Life detection methods, devices, radar, and storage media

Abstract

This invention provides a method, apparatus, radar, and storage medium for detecting living organisms, comprising: acquiring radar data of the current frame; obtaining a one-dimensional array corresponding to the radar data of the current frame through preset processing steps; placing the one-dimensional array corresponding to the radar data of the current frame into a preset sliding window, the sliding window being used to store one-dimensional arrays corresponding to radar data of the most recent consecutive first preset number of frames, the current data in the sliding window constituting the still frame data of the current moment; if the target living organism is in motion at the current moment, outputting a point cloud map corresponding to the radar data of the current frame; if the target living organism is in a stationary state at the current moment, outputting a point cloud map corresponding to the still frame data of the current moment; and detecting the target living organism based on the output point cloud map. This method can simultaneously detect living organisms in both stationary and moving states.

Description

Technical Field

[0001] This invention relates to the field of radar detection technology, and in particular to a method, device, radar, and storage medium for detecting living organisms. Background Technology

[0002] With the continuous increase in radar bandwidth and the number of transceiver channels, the ranging and angular resolution of radar are also constantly improving. This allows radar to acquire richer point cloud information, such as obtaining point clouds of living organisms to reveal their morphology.

[0003] Taking the human body as an example, traditional radar detection procedures are only suitable for acquiring point clouds of moving human bodies. When the human body is stationary and only breathing is involved, radar cannot acquire point clouds.

[0004] Therefore, how to detect living organisms in a stationary state using existing radar is a technical problem that needs to be solved. Summary of the Invention

[0005] In view of this, the present invention provides a method, device, radar and storage medium for detecting living organisms, which can solve the problem that radar cannot detect living organisms in a stationary state.

[0006] In a first aspect, embodiments of the present invention provide a method for detecting living organisms. This method is applied to a radar, wherein the radar's transmitting antenna transmits continuous wave signals frame by frame, and the number of continuous wave signals in one frame is N. c Each echo signal received by the radar's receiving antenna is processed to obtain N corresponding to that echo signal. s For N discrete points, for one receiving channel of the radar, the radar data received by the receiving channel in one frame is N. s * c A two-dimensional matrix, or N c * s The method includes: a two-dimensional matrix.

[0007] The radar data of the current frame is acquired, and a one-dimensional array corresponding to the radar data of the current frame is obtained through preset processing steps. The one-dimensional array corresponding to the radar data of the current frame is then placed into a preset sliding window. The preset processing steps involve selecting N corresponding to the same discrete point in a frame of radar data. c Summing the data points yields a data volume of N. s The one-dimensional array, the sliding window is a preset storage space, the sliding window is used to store the one-dimensional array corresponding to the radar data of the first preset number of consecutive frames closest to the current time, and the current data in the sliding window constitutes the still frame data of the current time;

[0008] If the target life form is in motion at the current moment, the point cloud map corresponding to the radar data of the current frame will be output; if the target life form is stationary at the current moment, the point cloud map corresponding to the stationary frame data of the current moment will be output.

[0009] The target life form is detected based on the output point cloud map.

[0010] In one possible implementation, the process of determining the current state of the target life form includes:

[0011] The radar data of the current frame is processed to obtain the point cloud map corresponding to the radar data of the current frame;

[0012] Based on the point cloud map corresponding to the radar data of the current frame, the number of moving point clouds in the current frame is obtained, wherein the moving point cloud is used to represent the point cloud with a velocity not equal to 0.

[0013] Based on the number of moving point clouds in the current frame, the state of the target life form at the current moment is determined, and the state of the target life form at the current moment is either in motion or at rest.

[0014] In one possible implementation, determining the state of the target life form at the current moment based on the number of motion point clouds in the current frame includes:

[0015] If the number of moving point clouds in the current frame is greater than a preset threshold, then the target life form is in motion.

[0016] If the number of moving point clouds in the current frame is less than or equal to a preset threshold, the target life form is in a static state.

[0017] In one possible implementation, the radar is a multiple-input multiple-output (MIMO) radar, and the number of equivalent virtual channels of the MIMO radar is N. r The method for determining the state of the target life form at the current moment based on the number of motion point clouds in the current frame includes:

[0018] In the N r In the equivalent virtual channel, if there is at least one channel with a number of moving point clouds in the current frame that is greater than a first preset value, then it is determined that the target life form is in motion at the current moment.

[0019] Or, in the N r In the equivalent virtual channel, if there is a preset number of channels in the current frame whose number of moving point clouds is greater than a second preset value, then it is determined that the target life form is in motion at the current moment.

[0020] Or, in the N rIn the equivalent virtual channel, if the average number of moving point clouds in each channel in the current frame is greater than a third preset value, then it is determined that the target life form is in motion at the current moment, wherein the first preset value is greater than the second preset value, and the first preset value is greater than the third preset value.

[0021] In one possible implementation, for any frame of data, which can be either a radar frame or a still frame, the process of obtaining the point cloud map corresponding to that frame of data includes:

[0022] Perform a two-dimensional fast Fourier transform on the frame data to obtain the range Doppler RD map corresponding to the frame data;

[0023] The constant false alarm rate (CFAR) detection was performed on the RD map corresponding to the frame data to obtain multiple detection points.

[0024] Angle measurements are performed at each detection point to obtain the distance, azimuth, and pitch angles of each point cloud.

[0025] In one possible implementation, the continuous wave signal is a chirp signal, and each echo signal received by the radar's receiving antenna is processed to obtain the N corresponding to that echo signal. s The discrete points include:

[0026] Each echo signal received by the radar receiving antenna is down-converted, filtered, and sampled to obtain a digital echo signal;

[0027] Perform a one-dimensional fast Fourier transform on the digital echo signal to obtain N. s A discrete point.

[0028] In one possible implementation, detecting the target life form based on the output point cloud map includes:

[0029] The target life form is detected based on the point cloud map of the second consecutive preset number of frames output.

[0030] Secondly, embodiments of the present invention provide a life form detection device, which is applied to a radar, wherein the radar's transmitting antenna transmits continuous wave signals frame by frame, and the number of continuous wave signals in one frame is N. c Each echo signal received by the radar's receiving antenna is processed to obtain N corresponding to that echo signal. s For N discrete points, for one receiving channel of the radar, the radar data received by the receiving channel in one frame is N. s * c A two-dimensional matrix, or N c * sThe two-dimensional matrix includes: a data acquisition module, an output module, and a detection module;

[0031] The data acquisition module is used to acquire radar data of the current frame, obtain a one-dimensional array corresponding to the radar data of the current frame through preset processing steps, and place the one-dimensional array corresponding to the radar data of the current frame into a preset sliding window. The preset processing steps involve selecting N corresponding to the same discrete point in a frame of radar data. c Summing the data points yields a data volume of N. s The one-dimensional array, the sliding window is a preset storage space, the sliding window is used to store the one-dimensional array corresponding to the radar data of the first preset number of consecutive frames closest to the current time, and the current data in the sliding window constitutes the still frame data of the current time;

[0032] The output module is used to output the point cloud map corresponding to the radar data of the current frame if the target life form is in motion at the current moment, and to output the point cloud map corresponding to the static frame data of the current moment if the target life form is in a stationary state at the current moment.

[0033] The detection module is used to detect the target life form based on the output point cloud map.

[0034] Thirdly, embodiments of the present invention provide a radar, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method as described in the first aspect or any possible implementation of the first aspect above.

[0035] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method as described in the first aspect or any possible implementation thereof.

[0036] The beneficial effects of the embodiments of the present invention compared with the prior art are as follows:

[0037] This invention obtains a one-dimensional array by summing multiple data points corresponding to the same discrete point in the radar data of normal frames. The one-dimensional array corresponding to the radar data of the most recent consecutive normal frames at the current time is accumulated to construct still frame data. Based on the state of the target life form at the current time, when the target life form is in motion, the radar data of the current frame is output, and when the target life form is in a stationary state, the still frame data is output. This realizes normal detection of the target life form in motion, and when the target life form is stationary, the method of constructing still frame data extends the time in the velocity dimension, which is equivalent to improving the radar resolution and realizing the detection of the target life form in a stationary state. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a flowchart illustrating the implementation of the life form detection method provided in this embodiment of the invention;

[0040] Figure 2 This is a signal form diagram of a chirp signal provided in an embodiment of the present invention;

[0041] Figure 3 This is a schematic diagram of the living organism detection device provided in an embodiment of the present invention;

[0042] Figure 4 This is a schematic diagram of the radar provided in an embodiment of the present invention. Detailed Implementation

[0043] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0044] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0045] Radar transmits signals in frames, processing each frame only once. The frame period of a radar is typically in the tens of milliseconds (ms), which limits its velocity resolution. This means that radar cannot detect targets with velocity resolutions lower than its maximum. Generally, when radar detects a living organism—for example, a human—the rate of human breathing is slow and below the radar's velocity resolution. Therefore, traditional radar point cloud-based detection processes can only detect moving human bodies, not stationary ones.

[0046] Typically, the method provided in this embodiment of the invention is applied to the detection of human bodies in smart home scenarios, or to the detection of target living beings in enclosed spaces, such as detecting target living beings inside a vehicle to prevent children from being left inside. The above are merely examples of typical application scenarios of the method provided in this embodiment of the invention, and are not intended to limit it.

[0047] See Figure 1 The flowchart illustrating the implementation of the life form detection method provided in this embodiment of the invention is described in detail below:

[0048] In step 101, the radar data of the current frame is acquired, and a one-dimensional array corresponding to the radar data of the current frame is obtained through preset processing steps. The one-dimensional array corresponding to the radar data of the current frame is then placed into a preset sliding window. The preset processing steps involve taking the N corresponding to the same discrete point in a frame of radar data. c Summing the data points yields a data volume of N. s The one-dimensional array is a sliding window that serves as a preset storage space. The sliding window stores the one-dimensional array corresponding to the radar data of the first preset number of consecutive frames closest to the current time. The current data in the sliding window constitutes the still frame data of the current time.

[0049] The method provided in this embodiment of the invention is applied to radar, where the radar's transmitting antenna transmits continuous wave signals frame by frame, and the number of continuous wave signals in one frame is N. c Each echo signal received by the radar's receiving antenna is processed to obtain the N corresponding to that echo signal. s For N discrete points, for one receiving channel of the radar, the radar data received by that receiving channel is N frames. s * c A two-dimensional matrix, or N c * s A two-dimensional matrix.

[0050] In some embodiments of the present invention, the radar referred to is a millimeter-wave radar, and the detection signal transmitted by the millimeter-wave radar transmitting antenna is an FMCW (Frequency Modulated Continuous Wave) signal. FMCW technology is a technique used in high-precision radar ranging. Its basic principle is that the transmitted wave is a high-frequency continuous wave, and its frequency changes with time according to a triangular wave law. The frequency of the echo received by FMCW changes in the same way as the transmitted frequency, both following a triangular wave law, but with a time difference. The target distance can be calculated using this small time difference.

[0051] The transmitting antenna transmits one frame of FMCW signal, and the receiving antenna receives one frame of the corresponding radar echo signal. The received radar echo signal is preprocessed to obtain a digital echo signal.

[0052] Generally, the signal model uses chirp signals. Figure 2 This is a signal form diagram of a chirp signal provided in an embodiment of the present invention, combined with... Figure 2f0 is the starting frequency of the transmitted signal, B is the frequency modulation bandwidth, Tc is the duration of one chirp, and Tf is the time interval between two transmitted frames, also known as the frame period. The number of chirp signals in one frame is N. c indivual.

[0053] In one alternative implementation, the continuous wave signal is a chirp signal. After the radar receiving antenna receives the echo signal, each echo signal received by the radar receiving antenna is down-converted, filtered, and sampled to obtain a digital echo signal. A one-dimensional fast Fourier transform is then performed on the digital echo signal to obtain N. s There are discrete points, where the frame period Tf of the chirp signal is and the sampling rate is f. s .

[0054] Therefore, the size of each frame of radar data is Ns*Nc.

[0055] In this embodiment of the invention, a preset storage space is set as a preset sliding window, the size of which is Ns*Nm, where Nm is the first preset number of frames. In an optional implementation, the initialization value of the sliding window is all 0. After initialization, after obtaining the first frame of radar data, the N values ​​corresponding to the same discrete point in the first frame of radar data are... c Summing the data points yields a data volume of N. s A one-dimensional array is placed into the preset sliding window, for example, arranged by column. The first one-dimensional array is placed in the first column of the sliding window. After obtaining the second frame of radar data, the N corresponding to the same discrete point in the second frame of radar data is analyzed. c Summing the data points yields a data volume of N. s A one-dimensional array is placed into the preset sliding window and positioned in the second column of the window; following the same method, the N corresponding to the same discrete point in the Nm-th frame of radar data is... c Summing the data points yields a data volume of N. s After the one-dimensional array is processed, it is placed into the last column of the sliding window. At this point, the sliding window is full, and initialization is complete. After initialization, each new frame of radar data is used as the current frame radar data. The N values ​​corresponding to the same discrete point in the current frame radar data are then used. c Summing the data points yields a data volume of N. s After the one-dimensional array, the original first column of data in the sliding window is slid out, that is, removed from the sliding window. The original second to Nm columns each slide forward one column. Then, the one-dimensional array corresponding to the radar data of the current frame is put into the last column of the sliding window. At this time, the Ns*Nm two-dimensional array in the sliding window constitutes the still frame data of the current moment.

[0056] For example, the still frame data is a two-dimensional array of Ns*Nm. For the same discrete point in a frame of radar data, N...c The process of summing up the data is shown in Formula 1. Formula 1 is:

[0057]

[0058] Where dataAcc(i) is the N corresponding to the i-th discrete point. c The summation of the data points results in a single frame of radar data in dataCube. dataCube(i,n) represents the N values ​​corresponding to the i-th discrete point in a single frame of radar data. c The nth data point in a set of data points, whose accumulated dataAcc is a data set of N data points. s A one-dimensional array can be represented by dataAcc(1:Ns).

[0059] The sliding window stores a one-dimensional array corresponding to the radar data of the first preset number of consecutive frames closest to the current time, that is, the specific method for storing a one-dimensional array corresponding to the radar data of Nm consecutive frames is shown in Formulas 2 and 3 below. Formula 2 is:

[0060] dataCubeStatic(1:Ns,1:Nm-1)=dataCubeStatic(1:Ns,2:Nm)

[0061] dataCubeStatic is used to represent still frame data, which is the data stored in the sliding window. It is a two-dimensional array of Ns*Nm.

[0062] The following explanation uses a two-dimensional array of dataCubeStatic with Ns rows and Nm columns as an example.

[0063] The `dataCubeStatic(1:Ns,1:Nm-1)` function represents the data from the first column to the Nm-1th column in the sliding window, which is the data from the first Nm-1th column. The `dataCubeStatic(1:Ns,2:Nm)` function represents the data from the second column to the Nmth column in the sliding window. The process corresponding to Formula 2 is to slide out the original first column of data from the sliding window after obtaining the one-dimensional array corresponding to the new frame of radar data, that is, to remove it from the sliding window, and slide the original second column to the Nmth column forward by one column.

[0064] Formula 3 is:

[0065] dataCubeStatic(1:Ns,Nm)=dataAcc(1:Ns)

[0066] The dataCubeStatic(1:Ns,Nm) is used to represent the last column of data in the sliding window. When a new frame of radar data is obtained, the new frame of radar data is used as the one-dimensional array corresponding to the current frame of radar data, which is dataAcc(1:Ns). Formula 3 is used to represent the process of putting the one-dimensional array corresponding to the current frame of radar data into the last column of the sliding window.

[0067] The data obtained from Formulas 2 and 3 in the sliding window is the still frame data at the current moment.

[0068] The method provided in this invention obtains the data in the sliding window as still frame data, which is equivalent to lengthening the time in the velocity dimension, improving the velocity resolution of the radar, and thus the still frame data can be used to detect living beings in a stationary state, such as the human body.

[0069] In step 102, if the target life form is in motion at the current moment, the point cloud map corresponding to the radar data of the current frame is output; if the target life form is stationary at the current moment, the point cloud map corresponding to the stationary frame data of the current moment is output.

[0070] The state of the target life form at the current moment can include a moving state and a stationary state. The stationary state and the slightly moving state are used to represent the same state. Optionally, the state of the target life form at the current moment can be determined based on the number of moving point clouds in the point cloud map corresponding to the radar data of the current frame. Alternatively, the state of the target life form at the current moment can be predicted based on radar data of a preset number of frames before the current frame. This embodiment of the invention does not limit this.

[0071] In one optional implementation, the radar data of the current frame is processed to obtain the point cloud map corresponding to the radar data of the current frame; based on the point cloud map corresponding to the radar data of the current frame, the number of moving point clouds in the current frame is obtained, wherein the moving point clouds are used to represent point clouds with a velocity not equal to 0; based on the number of moving point clouds in the current frame, the state of the target life form at the current moment is determined, and the state of the target life form at the current moment is either in motion or at rest.

[0072] In one optional implementation, determining the state of the target life form at the current moment based on the number of moving point clouds in the current frame includes: if the number of moving point clouds in the current frame is greater than a preset threshold, the target life form is in motion; if the number of moving point clouds in the current frame is less than or equal to the preset threshold, the target life form is in a stationary state.

[0073] In one optional implementation, the radar referred to in this embodiment of the invention is a millimeter-wave radar, and the millimeter-wave radar is a multiple-input multiple-output (MIMO) millimeter-wave radar, which includes a T... x One transmitting antenna and Rx With one receiving antenna, the equivalent virtual channel number of the millimeter-wave radar is N. r =T x *R x .

[0074] In one possible implementation, in N r In the equivalent virtual channel, if at least one channel has a number of moving point clouds in the current frame greater than a first preset value, then the target life form is determined to be in motion at the current moment; or, in N... r In the equivalent virtual channel of the path, if there exists a preset number of channels whose number of moving point clouds in the current frame is greater than a second preset value, then it is determined that the target life form is in motion at the current moment; or, in N r In the equivalent virtual channel, if the average number of moving point clouds in each channel in the current frame is greater than the third preset value, then it is determined that the target life form is in motion at the current moment. The first preset value is greater than the second preset value, and the first preset value is greater than the third preset value.

[0075] In one optional implementation, for any frame of data, which may be a radar frame or a stationary frame, the process of obtaining the point cloud map corresponding to that frame of data includes: performing a two-dimensional fast Fourier transform on the frame of data to obtain the range Doppler (RD) map corresponding to that frame of data; performing constant false alarm rate (CFAR) detection on the RD map corresponding to that frame of data to obtain multiple detection points; and measuring the angles of each detection point to obtain the range, azimuth, and elevation angles of each point cloud.

[0076] In step 103, the target life form is detected based on the output point cloud map.

[0077] In one embodiment of the invention, optionally, the target life form can be detected based on the point cloud map output in the current frame, or it can be detected based on the point cloud map output for a consecutive second preset number of frames, where the consecutive second preset number of frames includes the current frame. This embodiment of the invention does not impose any limitations on this method.

[0078] This invention obtains a one-dimensional array by summing multiple data points corresponding to the same discrete point in the radar data of normal frames. The one-dimensional array corresponding to the radar data of the most recent consecutive normal frames at the current time is accumulated to construct still frame data. Based on the state of the target life form at the current time, when the target life form is in motion, the radar data of the current frame is output, and when the target life form is in a stationary state, the still frame data is output. This realizes normal detection of the target life form in motion, and when the target life form is stationary, the method of constructing still frame data extends the time in the velocity dimension, which is equivalent to improving the radar resolution and realizing the detection of the target life form in a stationary state.

[0079] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0080] The following are device embodiments of the present invention. For details not described in detail, please refer to the corresponding method embodiments described above.

[0081] Figure 3 A schematic diagram of the living organism detection device provided in an embodiment of the present invention is shown. For ease of explanation, only the parts related to the embodiment of the present invention are shown, and are described in detail below:

[0082] like Figure 3 As shown, the life detection device 3 includes: a data acquisition module 31, an output module 32, and a detection module 33;

[0083] This device is used in a radar where the transmitting antenna transmits continuous wave signals frame by frame, and the number of continuous wave signals in one frame is N. c Each echo signal received by the radar's receiving antenna is processed to obtain N corresponding to that echo signal. s For N discrete points, for one receiving channel of the radar, the radar data received by that receiving channel is N frames. s * c A two-dimensional matrix, or N c * s A two-dimensional matrix.

[0084] Data acquisition module 31 is used to acquire radar data of the current frame, obtain a one-dimensional array corresponding to the radar data of the current frame through preset processing steps, and put the one-dimensional array corresponding to the radar data of the current frame into a preset sliding window. The preset processing steps are to extract N corresponding to the same discrete point in a frame of radar data. c Summing the data points yields a data volume of N. s A one-dimensional array, with a sliding window as a preset storage space. The sliding window is used to store the one-dimensional array corresponding to the radar data of the first preset number of consecutive frames closest to the current time. The current data in the sliding window constitutes the still frame data of the current time.

[0085] The output module 32 is used to output the point cloud map corresponding to the radar data of the current frame if the target life form is in motion at the current moment, and to output the point cloud map corresponding to the stationary frame data of the current moment if the target life form is stationary at the current moment.

[0086] The detection module 33 is used to detect the target life form based on the output point cloud map.

[0087] This invention obtains a one-dimensional array by summing multiple data points corresponding to the same discrete point in the radar data of normal frames. The one-dimensional array corresponding to the radar data of the most recent consecutive normal frames at the current time is accumulated to construct still frame data. Based on the state of the target life form at the current time, when the target life form is in motion, the radar data of the current frame is output, and when the target life form is in a stationary state, the still frame data is output. This realizes normal detection of the target life form in motion, and when the target life form is stationary, the method of constructing still frame data extends the time in the velocity dimension, which is equivalent to improving the radar resolution and realizing the detection of the target life form in a stationary state.

[0088] In one possible implementation, output module 32 is used for:

[0089] The radar data of the current frame is processed to obtain the point cloud map corresponding to the radar data of the current frame;

[0090] Based on the point cloud map corresponding to the radar data of the current frame, obtain the number of moving point clouds in the current frame, where moving point clouds are used to represent point clouds with non-zero velocity;

[0091] Based on the number of moving point clouds in the current frame, the state of the target life form at the current moment is determined, and the state of the target life form at the current moment is either in motion or at rest.

[0092] In one possible implementation, output module 32 is used for:

[0093] If the number of moving point clouds in the current frame is greater than a preset threshold, the target life form is in motion.

[0094] If the number of moving point clouds in the current frame is less than or equal to a preset threshold, the target life form is in a static state.

[0095] In one possible implementation, the radar is a multiple-input multiple-output (MIMO) radar, and the number of equivalent virtual channels of the MIMO radar is N. r Based on the number of moving point clouds in the current frame, the output module 32 is used for:

[0096] In N r In the equivalent virtual channel, if there is at least one channel with a number of moving point clouds in the current frame that is greater than the first preset value, then it is determined that the target life form is in motion at the current moment.

[0097] Or, in N r In the equivalent virtual channel of the road, if there is a channel with a number of motion point clouds greater than or equal to a preset number in the current frame, the target life form is determined to be in motion at the current moment.

[0098] Or, in Nr In the equivalent virtual channel, if the average number of moving point clouds in each channel in the current frame is greater than the third preset value, then it is determined that the target life form is in motion at the current moment. The first preset value is greater than the second preset value, and the first preset value is greater than the third preset value.

[0099] In one possible implementation, for any frame of data, which can be either a radar frame or a stationary frame, the output module 32 is used for:

[0100] Perform a two-dimensional fast Fourier transform on the frame data to obtain the range Doppler RD map corresponding to the frame data;

[0101] The constant false alarm rate (CFAR) detection was performed on the RD map corresponding to the frame data to obtain multiple detection points.

[0102] Angle measurements are performed at each detection point to obtain the distance, azimuth, and pitch angles of each point cloud.

[0103] In one possible implementation, the continuous wave signal is a chirp signal, and the data acquisition module 31 is further used for:

[0104] Each echo signal received by the radar receiving antenna is down-converted, filtered, and sampled to obtain a digital echo signal;

[0105] Perform a one-dimensional fast Fourier transform on the digital echo signal to obtain N. s A discrete point.

[0106] In one possible implementation, the detection module 33 is used to detect the target life form based on the point cloud map of the output consecutive second preset number of frames.

[0107] The life form detection device provided in this embodiment can be used to execute the above-described life form detection method embodiment. Its implementation principle and technical effect are similar, and will not be described again here.

[0108] Figure 4 This is a schematic diagram of a radar provided according to an embodiment of the present invention. Figure 4 As shown, the radar 4 in this embodiment includes: a processor 40, a memory 41, and a computer program 42 stored in the memory 41 and executable on the processor 40. When the processor 40 executes the computer program 42, it implements the steps in the various life form detection method embodiments described above, for example... Figure 1 Steps 101 to 103 are shown. Alternatively, when the processor 40 executes the computer program 42, it implements the functions of each module / unit in the above-described device embodiments, for example... Figure 3 The functions of modules 31 to 33 are shown.

[0109] For example, the computer program 42 can be divided into one or more modules / units, which are stored in the memory 41 and executed by the processor 40 to complete the present invention. The one or more modules / units can be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program 42 in the radar 4.

[0110] The radar 4 may be a millimeter-wave radar. The radar 4 may include, but is not limited to, a processor 40 and a memory 41. Those skilled in the art will understand that... Figure 4 This is merely an example of radar 4 and does not constitute a limitation on radar 4. It may include more or fewer components than shown, or combine certain components, or different components. For example, the radar may also include input / output devices, network access devices, buses, etc.

[0111] The processor 40 can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor.

[0112] The memory 41 can be an internal storage unit of the radar 4, such as a hard disk or memory of the radar 4. The memory 41 can also be an external storage device of the radar 4, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the radar 4. Furthermore, the memory 41 can include both internal storage units and external storage devices of the radar 4. The memory 41 is used to store the computer program and other programs and data required by the radar. The memory 41 can also be used to temporarily store data that has been output or will be output.

[0113] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0114] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0115] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0116] In the embodiments provided by this invention, it should be understood that the disclosed apparatus / radar and method can be implemented in other ways. For example, the apparatus / radar embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0117] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0118] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0119] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various life form detection method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0120] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for detecting living organisms, characterized in that, This method is applied to radar, where the transmitting antenna transmits continuous wave signals frame by frame, and the number of continuous wave signals in one frame is... Each echo signal received by the radar's receiving antenna is processed to obtain the corresponding echo signal. For a discrete point, and for one receiving channel of the radar, a frame of radar data received by that receiving channel is: A two-dimensional matrix, or a The method includes: a two-dimensional matrix. The radar data of the current frame is acquired, and a one-dimensional array corresponding to the radar data of the current frame is obtained through preset processing steps. This one-dimensional array is then placed into a preset sliding window. The preset processing steps are based on… The corresponding discrete point in a frame of radar data Summing the data points yields a data volume of . A one-dimensional array; where, For the first The corresponding discrete points The value obtained by summing the data. Used to represent the i-th discrete point in a frame of radar data The nth data in a set of data; The sliding window is a preset storage space, and the sliding window is used to... and A one-dimensional array is stored corresponding to the radar data of the first preset number of consecutive frames most recent to the current time. The current data in the sliding window constitutes the still frame data of the current time. Used to represent the first column to the second column in a sliding window. The data in the column, Used to indicate the 2nd to 3rd columns in the sliding window The data in the column, The data used to represent the last column of data in the sliding window. ; If the target life form is in motion at the current moment, the point cloud map corresponding to the radar data of the current frame will be output; if the target life form is stationary at the current moment, the point cloud map corresponding to the stationary frame data of the current moment will be output. The target life form is detected based on the output point cloud map.

2. The method according to claim 1, characterized in that, The process of determining the current state of the target life form includes: The radar data of the current frame is processed to obtain the point cloud map corresponding to the radar data of the current frame; Based on the point cloud map corresponding to the radar data of the current frame, the number of moving point clouds in the current frame is obtained, wherein the moving point cloud is used to represent the point cloud with a velocity not equal to 0. Based on the number of moving point clouds in the current frame, the state of the target life form at the current moment is determined, and the state of the target life form at the current moment is either in motion or at rest.

3. The method according to claim 2, characterized in that, Determining the state of the target life form at the current moment based on the number of motion point clouds in the current frame includes: If the number of moving point clouds in the current frame is greater than a preset threshold, then the target life form is in motion. If the number of moving point clouds in the current frame is less than or equal to a preset threshold, the target life form is in a static state.

4. The method according to claim 2, characterized in that, The radar is a multiple-input multiple-output (MIMO) radar, and the number of equivalent virtual channels of the MIMO radar is: The method for determining the state of the target life form at the current moment based on the number of motion point clouds in the current frame includes: In the In the equivalent virtual channel, if the number of moving point clouds in the current frame of at least one channel is greater than the first preset value, then it is determined that the target life form is in motion at the current moment. Or, in the In the equivalent virtual channel, if there is a preset number of channels in the current frame whose number of moving point clouds is greater than a second preset value, then it is determined that the target life form is in motion at the current moment. Or, in the In the equivalent virtual channel, if the average number of moving point clouds in each channel in the current frame is greater than a third preset value, then it is determined that the target life form is in motion at the current moment, wherein the first preset value is greater than the second preset value and the first preset value is greater than the third preset value.

5. The method according to any one of claims 1 to 4, characterized in that, For any frame of data, which may be a radar frame or a still frame, the process of obtaining the point cloud map corresponding to that frame of data includes: Perform a two-dimensional fast Fourier transform on the frame data to obtain the range Doppler RD map corresponding to the frame data; The constant false alarm rate (CFAR) detection was performed on the RD map corresponding to the frame data to obtain multiple detection points. Angle measurements are performed at each detection point to obtain the distance, azimuth, and pitch angles of each point cloud.

6. The method according to any one of claims 1 to 4, characterized in that, The continuous wave signal is a chirp signal. Each echo signal received by the radar's receiving antenna is processed to obtain the corresponding echo signal. The discrete points include: Each echo signal received by the radar receiving antenna is down-converted, filtered, and sampled to obtain a digital echo signal; Perform a one-dimensional fast Fourier transform on the digital echo signal to obtain A discrete point.

7. The method according to any one of claims 1 to 4, characterized in that, The detection of the target life form based on the output point cloud map includes: The target life form is detected based on the point cloud map of the second consecutive preset number of frames output.

8. A living organism detection device, characterized in that, This device is applied to a radar whose transmitting antenna transmits continuous wave signals frame by frame, and the number of continuous wave signals in one frame is... Each echo signal received by the radar's receiving antenna is processed to obtain the corresponding echo signal. For a discrete point, and for one receiving channel of the radar, a frame of radar data received by that receiving channel is: A two-dimensional matrix, or a The two-dimensional matrix includes: a data acquisition module, an output module, and a detection module; The data acquisition module is used to acquire radar data of the current frame, obtain a one-dimensional array corresponding to the radar data of the current frame through preset processing steps, and place the one-dimensional array corresponding to the radar data of the current frame into a preset sliding window. The preset processing steps are based on... The corresponding discrete point in a frame of radar data Summing the data points yields a data volume of . A one-dimensional array; where, For the first The corresponding discrete points The value obtained by summing the data. Used to represent the i-th discrete point in a frame of radar data The nth data in a set of data; The sliding window is a preset storage space, and the sliding window is used to... and A one-dimensional array is stored corresponding to the radar data of the first preset number of consecutive frames most recent to the current time. The current data in the sliding window constitutes the still frame data of the current time. Used to represent the first column to the second column in a sliding window. The data in the column, Used to indicate the 2nd to 3rd columns in the sliding window The data in the column, The data used to represent the last column of data in the sliding window. ; The output module is used to output the point cloud map corresponding to the radar data of the current frame if the target life form is in motion at the current moment, and to output the point cloud map corresponding to the static frame data of the current moment if the target life form is in a stationary state at the current moment. The detection module is used to detect the target life form based on the output point cloud map.

9. A radar comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 7 above.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 7 above.

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