurement parameter extraction, comprising: periodically transmitting a third frame format probe signal and receiving a corresponding echo signal; if the radar is a range radar, generating a distance-speed spectrum according to multiple received echo signals corresponding to the same frame, and obtaining the multi-dimensional measurement parameter based on multiple distance-speed spectra; If the radar is a Doppler radar, velocity spectra are generated from a plurality of received echo signals corresponding to the same frame, and the multi-dimensional measurement parameters are obtained based on the plurality of velocity spectra.

6. The target detection method of a radar as claimed in claim 1, wherein, The radar divides time windows for target detection, including: All echo signals received by the radar in the current time window are jointly processed for target detection, and the joint processing includes the following: All echo signals are subjected to two-dimensional Fourier transform to obtain a range-velocity spectrum; or, Data with the same sample point number in all echo signals are arithmetically averaged, and a range spectrum is calculated based on the arithmetically averaged data; or, Data with the same sample point number in all echo signals are weighted and combined to obtain a combined signal, and a range spectrum is generated based on the combined signal; or, All echo signals are subjected to forward-backward difference processing according to the order of reception to obtain a plurality of difference signals, and a range spectrum is calculated for each of the plurality of difference signals to obtain a plurality of range spectra.

7. The method of target detection of a radar according to any one of claims 1 to 6, wherein, After detecting the target in the second and fourth working modes, the method further includes: Obtaining angle information of the detected target, the angle information including horizontal angle, azimuth angle and pitch angle; Determining whether the angle information is within a preset range; If yes, it is confirmed that the detected target is the expected target in the current working mode, and if no, it is not the expected target in the current working mode, wherein in the second working mode, the expected target refers to the second type of target, and in the fourth working mode, the expected target includes the first type of target, the second type of target and the third type of target.

8. A target detection apparatus for a radar, wherein, including: A first detection unit for starting a first working mode of the radar, and starting a second working mode of the radar when a first type of target is detected; A second detection unit for detecting a second type of target within a first preset time period, and starting a third working mode of the radar when the second type of target is detected; A third detection unit for extracting multi-dimensional measurement parameters of the radar within a second preset time period, detecting a third type of target, and starting a fourth working mode of the radar or controlling the radar to remain in the third working mode when the third type of target is detected within the second preset time period, the multi-dimensional measurement parameters including range, velocity, angle, respiratory and heartbeat frequency, micro-Doppler and motion trajectory; A fourth detection unit for dividing time windows for target detection by the radar in the fourth working mode, and entering the next time window to continue detecting whether the expected target exists if the expected target is detected in a time window, the expected target including the first type of target, the second type of target and the third type of target, the set of the first type of target containing the second type of target, and the set of the second type of target containing the third type of target.

9. A terminal, wherein, The terminal includes a memory and a processor, wherein the memory stores an application processing program, and the application processing program is executed by the processor to implement the steps of the target detection method of the radar according to any one of claims 1 to 7.

10. A computer readable storage medium, wherein, The storage medium stores a plurality of instructions, and the instructions are adapted to be loaded by the processor to execute the target detection method of the radar according to any one of claims 1 to 7.

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