WO2023087232A1

WO2023087232A1 - Radar system and method for detecting pedestrian, and vehicle

Info

Publication number: WO2023087232A1
Application number: PCT/CN2021/131631
Authority: WO
Inventors: 徐江丰; 林春辉; 荆涛
Original assignee: 华为技术有限公司
Priority date: 2021-11-19
Filing date: 2021-11-19
Publication date: 2023-05-25

Abstract

Provided in the present application are a radar system and method for detecting a pedestrian, and a vehicle, which can be applied to the fields of artificial intelligence, autonomous driving, etc. The radar system comprises: an antenna system, which comprises one first transmitting antenna and n second transmitting antennas, wherein the first transmitting antenna is used for identifying a pedestrian, and the n second transmitting antennas are used for determining the position of a potential target; and a processor, which is coupled to the antenna system and is used for controlling, by means of time division multiplexing, the first transmitting antenna and the n second transmitting antennas to transmit detection signals in an interleaved manner, wherein a duty cycle of a first detection signal transmitted by the first transmitting antenna within one transmitting period is located within [1/(n + 1), 1/2], and n is a positive integer. By means of the radar system provided in the solution of the present application, the accuracy of detecting a pedestrian can be improved.

Description

Radar system, method and vehicle for detecting pedestrians

technical field

The present application relates to the field of radar technology, and more particularly, to a radar system, method and vehicle for detecting pedestrians.

Background technique

Millimeter wave radar has the advantages of all-day and all-weather, and is an important sensor in the field of automatic driving and intelligent transportation. In the future, more and more autonomous driving and intelligent transportation systems will use millimeter-wave radar. The important detection target of millimeter-wave radar is pedestrians. Accurate detection of pedestrians is very important to improve the safety level of radar and vehicle or intelligent transportation system.

Existing schemes are usually based on a single input single output (SISO) system to transmit continuous waves, and then determine the position of potential targets based on the returned waveforms, and perform micro-Doppler effect processing on the returned waveforms to judge potential targets. Whether the target is a pedestrian. However, the angle measurement performance of the SISO system is relatively poor, resulting in inaccurate final determined positions of potential targets such as pedestrians, which in turn leads to low accuracy in detecting pedestrians.

Therefore, how to improve the accuracy of detecting pedestrians is a technical problem that needs to be solved urgently.

Contents of the invention

The present application provides a radar system, method and vehicle for detecting pedestrians, which can improve the accuracy of detecting pedestrians.

In a first aspect, a radar system for detecting pedestrians is provided, including: an antenna system including a first transmitting antenna and n second transmitting antennas, wherein the first transmitting antenna is used to identify pedestrians, and the n second transmitting antennas The two transmitting antennas are used to determine the position of the potential target; the processor, coupled to the antenna system, is used to control the first transmitting antenna and the n second transmitting antennas to interleavely transmit detection signals in a time-division multiplexing manner, wherein, The duty cycle of the first detection signal transmitted by the first transmitting antenna within a transmitting period is in [1/(n+1), 1/2], where n is a positive integer.

It should be understood that the use of the first transmitting antenna to identify pedestrians specifically refers to: the echo signal of the detection signal transmitted by the first transmitting antenna is used to identify pedestrians, and it can also be understood as: the echo signal of the detection signal transmitted by the first transmitting antenna can be used to identify pedestrians. signal to identify pedestrians. Hereinafter, the detection signal transmitted by the first transmitting antenna is denoted as the first detection signal, and the echo signal of the first detection signal is denoted as the first echo signal. Similarly, the use of the n second transmitting antennas for determining the position of the potential target specifically means that the echo signals of the detection signals transmitted by the n second transmitting antennas are used to determine the position of the potential target, which can also be understood as: using n The position of the potential target is determined based on the echo signal of the detection signal transmitted by the second transmitting antenna. Hereinafter, the detection signals transmitted by the n second transmitting antennas are denoted as second detection signals, and the echo signals of the second detection signals are denoted as second echo signals.

It should be understood that the first transmitting antenna is used to identify pedestrians mainly by using the micro-Doppler features of the pedestrian in the echo signal of the detection signal transmitted by the first transmitting antenna to identify the pedestrian.

It should be understood that n may be a positive integer greater than or equal to 1.

It should be understood that the duty ratio of the first detection signal transmitted by the first transmitting antenna within one transmitting period may be any value in the interval [1/(n+1), 1/2]. Exemplarily, if n is equal to 1, the duty ratio of the first detection signal in one transmission period may be 1/2; if n is equal to 2, the duty ratio of the first detection signal in one transmission period may be in the interval [ 1/3,1/2]; if n is greater than or equal to 3, the duty cycle of the first detection signal in one transmission period can be in the interval [1/(n+1),1/2] any value in . It should also be understood that the greater the duty cycle of the first detection signal in one transmission cycle, the more the time window for the pedestrian identification detection signal can be ensured, thereby ensuring high-resolution sampling of the micro-Doppler characteristics and improving the micro-Doppler The ability to detect the Le effect, improve and enhance the recognition rate of pedestrians, and ultimately improve the accuracy of pedestrian detection. As a preferred solution, if n is greater than or equal to 3, the duty ratio of the first detection signal in one transmission period can be any value in the interval [1/3, 1/2].

It should be understood that, in this application, the duty cycle refers to the ratio of the time during which the first transmitting antenna transmits the first detection signal to the total time within one pulse cycle.

It should be understood that, while the first transmitting antenna in the present application is used to identify pedestrians, it can also be used together with n second transmitting antennas to determine the position of a potential target, so as to improve the direction of arrival of the antenna in the radar system. DOA) angle measurement performance.

It should be understood that existing solutions are usually based on a single input single output (SISO) system (single input single output, SISO) to transmit a continuous wave, and then determine the position of a potential target based on the returned waveform, and perform micro-Doppler effect processing on the returned waveform, To determine whether the potential target is a pedestrian. However, the angle measurement performance of the SISO system is relatively poor, resulting in inaccurate final determined positions of potential targets such as pedestrians, which in turn leads to low accuracy in detecting pedestrians.

The radar system provided by the embodiment of the present application includes an antenna system and a processor, wherein the antenna system includes a first transmitting antenna and n second transmitting antennas, and the first transmitting antenna is used to identify pedestrians, and the n second transmitting antennas It is used to determine the position of the potential target; wherein, the processor is used to control the first transmitting antenna and n second transmitting antennas to transmit detection signals interleavedly in a time-division multiplexing manner, and the first detection signal transmitted by the first transmitting antenna is within one The duty cycle in the transmission cycle is located at [1/(n+1),1/2], so that while using a single antenna to detect pedestrians, the position of the potential target can be detected in conjunction with n second transmission antennas, so as to Improve the angle measurement performance of the radar system, which in turn can improve the accuracy of pedestrian detection.

It should be understood that since the MIMO system has better angle measurement performance, in the embodiment of the present application, the n second transmit antennas may be located in the MIMO system, so that the angle measurement performance of the MIMO system can be used to improve the Angular performance of radar systems.

With reference to the first aspect, in some implementation manners of the first aspect, the antenna system further includes: a controller, configured to adjust a duty cycle of the first detection signal within a transmission period.

The antenna system of the radar system provided in the embodiment of the present application may also include a controller, which can be used to adjust the duty cycle of the first detection signal in one transmission period, so that in actual operation, the The duty ratio of the first detection signal is flexibly adjusted, so that the wideness of application scenarios of the radar system can be improved. For example, in a scene with higher requirements for identifying pedestrians, the duty cycle of the first detection signal can be appropriately increased; in a scene with higher requirements for angle measurement performance, the duty cycle of the first detection signal can be appropriately reduced Compare.

It should be understood that the controller adjusts the duty cycle of the first detection signal in one transmission period, which means that the controller controls the first detection signal in one transmission period according to actual needs in the interval [1/(n+1),1/2]. The duty cycle within the period is adjusted.

With reference to the first aspect, in some implementation manners of the first aspect, the processor is further configured to acquire a first echo signal of a first detection signal transmitted by the first transmitting antenna and a signal transmitted by the n second transmitting antennas. the second echo signal of the second detection signal; detecting pedestrians according to the first echo signal and the second echo signal.

In the radar system provided by the embodiment of the present application, the processor can also be used to obtain the first echo signal of the first detection signal transmitted by the first transmitting antenna and the second detection signal transmitted by n second transmitting antennas. The second echo signal: detect pedestrians according to the first echo signal and the second echo signal, so that while using a single antenna to detect pedestrians, the position of the potential target can be detected in combination with n second transmitting antennas, so as to improve The angle measurement performance of the radar system, in turn, can improve the accuracy of pedestrian detection.

With reference to the first aspect, in some implementation manners of the first aspect, the processor is further configured to determine the position of the potential target according to the second echo signal; identify whether the potential target is pedestrian.

With reference to the first aspect, in some implementation manners of the first aspect, the processor is further configured to determine the position of the potential target according to the first echo signal and the second echo signal; The signal identifies whether the potential target is a pedestrian.

In the radar system provided by the embodiment of the present application, the processor may be used to combine the first echo signal and the second echo signal to determine the position of the potential target; identify the potential target according to the first echo signal Whether it is a pedestrian, so as to avoid the loss of resolution caused by a transmitting antenna in the radar system being only used to identify pedestrians, improve the angle measurement performance of the radar system, and thus improve the accuracy of pedestrian detection.

It should also be understood that, before identifying pedestrians according to the first echo signal, the present application first determines whether there is a potential target according to the first echo signal and the second echo signal, and determines the position of the potential target, and then Identify potential targets at different positions based on the first echo signal to determine whether they are pedestrians, avoiding pedestrian identification and analysis for all echo signals, thus reducing the start-up frequency of pedestrian micro-Doppler identification and greatly improving The efficiency of pedestrian detection is improved, and the power consumption of system operation is also reduced.

With reference to the first aspect, in some implementation manners of the first aspect, the processor is further configured to perform fast time processing on the first echo signal and the second echo signal respectively; The fast time processing results of the signal and the second echo signal are respectively stored in the first cube space and the second cube space; slow time processing is performed on the first cube space and the second cube space to obtain the position of the potential target.

It should be understood that fast time processing includes windowing and a Rang fast fourier transform (Rang FFT).

It should be understood that the slow time processing includes Doppler Fourier transform (Doppler FFT) on the cube space, multi-channel combination, constant false alarm rate detection (constant false alarm rate detection, CFAR), speed measurement and angle measurement and tracking, and then according to the speed / radar cross section (radar cross section, RCS) and other information to determine whether it is a potential target, and obtain the position information of the potential target.

With reference to the first aspect, in some implementation manners of the first aspect, in performing slow-time processing on the first cubic space and the second cubic space, the processor is further configured to thin out more than one in the first cubic space The Puller unit is accumulated to the corresponding position in the second cube space for multi-channel merging.

In slow time processing, multi-channel merging is usually involved. Since the lengths of the Doppler dimensions of the first cubic space and the second cubic space in the embodiment of the present application may be different, the present application needs to analyze this Heterogeneous cubic spaces are merged. Specifically, the processor in this application can achieve multi-channel merging by thinning out the Doppler unit in the first cubic space and accumulating to the corresponding position in the second cubic space, so that when determining the position information of the potential target, it can At the same time, the information in the first cube space and the second cube space can be used, so that the signal-to-noise ratio (SNR) benefit of multi-channel combination can be obtained and the angle measurement performance can be guaranteed.

With reference to the first aspect, in some implementations of the first aspect, it is characterized in that the first transmitting antenna is a single physical antenna or a single virtual antenna, and the single virtual antenna modulates the BPM or beam through a bi-phase code The shaping BF is virtually formed by encoding multiple physical antennas; each of the n second transmitting antennas is a single physical antenna or a single virtual antenna.

Optionally, the first transmitting antenna may be a single physical antenna, or may be a single virtual antenna. Among them, the single virtual antenna is virtually formed by encoding multiple physical antennas through bi-phase code modulation BPM or beamforming BF, which can increase the power of the first detection signal, thereby improving the recognition effect of pedestrians, and further improving pedestrian detection. accuracy.

Likewise, each of the n second transmitting antennas may be a single physical antenna, or may be a single virtual antenna. If there is a virtual antenna in the n second transmitting antennas, the power of the second detection signal can also be increased, thereby improving the accuracy of determining the position of the potential target, and further improving the accuracy of pedestrian detection.

With reference to the first aspect, in some implementation manners of the first aspect, if n≥2, the processor is further configured to control at least two of the n second transmit antennas to use frequency division multiplexing in one transmit period transmitted in a time-division multiplexed manner.

In a second aspect, a method for detecting pedestrians is provided, including: obtaining a first echo signal of a first detection signal transmitted by a first transmitting antenna and a second echo signal of a second detection signal transmitted by n second transmitting antennas. Echo signals, wherein the first transmitting antenna is used to identify pedestrians, the n second transmitting antennas are used to determine the position of potential targets, and the first transmitting antenna and the n second transmitting antennas are time-division multiplexed Intermittently transmit detection signals, the duty cycle of the first detection signal within a transmission cycle is located at [1/(n+1), 1/2], n is a positive integer; according to the first echo signal and the first Two echo signals detect pedestrians.

Optionally, before acquiring a first echo signal of a first detection signal transmitted by a first transmitting antenna and a second echo signal of a second detection signal transmitted by n second transmitting antennas, the method may further include : controlling one first transmitting antenna to transmit the first detection signal and n second transmitting antennas to transmit the second detection signal. Then it should be understood that the method may also include: controlling the first transmit antenna and the n second transmit antennas to interleave transmit probe signals in a time-division multiplexing manner, and during the process of transmitting probe signals, the first The duty ratio of the detection signal in a transmission period is controlled within [1/(n+1),1/2].

In the embodiment of the present application, on the one hand, the echo signals of the detection signals transmitted by one first transmitting antenna and n second transmitting antennas can be obtained, wherein the first transmitting antenna is used to identify pedestrians, and the n second transmitting antennas The antenna is used to determine the position of the potential target, and the first transmitting antenna and the n second transmitting antennas are interleavedly transmitted detection signals in a time-division multiplexing manner, and then based on the feedback from the first transmitting antenna and the n second transmitting antennas Wave signals are used to detect pedestrians, so that while using a single antenna to detect pedestrians, combined with n second transmitting antennas to detect the position of potential targets, so as to improve the performance of angle measurement for detection targets, and thus improve the accuracy of pedestrian detection sex. On the other hand, in the present application, the duty cycle of the first detection signal transmitted by the first transmitting antenna within a transmission period is in the interval [1/(n+1), 1/2], which can ensure the time for pedestrians to recognize the detection signal window, so as to ensure high-resolution sampling of micro-Doppler characteristics, improve the detection ability of micro-Doppler effect, improve and enhance the recognition rate of pedestrians, and finally improve the accuracy of pedestrian detection.

With reference to the second aspect, in some implementation manners of the second aspect, the duty cycle of the first detection signal within one transmission period is adjustable within [1/(n+1), 1/2].

With reference to the second aspect, in some implementations of the second aspect, the detecting pedestrians according to the first echo signal and the second echo signal includes: determining the position of the potential target according to the second echo signal; The first echo signal identifies whether the potential target is a pedestrian.

With reference to the second aspect, in some implementation manners of the second aspect, the detecting the pedestrian according to the first echo signal and the second echo signal includes: determining according to the first echo signal and the second echo signal The position of the potential target; identifying whether the potential target is a pedestrian according to the first echo signal.

With reference to the second aspect, in some implementation manners of the second aspect, the determining the position of the potential target according to the first echo signal and the second echo signal includes: the first echo signal and the second echo signal The echo signals are respectively subjected to fast time processing; the fast time processing results of the first echo signal and the second echo signal are respectively stored in the first cube space and the second cube space; The second cube space performs slow time processing to obtain the position of the potential target.

With reference to the second aspect, in some implementations of the second aspect, the slow time processing of the first cubic space and the second cubic space includes: thinning out the Doppler unit in the first cubic space and adding to the second The corresponding positions in the cube space are multi-channel merged.

With reference to the second aspect, in some implementations of the second aspect, the first transmit antenna is a single physical antenna or a single virtual antenna, and the single virtual antenna uses bi-phase code modulation BPM or beamforming BF to combine multiple The n physical antennas are encoded and virtually formed; each of the n second transmitting antennas is a single physical antenna or a single virtual antenna.

With reference to the second aspect, in some implementations of the second aspect, if n≥2, at least two of the n second transmit antennas use frequency division multiplexing or time division multiplexing within one transmission period emission.

With reference to the second aspect, in some implementation manners of the second aspect, the n second transmit antennas are located in a multiple-input multiple-output MIMO system.

In a third aspect, there is provided a device for detecting pedestrians, including a processor and a memory, the processor is coupled to the memory, the memory is used to store computer programs or instructions, and the processor is used to execute the The computer program or instruction of the second aspect makes the second aspect or the method in any possible implementation manner of the second aspect be executed.

In a fourth aspect, a radar is provided, including a receiver and a processor, the receiver is used for receiving echo signals, and the processor is used for performing any of the following tasks in the second aspect or the second aspect according to the echo signals. A method in one possible implementation.

In a fifth aspect, a vehicle is provided, including the radar system in the first aspect or any possible implementation manner of the first aspect, or including the device in the third aspect, or including the radar in the fourth aspect.

According to the sixth aspect, a computer program product is provided, including: a computer program (also referred to as code, or an instruction), which, when the computer program is executed, causes the computer to execute any of the above-mentioned second aspect and the second aspect. method in the implementation.

In a seventh aspect, a computer-readable storage medium is provided, storing a computer program or instruction, and the computer program or instruction is used to implement the second aspect and the method in any possible implementation manner of the second aspect.

In a ninth aspect, a computing device is provided, including: a communication interface; a memory for storing a computer program, and a processor for calling the computer program from the memory, and when the computer program is executed, the computing device performs such as executing the second A method in any possible implementation of the aspect or the second aspect.

In a tenth aspect, a chip is provided, and a processing system is provided on the chip, and the processing system is configured to execute instructions of the method in the second aspect or any possible implementation manner of the second aspect.

Description of drawings

Fig. 1 is a structural example diagram of a radar provided in an embodiment of the present application.

Fig. 2 is an example diagram of a radar system provided by an embodiment of the present application.

Fig. 3 is an example diagram of a transmission waveform provided by an embodiment of the present application.

Fig. 4 is an example diagram of another transmission waveform provided by the embodiment of the present application.

Fig. 5 is an example diagram of another transmission waveform provided by the embodiment of the present application.

Fig. 6 is an example diagram of another transmission waveform provided by the embodiment of the present application.

Fig. 7 is an example diagram of a heterogeneous cubic space provided by an embodiment of the present application.

FIG. 8 is an example diagram of spatial merging of heterogeneous cubes provided by an embodiment of the present application.

FIG. 9 is an example diagram of a pedestrian detection process provided by an embodiment of the present application.

FIG. 10 is an example diagram of another radar system provided by an embodiment of the present application.

Fig. 11 is an example diagram of another radar system provided by an embodiment of the present application.

Fig. 12 is an example diagram of a method for detecting pedestrians provided by an embodiment of the present application.

Fig. 13 is an exemplary block diagram of a hardware structure of an apparatus provided by an embodiment of the present application.

Detailed ways

In order to facilitate the understanding of the technical solutions of the embodiments of the present application, several terms involved in the present application are firstly introduced.

Millimeter wave radar: It is a radar that works in the millimeter wave band. Usually millimeter wave refers to the 30-300GHz frequency domain (wavelength 1-10mm). The wavelength of millimeter wave is between microwave and centimeter wave, so millimeter wave radar has some advantages of microwave radar and photoelectric radar.

The micro-Doppler effect of pedestrians: The micro-Doppler effect refers to the micro-motion (vibration, rotation, rollover, precession, nutation, etc.) of the moving target in addition to the movement of the main body. This kind of micro-motion causes additional Doppler frequency modulation on the radar echo signal, and produces frequency conversion near the Doppler shift frequency of the transmitted signal generated by the movement of the main body, which broadens the Doppler spectrum of the target. The micro-Doppler information contained in the radar target echo can finely describe the shape, structure, scattering characteristics and unique fine motion characteristics of the target, and further reflect the type and motion intention of the target. The human body is a typical cooperative system composed of many rigid body parts, and each rigid body part coordinates the movement through the joint torque. Micro-Doppler information generated by different limb movements can be used to distinguish human bodies from other objects.

Multiple-in multiple-out (MIMO): refers to the use of multiple transmitting antennas and receiving antennas at the transmitting end and the receiving end, respectively, so that signals are transmitted and received through multiple antennas at the transmitting end and the receiving end, thereby improving communication quality .

Time-division multiplexing (TDM): different signals are interleaved in different time periods and transmitted along the same channel; at the receiving end, a method is used to combine the signals in each time period Communication technology that extracts and restores the original signal.

Signal-to-noise ratio (SNR): The ratio of the useful signal amplitude to the noise amplitude at a given time point, the larger the value, the better.

Echo data (ADC data): The working principle of the radar is that the radar emits electromagnetic waves to irradiate the target and receives its echo. The echo data is the corresponding data of the echo. According to the echo data, the target to the electromagnetic wave emission can be obtained. Point distance, distance change rate (radial velocity), azimuth, height and other information.

Constant false alarm rate detection (constant false alarm rate detection, CFAR): It refers to the technology that the radar system distinguishes the signal and noise output by the receiving end to determine whether the target signal exists under the condition of keeping the false alarm probability constant.

Direction of arrival (DOA): refers to the direction of arrival of space signals.

fast fourier transform (FFT): A mathematical formula that relates a signal sampled in time or space to the same signal sampled in frequency. In signal processing, the Fourier transform can reveal important features of a signal (i.e. its frequency components). The range-dimensional Fourier transform in this application may be abbreviated as Range-FFT; the Doppler-dimensional Fourier transform may be abbreviated as Doppler-FFT.

Range-Doppler map (range-doppler map, RD map): In RD map, R stands for distance (unit: m), and sometimes it can be expressed by echo delay time (unit: s). D represents the Doppler frequency, which can be used to indicate the speed of the target, or indirectly measure the target azimuth.

Radar signal processing unit (radar signal process unit, RSPU): used to process radar signals.

Beamforming (BF): It is a technology that transmits or receives signals in an energy-concentrated and directional manner, which can comprehensively improve the signal quality of transmission and reception. In a multi-antenna system, if there are two beams with equal attenuation when the signals transmitted by different antennas arrive at a certain position, and the phases of the two beams are opposite, spatial holes may appear. The beamforming technology can pre-compensate the phase of the transmitting antenna, so that two or more beams can be superimposed to achieve the best effect.

Binary phase modulation (BPM): It is used to virtualize multiple physical antennas into one antenna through encoding.

Fast time (fast time) and slow time (slow time): When the radar is working, the pulse signal is sent periodically, and the echo signal is sampled within the pulse interval time. Although the echo sampling interval and the pulse repetition interval (pulse period) are within a On the time axis, but the difference in magnitude is very large, the echo sampling interval is about 10 ^-8 level, and the pulse repetition period is about 10 ^-3 level, so it may be inconvenient to process. Therefore, the echo sampling interval and the pulse repetition period are divided into two dimensions, which are called fast time and slow time respectively.

Radar cross section (radar cross section, RCS): refers to the ratio of the return scattered power to the power density of the target truncation within a unit solid angle in the direction of incidence of the radar.

Chirp: It is a term in communication technology related to coded pulse technology, which means that when the pulse is coded, its carrier frequency increases linearly during the pulse duration (that is, the frequency changes (increases or decreases) with time signal), when the pulse is changed to the audio ground, it will emit a sound that sounds like the chirping of a bird, hence the name "chirp".

Duty cycle: refers to the ratio of the power-on time to the total time in a pulse cycle.

The technical solutions in this application will be described in detail below in conjunction with the accompanying drawings.

Fig. 1 is a structural example diagram of a radar 100 provided in an embodiment of the present application. It should be understood that the radar in this embodiment of the present application is mainly a millimeter wave radar. As shown in FIG. 1 , the radar 100 includes a transmitting end 120 , a receiving end 130 and a processing unit 110 . Optionally, the processing unit 110 may include a central processing unit (central processor unit, CPU), FPGA or ASIC, or may also be other types of processing chips. During the pedestrian detection process of the radar, the transmitting end 120 sends a transmitting signal to the target object, and the transmitting signal is a pulse signal. The target object reflects the transmitted signal, and the receiving end 130 receives the echo signal reflected by the target object. In the embodiment of the present application, the transmit signal may also be referred to as transmit signal waveform, transmit pulse, transmit pulse signal, or detection signal, etc., and the echo signal may also be referred to as echo signal waveform, receive pulse, or receive pulse signal, etc. In this application, the processing unit 110 is mainly used to process the echo signal to detect pedestrians; optionally, the processing unit 110 can also be used to control the transmitting end 120 to transmit signals, which is not limited.

In order to solve the above problems, an embodiment of the present application provides a radar system, which can detect the position of a potential target in combination with n second transmitting antennas while using a single antenna to detect pedestrians, so as to improve the radar system. The angular measurement performance can improve the accuracy of pedestrian detection.

It should be understood that the embodiments of the present application can be widely applied in various fields, for example, artificial intelligence field, unmanned driving system, automatic driving system, augmented reality (augmented reality, AR) technology, virtual reality (virtual reality, VR) technology wait. Among them, automatic driving is a mainstream application in the field of artificial intelligence. The automatic driving technology relies on the cooperation of computer vision, radar, monitoring devices and global positioning systems, so that motor vehicles can realize automatic driving without human active operation.

Fig. 2 is an example diagram of a radar system provided by an embodiment of the present application. As shown in FIG. 2 , the radar system 200 includes an antenna system 210 and a processor 220 . Wherein, the antenna system 210 is equivalent to the transmitter 120 in the radar 100 and is mainly used for transmitting detection signals; the processor 220 is equivalent to the processing unit 110 in the radar 100 and is mainly used for pedestrian detection. The radar system 200 is described in detail below.

The antenna system 210 in the radar system 200 includes a first transmitting antenna and n second transmitting antennas, wherein the first transmitting antenna is mainly used to identify pedestrians, and the n second transmitting antennas are mainly used to determine the position of potential targets .

The processor 220 in the radar system 200 is coupled to the antenna system 210, and is used to control the first transmitting antenna and the n second transmitting antennas to interleavely transmit detection signals in a time-division multiplexing manner, wherein the first transmitting antenna transmitted by the first transmitting antenna The duty cycle of a detection signal within a transmission cycle is in [1/(n+1), 1/2], where n is a positive integer.

It should be understood that the duty ratio of the first detection signal transmitted by the first transmitting antenna within one transmitting period may be any value in the interval [1/(n+1), 1/2]. Exemplarily, if n is equal to 1, the duty ratio of the first detection signal in one transmission period may be 1/2; if n is equal to 2, the duty ratio of the first detection signal in one transmission period may be in the interval [ 1/3,1/2]; if n is greater than or equal to 3, the duty cycle of the first detection signal in one transmission period can be in the interval [1/(n+1),1/2] any value in . It should also be understood that the greater the duty cycle of the first detection signal in one transmission cycle, the more the time window for the pedestrian identification detection signal can be ensured, thereby ensuring high-resolution sampling of the micro-Doppler characteristics and improving the micro-Doppler The ability to detect the Le effect, improve and enhance the recognition rate of pedestrians, and ultimately improve the accuracy of pedestrian detection. As a preferred solution, if n is greater than or equal to 3, the duty ratio of the first detection signal in one transmission period can be any value in the interval [1/3, 1/2]. And for the convenience of description, in the following embodiments, the duty ratio of the first detection signal in one transmission period may be 1/2 as an example for description, see examples 1 to 4 below.

It should be understood that after the duty cycle of the first detection signal in one transmission period is confirmed, the second detection signal may occupy the remaining transmission time. For example, when the duty ratio of the first detection signal in one transmission period is 1/2, the duty ratio of the second detection signal in one transmission period may be the remaining 1/2.

The radar system provided by the embodiment of the present application can detect the position of potential targets by combining n second transmitting antennas while using a single antenna to detect pedestrians, so as to improve the angle measurement performance of the radar system, thereby improving the detection of pedestrians. accuracy.

Optionally, while the first transmitting antenna in this application is used to identify pedestrians, it can also work with n second transmitting antennas to determine the position of a potential target, so as to further improve the angle measurement performance of the antenna DOA in the radar system.

Optionally, the antenna system 210 may further include: a controller, configured to adjust a duty cycle of the first detection signal within one transmission period.

The antenna system of the radar system provided in the embodiment of the present application can also include a controller, which can be used to adjust the duty cycle of the first detection signal in one transmission period, so that in actual operation, the The duty cycle of the first detection signal can be flexibly adjusted, so that the wideness of application scenarios of the radar system can be improved. For example, in a scene with higher requirements for identifying pedestrians, the duty cycle of the first detection signal can be appropriately increased; in a scene with higher requirements for angle measurement performance, the duty cycle of the first detection signal can be appropriately reduced Compare.

Optionally, if n≥2, the processor 220 may also be configured to control at least two of the n second transmit antennas to use frequency division multiplexing (see example 2 below) or time division multiplexing within one transmission cycle Emitted with the method (see Example 1 and Example 3 below).

The waveform of the transmitted detection signal (hereinafter referred to as the transmission waveform) will be described below in conjunction with Examples 1 to 4 by taking the duty cycle of the first detection signal as 1/2 in one transmission period as an example. It should be understood that the following examples 1 to 4 are just examples, and in actual operation, there may also be other forms, as long as the duty cycle of the first detection signal meets the above-mentioned interval, and the first detection signal and the second detection signal It can be transmitted in an interleaved manner.

Example 1:

FIG. 3 is an example diagram of a transmission waveform provided by an embodiment of the present application. As shown in Figure 3, in this waveform, TX0 (i.e. the first transmitting antenna) is a high-frequency repetitive transmission, and the chirp number (i.e. the first detection signal) transmitted by it has a duty ratio of 1/ 2. TX1 to TX7 (that is, the second transmitting antenna) evenly allocate the remaining transmitting time, and stagger transmitting in the manner shown in FIG. 3 . Among them, TX0 is the transmitting antenna required for pedestrian identification, TX1 to TX7 are the transmitting antennas required for scene detection (including whether there is a potential target and the detection of the potential target position), and the waveform duty cycle for identifying pedestrians is 1/2, It can improve the detection ability of the micro-Doppler effect of pedestrians, thereby improving the recognition rate of pedestrians.

In addition, FIG. 3 also shows the RD map corresponding to the first transmitting antenna and the second transmitting antenna, that is, the RD cube space map. For Example 1, the R dimension (ie, distance dimension) of the first transmitting antenna and the second transmitting antenna are the same, and the D dimension (ie, Doppler dimension) of the first transmitting antenna is 7 times that of the second transmitting antenna. As an example, the size of cube1 of the first transmitting antenna is 1024*448, wherein, 1024 is the length of R dimension, and 448 is the length of D dimension; each transmitting antenna in the second transmitting antenna (that is, any of TX1 to TX7 A) The size of cube2 is 1024*64, where 1024 is the length of the R dimension, and 64 is the length of the D dimension.

Example 2:

Fig. 4 is an example diagram of another transmission waveform provided by the embodiment of the present application. As shown in Figure 4, in this waveform, the duty cycle of the chirp number (ie, the first detection signal) transmitted by TX0 (ie, the first transmitting antenna) in one transmission cycle is 1/2, and TX1 to TX3 account for the remaining 1/2 and TX1~TX3 are transmitted by frequency division multiplexing. Among them, TX0 and TX1~TX3 transmit interleavedly, TX0 is the transmitting antenna required for pedestrian recognition, TX1~TX3 are the transmitting antennas required for scene detection, and the waveform duty ratio of identifying pedestrians is 1/2, which can improve the micro The detection ability of the Doppler effect, thereby improving the recognition rate of pedestrians.

In addition, FIG. 4 also shows the RD map corresponding to the first transmitting antenna and the second transmitting antenna. For Example 2, the R dimension (ie, distance dimension) of the first transmitting antenna and the second transmitting antenna are the same, and the D dimension (ie, Doppler dimension) of the first transmitting antenna is three times that of the second transmitting antenna. As an example, the size of cube1 of the first transmitting antenna is 1024*512, wherein, 1024 is the length of R dimension, and 512 is the length of D dimension; each transmitting antenna in the second transmitting antenna (that is, any of TX1 to TX3 A) The size of cube2 is 1024*(512/3), where 1024 is the length of the R dimension, and 512/3 is the length of the D dimension.

Example 3:

Fig. 5 is an example diagram of another transmission waveform provided by the embodiment of the present application. As shown in Figure 5, in this waveform, the duty cycle of the chirp number (ie, the first probe signal) transmitted by the TX0/1 virtual antenna (ie, the first transmit antenna) in one transmit cycle is 1/2, and TX2 /3, TX4/5 and TX6/7 (that is, the second transmit antenna) distribute the remaining transmit time equally, and stagger transmit in the manner shown in FIG. 5 . Among them, TX0/1, TX2/3, TX4/5, and TX6/7 are respectively an antenna virtually formed by encoding physical antennas TX0 and TX1, TX2 and TX3, TX4 and TX5, TX6 and TX7 through BPM encoding. Among them, TX0/1 is the transmitting antenna required for pedestrian recognition, TX2/3, TX4/5 and TX6/7 are the transmitting antennas required for scene detection, and the waveform duty cycle of pedestrian recognition is 1/2, which can improve The ability to detect the micro-Doppler effect of pedestrians, thereby improving the recognition rate of pedestrians.

In addition, FIG. 5 also shows the RD map corresponding to the first transmitting antenna and the second transmitting antenna. For Example 3, the R dimension (ie, distance dimension) of the first transmitting antenna and the second transmitting antenna are the same, and the D dimension (ie, Doppler dimension) of the first transmitting antenna is three times that of the second transmitting antenna. As an example, the size of the cube1 of the first transmitting antenna is 1024*384, wherein, 1024 is the length of the R dimension, and 384 is the length of the D dimension; each transmitting antenna (ie TX2/3, TX4/ 5 and TX6/7), the size of cube2 is 1024*128, where 1024 is the length of the R dimension, and 128 is the length of the D dimension.

Example 4:

Fig. 6 is an example diagram of another transmission waveform provided by the embodiment of the present application. As shown in Figure 6, in this waveform, the duty cycle of the chirp number (that is, the first detection signal) transmitted by the VTX0 BF virtual antenna (that is, the first transmitting antenna) in one transmission cycle is 1/2, and the VTX1 BF The duty cycle of the detection signal of the virtual antenna (that is, the second transmitting antenna) is the remaining 1/2, and the VTX0 BF and VTX1 BF are staggered to transmit in the manner shown in Figure 6. Among them, VTX0 BF and VTX1 BF are respectively an antenna formed by virtualizing physical antennas TX0 and TX1, TX2 and TX3 through BF. Among them, VTX0BF is the transmitting antenna required for pedestrian recognition, and the waveform duty ratio of pedestrian recognition is 1/2, which improves the detection ability of the micro-Doppler effect of pedestrians, thereby improving the recognition rate of pedestrians.

In addition, FIG. 6 also shows the RD map corresponding to the first transmitting antenna and the second transmitting antenna. For Example 4, the R dimension (ie, the distance dimension) and the D dimension (ie, the Doppler dimension) of the first transmitting antenna and the second transmitting antenna are the same in size. As an example, the size of cube1 of the first transmitting antenna and the size of cube2 of the second transmitting antenna are both 1024*512, where 1024 is the length of the R dimension, and 512 is the length of the D dimension.

It should also be understood that, in the above example, although the slope of the first detection signal waveform is consistent with the second detection signal waveform, in practice, the slope of the first detection signal waveform may also be inconsistent with the slope of the second detection signal waveform, This application does not limit this.

Optionally, the processor 220 may also be configured to acquire a first echo signal of a first detection signal transmitted by a first transmitting antenna and a second echo signal of a second detection signal transmitted by n second transmitting antennas; according to The first echo signal and the second echo signal detect pedestrians. Therefore, while a single antenna is used to detect pedestrians, the position of potential targets can be detected in combination with n second transmitting antennas, so as to improve the angle measurement performance of the radar system, thereby improving the accuracy of pedestrian detection.

Optionally, the processor 220 may also be configured to determine the position of the potential target according to the second echo signal; and identify whether the potential target is a pedestrian according to the first echo signal.

It should be understood that the identification of pedestrians based on the echo signal of the first transmitted wave mainly uses the micro-Doppler characteristics of pedestrians in the echo signal of the first transmitted wave to identify pedestrians. For the specific identification process, please refer to the fine processing process in method 900 below. .

Optionally, the processor 220 may also be configured to determine the position of the potential target according to the first echo signal and the second echo signal; and identify whether the potential target is a pedestrian according to the first echo signal.

In the radar system provided in the embodiment of the present application, the processor may be used to determine the position of the potential target in combination with the first echo signal and the second echo signal; identify whether the potential target is a pedestrian according to the first echo signal, Therefore, it is possible to avoid the loss of resolution caused by a transmitting antenna in the radar system being only used to identify pedestrians, improve the angle measurement performance of the radar system, and thus improve the accuracy of pedestrian detection.

Optionally, the processor 220 may also be configured to respectively perform fast time processing on the first echo signal and the second echo signal; respectively store the fast time processing results on the first echo signal and the second echo signal In the first cube space and the second cube space; performing slow time processing on the first cube space and the second cube space to obtain the position of the potential target.

It should be understood that fast time processing includes windowing and Range Fourier Transform Rang FFT.

It should be understood that the slow time processing includes Doppler Fourier transform Doppler FFT, multi-channel merging, CFAR, speed measurement and angle measurement and tracking on the cube space, and then determine whether it is a potential target based on the speed/RCS and other information, and obtain the potential target location information.

Optionally, in the slow time processing of the first cube space and the second cube space, the processor 220 may also be used to thin out the Doppler units accumulated in the first cube space and accumulated in the second cube space Multi-channel merging is performed at the corresponding position.

In slow time processing, multi-channel merging is usually involved. Since the lengths of the Doppler dimensions of the first cubic space and the second cubic space in the embodiment of the present application may be different, the present application needs to analyze this Heterogeneous cubic spaces are merged. Specifically, the processor in this application can achieve multi-channel merging by thinning out the Doppler unit in the first cubic space and accumulating to the corresponding position in the second cubic space, so that when determining the position information of the potential target, it can At the same time, the information in the first cube space and the second cube space can be used, so that the SNR benefit of multi-channel merging can be obtained and the angle measurement performance can be guaranteed.

The mechanism of merging heterogeneous cube spaces will be introduced below with reference to FIG. 7 and FIG. 8 . Among them, heterogeneous means that the dimensions of the two cubic spaces are not the same.

As shown in FIG. 7 , cube1 is the cubic space of the first transmitting antenna, and cube2 is the cubic space of the second transmitting antenna. The R dimensions of the two cubic spaces have the same size, and the length of the D dimension is proportional to the duty cycle.

When doing multi-channel accumulation, the Doppler bin in cube1 is extracted at intervals and accumulated to the corresponding Doppler position in cube2, so as to increase the number of virtual channels in the angle dimension and improve the angle measurement resolution.

It should be understood that the present application does not limit the manner of determining the sampling interval. Optionally, in actual operation, the extraction interval may be determined according to system parameters (eg, D-dimensional frequency domain parameters).

As an example, FIG. 8 is an example diagram of spatial merging of heterogeneous cubes provided by an embodiment of the present application. It should be understood that Fig. 8 is only used as an example, and does not constitute a limitation to the present application. As shown in Fig. 8, in this example, the sampling interval is 3 Doppler units. Specifically, for cube1, one Doppler unit is extracted every three Doppler units and accumulated to the corresponding Doppler unit position in cube2 (for example, D0 in cube1 can be extracted and accumulated in D0 in cube2 position, extract D4 in cube1 and add it to D1 position in cube2, extract D8 in cube1 and add it to D2 position in cube2) to realize the space merging of heterogeneous cubes.

FIG. 9 is an example diagram of a pedestrian detection process provided by an embodiment of the present application. As shown in FIG. 9, the pedestrian detection process 900 includes the following steps:

S910, Transmit a detection signal.

The radar transmits the detection signal, that is, the first transmission antenna transmits the first detection signal and the n second transmission antennas transmits the second detection signal. For the definition of the detection signal transmission, please refer to the above description.

S920. Receive the echo and process the echo.

The echo processing includes rough processing and fine processing, and the processing process will be introduced below.

(1) Rough processing (that is, first-level processing):

a) Fast time processing:

Perform fast-time chirp processing (including windowing and Range FFT) on the echo data of the first detection signal and the second detection signal, and then store the processing results in the cube1 space and cube2 space of the cube storage space respectively.

b) Slow time processing:

Perform Doppler-FFT, multi-channel merging, CFAR, speed measurement and angle measurement and tracking on cube1 space and cube2 space, and then determine whether it is a potential target (that is, a potential pedestrian target) based on information such as speed/RCS, and obtain the distance information of the potential target (i.e. location information).

(2) Fine processing (that is, second-level processing, that is, micro-Doppler accurate identification):

The process of accurately identifying pedestrians with micro-Doppler is as follows: According to the distance of the potential target, the range unit (Rangbin) data of interest is obtained, and one or several selected Rangbin data (ie, the target Rangbin) are preprocessed (interpolation/ extrapolation), and then perform time-frequency analysis (such as short time Fourier transform (STFT)), parameter estimation, human/vehicle classification, and output pedestrian/vehicle results, so that potential targets can be identified Whether it is a pedestrian.

Optionally, at least one of processes such as time-frequency analysis, parameter estimation, and human/vehicle classification may also be directly implemented by a pre-trained model, without limitation.

In the embodiment of the present application, through coarse/fine secondary processing, pedestrian identification analysis is avoided for all echo signals, the start-up frequency of micro-Doppler accurate identification is relatively reduced, and the efficiency of pedestrian identification is greatly improved. It also reduces system operating power consumption.

FIG. 10 and FIG. 11 are diagrams illustrating examples of radar systems provided by embodiments of the present application. It should be understood that the difference between Figures 10 and 11 lies in the different forms and numbers of transmitting antennas. It should be understood that the transmitting antennas shown in FIGS. 10 and 11 are only examples, and do not limit the present application. In addition, the embodiment of the present application does not limit the number of receiving antennas.

As shown in FIG. 10 , in this example, a radar system 1000 includes a monolithic microwave integrated circuit (MMIC), an RSPU, and transmitting antennas TX0 to TX3.

Among them, the echo signals of the detection signals transmitted by the transmitting antenna TX0 (equivalent to the first transmitting antenna) are used to identify pedestrians, and the echo signals of the detection signals transmitted by the transmitting antennas TX1 to TX3 (equivalent to the second transmitting antenna) are mainly used for identification. For the detection of potential target positions, the MMIC (equivalent to a processor) is used to complete the circuit processing of the transmitted waveform, and the RSPU (equivalent to a processor) is used to process the received echo signal to detect pedestrians.

As shown in FIG. 11 , in this example, a system architecture 1100 includes an MMIC, an RSPU, and transmit antennas TX0/1, TX2/3, TX4/5, and TX6/7. Among them, TX0/1, TX2/3, TX4/5, and TX6/7 are the virtual antennas formed by encoding the physical antennas TX0 and TX1, TX2 and TX3, TX4 and TX5, TX6 and TX7 respectively through BPM and other technologies.

Among them, the echo signal of the detection signal transmitted by the transmitting antenna TX0/1 (equivalent to the first transmitting antenna) is used to identify pedestrians, and the transmitting antennas TX2/3, TX4/5 and TX6/7 (equivalent to the second transmitting antenna) transmit The echo signal of the detection signal is mainly used for the detection of the potential target position, the MMIC (equivalent to a processor) is used to complete the circuit processing of the transmitted waveform, and the RSPU (equivalent to a processor) is used to process the received echo signal to detect pedestrians.

It should also be understood that the number of transmitting antennas connected to each MMIC in FIGS. 10 and 11 is only an example, which is not limited in the present application.

Fig. 12 is an example diagram of a method for detecting pedestrians provided by an embodiment of the present application. It should be understood that the method 1200 may be applied to the above-mentioned radar 100 , and may also be applied to the above-mentioned radar system 200 , which is not limited in this application. As shown in Fig. 12, the method 1200 includes step S1210 and step S1220.

S1210. Acquire a first echo signal of a first detection signal transmitted by one first transmitting antenna and a second echo signal of a second detection signal transmitted by n second transmitting antennas.

Among them, the first transmitting antenna is used to identify pedestrians, and the n second transmitting antennas are used to determine the position of potential targets. The duty cycle of the detection signal within one transmission cycle is in [1/(n+1), 1/2], where n is a positive integer.

Optionally, before obtaining the first echo signal of the first detection signal transmitted by one first transmitting antenna and the second echo signal of the second detection signal transmitted by n second transmitting antennas, the method 1200 may further include : controlling one first transmitting antenna to transmit the first detection signal and n second transmitting antennas to transmit the second detection signal. Then it should be understood that the method may also include: controlling the first transmit antenna and the n second transmit antennas to interleave transmit probe signals in a time-division multiplexing manner, and during the process of transmitting probe signals, the first The duty ratio of the detection signal in a transmission period is controlled within [1/(n+1),1/2].

Optionally, the duty ratio of the first detection signal within one transmission period can be adjusted within [1/(n+1),1/2].

Optionally, the first transmitting antenna may be a single physical antenna, or may be a single virtual antenna.

Optionally, a single virtual antenna may be virtually formed by encoding multiple physical antennas through bi-phase code modulation BPM or beamforming BF.

Likewise, each of the n second transmit antennas may be a single physical antenna or a single virtual antenna.

Optionally, if n≧2, at least two of the n second transmitting antennas may transmit in a frequency division multiplexing manner or in a time division multiplexing manner within one transmission period.

Optionally, the n second transmit antennas may be located in a multiple-input multiple-output MIMO system.

S1220. Detect pedestrians according to the first echo signal and the second echo signal.

Optionally, the position of the potential target may be determined first according to the second echo signal; and then whether the potential target is a pedestrian is identified according to the first echo signal.

Optionally, the position of the potential target may also be firstly determined according to the first echo signal and the second echo signal; and then whether the potential target is a pedestrian is identified according to the first echo signal.

Optionally, determining the position of the potential target according to the first echo signal and the second echo signal may include: respectively performing fast time processing on the first echo signal and the second echo signal; The fast time processing results of the echo signal and the second echo signal are respectively stored in the first cube space and the second cube space; slow time processing is performed on the first cube space and the second cube space to obtain the position of the potential target.

Optionally, performing slow time processing on the first cube space and the second cube space may include: thinning out corresponding positions accumulated by the Doppler unit in the first cube space to the second cube space to perform multi-channel merging.

It should be understood that relevant descriptions in the radar system 200 are also applicable to this method embodiment, and details are not repeated here.

Fig. 13 is an exemplary block diagram of a hardware structure of an apparatus provided by an embodiment of the present application. Optionally, the apparatus 1300 may specifically be a computer device. The device 1300 includes a memory 1310 , a processor 1320 , a communication interface 1330 and a bus 1340 . Wherein, the memory 1310 , the processor 1320 , and the communication interface 1330 are connected to each other through the bus 1340 .

The memory 1310 may be a read only memory (read only memory, ROM), a static storage device, a dynamic storage device or a random access memory (random access memory, RAM). The memory 1310 may store a program. When the program stored in the memory 1310 is executed by the processor 1320, the processor 1320 is configured to execute various steps in the method for detecting pedestrians in the embodiment of the present application.

Processor 1320 may be a general-purpose central processing unit (central processing unit, CPU), a microprocessor, an application specific integrated circuit (application specific integrated circuit, ASIC), a graphics processing unit (graphics processing unit, GPU) or one or more The integrated circuit is used to execute related programs to implement the method for detecting pedestrians in the method embodiment of the present application.

The processor 1320 may also be an integrated circuit chip with signal processing capabilities. In the implementation process, the method for detecting pedestrians of the present application may be implemented by an integrated logic circuit of hardware in the processor 1320 or instructions in the form of software.

The above-mentioned processor 1320 can also be a general-purpose processor, a digital signal processor (digital signal processing, DSP), an application-specific integrated circuit (ASIC), a ready-made programmable gate array (field programmable gate array, FPGA) or other programmable logic devices, Discrete gate or transistor logic devices, discrete hardware components. Various methods, steps, and logic block diagrams disclosed in the embodiments of the present application may be implemented or executed. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module can be located in a mature storage medium in the field such as random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, register. The storage medium is located in the memory 1310, and the processor 1320 reads the information in the memory 1310, and combines its hardware to complete the functions required by the modules included in the device of the embodiment of the present application, or execute the method for detecting pedestrians in the method embodiment of the present application .

The communication interface 1330 implements communication between the apparatus 1300 and other devices or communication networks by using a transceiver device such as but not limited to a transceiver.

Bus 1340 may include a pathway for communicating information between various components of device 1300 (eg, memory 1310, processor 1320, communication interface 1330).

The embodiment of the present application also provides a vehicle, which includes the above-mentioned radar system 200 , or includes the above-mentioned device 1300 , or includes the above-mentioned radar 100 .

Alternatively, the vehicle may be a car, truck, motorcycle, bus, boat, airplane, helicopter, lawn mower, recreational vehicle, fairground vehicle, construction equipment, streetcar, golf cart, train, and cart etc., the embodiments of the present application are not specifically limited.

The embodiment of the present application also provides a computer program product, including: a computer program (also referred to as code, or an instruction), which, when the computer program is executed, causes the computer to execute the above-mentioned method 900 or method 1200.

The embodiment of the present application also provides a computer-readable storage medium, which stores a computer program or instruction, and the computer program or instruction is used to implement the above-mentioned method 900 or method 1200 .

The embodiment of the present application also provides a computing device, including: a communication interface; a memory for storing a computer program, and a processor for calling the computer program from the memory, and when the computer program is executed, the computing device executes the above method 900 or method 1200.

The embodiment of the present application also provides a chip, on which a processing system is arranged, and the processing system is used to execute the above-mentioned method 900 or method 1200 .

Those skilled in the art can appreciate that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present application.

Those skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process of the above-described system, device and unit can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or May be integrated into another system, or some features may be ignored, or not implemented. In another point, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, each unit may exist separately physically, or two or more units may be integrated into one unit.

If the functions described above are realized in the form of software function units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disc and other media that can store program codes. .

The above is only a specific implementation of the application, but the scope of protection of the application is not limited thereto. Anyone familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the application. Should be covered within the protection scope of this application. Therefore, the protection scope of the present application should be determined by the protection scope of the claims.

Claims

A radar system for detecting pedestrians, characterized in that it includes:

The antenna system includes a first transmitting antenna and n second transmitting antennas, wherein the first transmitting antenna is used to identify pedestrians, and the n second transmitting antennas are used to determine the position of a potential target;

A processor, coupled to the antenna system, configured to control the first transmit antenna and the n second transmit antennas to transmit detection signals interleavedly in a time-division multiplexing manner, wherein the first transmit antenna transmits The duty cycle of the first detection signal within one transmission cycle is in [1/(n+1), 1/2], where n is a positive integer.
The system of claim 1, wherein the antenna system further comprises:

a controller, configured to adjust the duty ratio of the first detection signal within one transmission cycle.
The system according to claim 1 or 2, wherein the processor is further configured to:

Acquiring a first echo signal of the first detection signal transmitted by the first transmitting antenna and a second echo signal of the second detection signal transmitted by the n second transmitting antennas;

A pedestrian is detected according to the first echo signal and the second echo signal.
The system of claim 3, wherein the processor is further configured to:

determining the position of the potential target based on the first echo signal and the second echo signal;

Identifying whether the potential target is a pedestrian according to the first echo signal.
The system of claim 4, wherein the processor is further configured to:

performing fast time processing on the first echo signal and the second echo signal respectively;

storing fast time processing results of the first echo signal and the second echo signal in a first cube space and a second cube space, respectively;

Slow time processing is performed on the first cube space and the second cube space to obtain the position of the potential target.
The system according to claim 5, wherein in the slow-time processing of the first cube space and the second cube space, the processor is further configured to:

The Doppler unit in the first cubic space is extracted at intervals and accumulated to the corresponding position in the second cubic space for multi-channel merging.
The system according to any one of claims 1 to 6, wherein the first transmitting antenna is a single physical antenna or a single virtual antenna, and the single virtual antenna is modulated by a bi-phase code BPM or The beamforming BF encodes and virtually forms multiple physical antennas; each of the n second transmitting antennas is a single physical antenna or a single virtual antenna.
The system according to any one of claims 1 to 7, wherein if n≥2, the processor is further configured to:

Controlling at least two of the n second transmitting antennas to transmit in a frequency division multiplexing manner or in a time division multiplexing manner within one transmission period.
The system according to any one of claims 1 to 8, wherein the n second transmit antennas are located in a multiple-input multiple-output (MIMO) system.
A method for detecting pedestrians, comprising:

Acquiring a first echo signal of a first detection signal transmitted by a first transmitting antenna and a second echo signal of a second detection signal transmitted by n second transmitting antennas, wherein the first transmitting antenna is used to identify For pedestrians, the n second transmitting antennas are used to determine the position of potential targets, the first transmitting antenna and the n second transmitting antennas transmit detection signals interleavedly in a time-division multiplexing manner, and the first detecting The duty cycle of the signal within a transmission period is [1/(n+1),1/2], n is a positive integer;

A pedestrian is detected according to the first echo signal and the second echo signal.
The method according to claim 10, characterized in that the duty cycle of the first detection signal in one transmission cycle is adjustable within [1/(n+1), 1/2].
The method according to claim 10 or 11, wherein the detecting pedestrians according to the first echo signal and the second echo signal comprises:

determining the position of the potential target based on the first echo signal and the second echo signal;

Identifying whether the potential target is a pedestrian according to the first echo signal.
The method according to claim 12, wherein the determining the position of the potential target according to the first echo signal and the second echo signal comprises:

performing fast time processing on the first echo signal and the second echo signal respectively;

storing fast time processing results of the first echo signal and the second echo signal in a first cube space and a second cube space, respectively;

Slow time processing is performed on the first cube space and the second cube space to obtain the position of the potential target.
The method according to claim 13, wherein said performing slow time processing on said first cube space and said second cube space comprises:

The Doppler unit in the first cubic space is extracted at intervals and accumulated to the corresponding position in the second cubic space for multi-channel merging.
The method according to any one of claims 10 to 14, wherein the first transmitting antenna is a single physical antenna or a single virtual antenna, and the single virtual antenna is modulated by a bi-phase code BPM or The beamforming BF encodes and virtually forms multiple physical antennas; each of the n second transmitting antennas is a single physical antenna or a single virtual antenna.
The method according to any one of claims 10 to 15, wherein, if n≥2, at least two of the n second transmitting antennas use frequency division multiplexing or Transmit in time-division multiplexing mode.
The method according to any one of claims 10 to 16, wherein the n second transmit antennas are located in a multiple-input multiple-output (MIMO) system.
A device for detecting pedestrians, characterized in that it includes a processor and a memory, the processor is coupled to the memory, the memory is used to store computer programs or instructions, and the processor is used to execute the memory in the memory said computer program or instructions, causing the method described in any one of claims 10 to 17 to be performed.
A radar, characterized in that it includes a receiver and a processor, the receiver is used to receive multiple received echo signals, and the processor is used to perform any one of claims 10 to 17 according to the echo signals method described in the item.
A vehicle, characterized by comprising the radar system according to any one of claims 1 to 9, or comprising the radar according to claim 19.
A computer-readable storage medium, characterized by storing computer programs or instructions, the computer programs or instructions being used to implement the method according to any one of claims 10-17.