A radar signal processing unit and a waveform processing method

Abstract

A radar signal processing unit (100) applied to a millimeter wave radar and a waveform processing method. The radar signal processing unit (100) comprises: a processing circuit (10), a digital signal processor (20) and a hardware acceleration circuit (300), wherein the processing circuit (10) is used to generate configurable waveform parameters, and configure the transmission parameters of a radio frequency unit (200) coupled to the radar signal processing unit (100) according to the waveform parameters, so that the radio frequency unit (200) transmits a detection signal based on the transmission parameters; the digital signal processor (20) is used to obtain the waveform parameters and send them to the hardware acceleration circuit (300); the hardware acceleration circuit (300) is used to receive an echo signal of the detection signal from the radio frequency unit (200), and based on the waveform parameters, perform range-Doppler dimension calculation on the echo signal to obtain a detection result. The radar signal processing unit (100) and the waveform processing method can support and process different waveforms.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a radar signal processing unit and a waveform processing method. Background Art

[0002] With the continuous development of autonomous driving technology, more and more vehicles are equipped with millimeter wave radars. Millimeter wave radars are sensors that can quickly sense the distance, speed, angle and other information of surrounding objects within a range of 0-200 meters in all-weather scenarios. They play a very important role in autonomous driving. Therefore, more and more autonomous driving systems will adopt millimeter wave radars in the future.

[0003] As millimeter-wave radars become more and more common, when the waveforms emitted by millimeter-wave radars are the same, interference between millimeter-wave radars will be serious. In addition, high-resolution and high-precision 4D radars for autonomous driving (including digital elevation models (DEM), digital orthophoto maps (DOM), digital line graphics (DLG), digital raster graphics (DRG), etc.) are currently hot research topics and important technical directions in the industry, and the measurement accuracy of key measurement indicators such as distance, speed or angle needs to be continuously improved. In this context, by increasing the types of millimeter-wave radar waveforms, interference between millimeter-wave radars can be reduced and the measurement accuracy of millimeter-wave radars can be improved. However, existing millimeter-wave radars find it difficult to support and process different waveforms. Summary of the invention

[0004] The technical problem to be solved by the embodiments of the present application is to provide a radar signal processing unit and a waveform processing method to achieve support and processing of different waveforms.

[0005] In the first aspect, an embodiment of the present application provides a radar processing unit for millimeter wave radar, including: a processing circuit, a digital signal processor and a hardware acceleration circuit, wherein the processing circuit can generate configurable waveform parameters, and then send the waveform parameters to the digital signal processor and a radio frequency unit coupled to the processing circuit, and configure the transmission parameters of the radio frequency unit according to the waveform parameters, so that the radio frequency unit transmits a detection signal based on the transmission parameters. After obtaining the waveform parameters, the digital signal processor can send them to the hardware acceleration circuit, and the hardware acceleration circuit can use the radio frequency unit to receive the echo signal corresponding to the detection signal, and then perform range dimension-Doppler dimension calculation on the echo signal according to the waveform parameters to obtain the detection result.

[0006] In the present application, since the waveform parameters are flexibly configurable, multiple waveforms or even a combination of multiple waveforms can be realized by configuring different waveform parameters, so that the millimeter wave radar can realize the generation, transmission and reception of various waveforms, thereby improving the radar's support for different waveforms and its ability to flexibly process them; and the lower-level hardware acceleration circuit can be uniformly scheduled by the digital signal processor, which can further improve the flexibility and real-time performance of radar signal processing.

[0007] In one possible implementation, the waveform parameters include a transmitting antenna type and a cyclic pattern for transmitting the detection signal, wherein the transmitting antenna type is used to represent a waveform transmitted by the transmitting antenna within the length of a chirp signal, and the cyclic pattern is used to represent a cycle of at least one transmitting antenna type.

[0008] The type of transmitting antenna can be used to flexibly design, classify and identify single waveforms, and the design of cyclic patterns can be used to combine and cycle transmitting antenna types, resulting in more complex and flexible waveforms. This greatly increases the number of waveforms that millimeter-wave radar can support, and can be achieved through simple configuration of waveform parameters, with lower requirements on hardware architecture and cost.

[0009] In one possible implementation, the hardware acceleration circuit includes a distance dimension Fourier transform FFT module; the distance dimension FFT module is used to parse the echo signal according to the cyclic pattern and the transmitting antenna type, extract the distance dimension information and Doppler dimension information of the echo signal, perform cube classification on the echo signal according to the distance dimension information and the Doppler dimension information and determine the storage address of the echo signal, store each type of cube in a memory according to the cube classification result and the storage address, and send the cube classification result and the storage address to the digital signal processor.

[0010] In a possible implementation, the radar signal processing unit also includes a Doppler dimension FFT module, and the digital signal processor is also used to receive the cube classification result and storage address sent by the distance dimension FFT module, and call the Doppler dimension FFT module to perform Doppler dimension FFT processing on each type of cube according to the cube classification result.

[0011] Through subframe-cube layered processing, each subframe can be configured with different waveforms or services, thereby achieving flexible configuration of different services and improving the flexibility of radar service switching. Sub-cube processing can optimize the processing efficiency of subsequent hardware and achieve high efficiency of flexible waveform processing.

[0012] In one possible implementation, the transmitting antenna type is determined based on any one of the following: chirp signal length; waveform shape; Doppler velocity with the same transmitting antenna and the same chirp signal length; Doppler accuracy with the same transmitting antenna and the same chirp signal length; and Doppler functionality with the same transmitting antenna and the same chirp signal length.

[0013] Through the transmission antenna type and the cyclic pattern, various flexible waveforms and waveform combinations can be generated, which also provides a basis for waveform recognition and classification processing.

[0014] In a possible implementation, the sizes of the range-Doppler spectra of cubes of the same category are the same.

[0015] The efficiency of radar signal processing can be improved by classifying and centralizing the cubes.

[0016] In one possible implementation, the distance-dimensional FFT module is specifically used to process each chirp signal in the echo signal separately according to the following method when determining the storage address of the echo signal: determine the transmitting antenna type to which the currently processed chirp signal in the echo signal belongs according to the transmitting antenna type and the cyclic pattern; query the corresponding chirp signal length according to the transmitting antenna type to which the currently processed chirp signal belongs; output an algorithm parameter identifier according to the chirp signal length; determine the calculation parameters of the storage address according to the algorithm parameter identifier; and calculate the storage address of the currently processed chirp signal according to a preset algorithm and the calculation parameters.

[0017] Through signal recognition and classification storage, it is beneficial to the storage and call processing of chirp signals of the same type, providing a good foundation for subsequent distance-dimensional FFT and CFAR processing, and improving the processing flexibility and efficiency of flexible waveforms.

[0018] In a possible implementation manner, the range dimension FFT module is specifically configured to store the echo signal in a memory according to a storage format of transmit antenna information, transmit antenna type information, range dimension information, and Doppler dimension information.

[0019] In one possible implementation, the processing circuit generates configurable waveform parameters, specifically including: determining and generating configurable waveform parameters based on radar detection performance, wherein the waveform parameters are used to represent the waveform parameters of the detection signal transmitted within a frame or to represent the waveform parameters of the detection signal transmitted within a subframe.

[0020] In the second aspect, an embodiment of the present application provides a method for waveform processing applied to a millimeter-wave radar, comprising: first generating configurable waveform parameters, and then configuring the transmission parameters of a radio frequency unit coupled to the radar signal processing unit according to the waveform parameters, so that the radio frequency unit transmits a detection signal based on the transmission parameters; then receiving an echo signal of the detection signal from the radio frequency unit, and performing a range dimension-Doppler dimension calculation on the echo signal based on the waveform parameters to obtain a detection result.

[0021] In one possible implementation, the waveform parameters include a transmitting antenna type and a cyclic pattern for transmitting the detection signal, wherein the transmitting antenna type is used to represent a waveform transmitted by the transmitting antenna within the length of a chirp signal, and the cyclic pattern is used to represent a cycle of at least one transmitting antenna type.

[0022] In a possible implementation, the echo signal is subjected to distance dimension-Doppler dimension calculation based on the waveform parameters to obtain a detection result, including: parsing the echo signal according to the cyclic pattern and the transmitting antenna type, extracting the distance dimension information and Doppler dimension information of the echo signal, performing cube classification on the echo signal according to the distance dimension information and the Doppler dimension information and determining a storage address of the echo signal, storing each type of cube in a memory according to the cube classification result and the storage address, and performing Doppler dimension FFT processing on each type of cube according to the cube classification result.

[0023] In one possible implementation, the transmitting antenna type is determined based on any one of the following: chirp signal length; waveform shape; Doppler velocity with the same transmitting antenna and the same chirp signal length; Doppler accuracy with the same transmitting antenna and the same chirp signal length; and Doppler functionality with the same transmitting antenna and the same chirp signal length.

[0024] In a possible implementation, the sizes of the range-Doppler (RD) spectra of cubes of the same category are the same.

[0025] In one possible implementation, determining the storage address of the echo signal specifically includes processing each chirp signal in the echo signal separately according to the following method: determining the transmitting antenna type to which the currently processed chirp signal in the echo signal belongs according to the transmitting antenna type and the cyclic pattern; querying the corresponding chirp signal length according to the transmitting antenna type to which the currently processed chirp signal belongs; outputting an algorithm parameter identifier according to the chirp signal length; determining the calculation parameters of the storage address according to the algorithm parameter identifier; and calculating the storage address of the currently processed chirp signal according to a preset algorithm and the calculation parameters.

[0026] In a possible implementation, storing each type of cube in a memory according to the cube classification result and the storage address includes: storing the echo signal in a memory according to the storage format of transmitting antenna information, transmitting antenna type information, distance dimension information and Doppler dimension information according to the cube classification result and the storage address.

[0027] In one possible implementation, the generating of configurable waveform parameters includes: determining and generating configurable waveform parameters based on radar detection performance, wherein the waveform parameters are used to represent waveform parameters of a detection signal transmitted within a frame or used to represent waveform parameters of a detection signal transmitted within a subframe.

[0028] In the third aspect, an embodiment of the present application provides a waveform processing device, comprising: a processing unit, used to generate configurable waveform parameters, and configure the transmission parameters of a radio frequency unit coupled to the radar signal processing unit according to the waveform parameters, so that the radio frequency unit transmits a detection signal based on the transmission parameters; a transceiver unit, used to receive an echo signal of the detection signal from the radio frequency unit; the processing unit is also used to perform range dimension-Doppler dimension calculation on the echo signal based on the waveform parameters to obtain a detection result.

[0029] In one possible implementation, the waveform parameters include a transmitting antenna type and a cyclic pattern for transmitting the detection signal, wherein the transmitting antenna type is used to represent a waveform transmitted by the transmitting antenna within the length of a chirp signal, and the cyclic pattern is used to represent a cycle of at least one transmitting antenna type.

[0030] In one possible implementation, the processing unit is specifically used to: parse the echo signal according to the cyclic pattern and the transmitting antenna type, extract the distance dimension information and Doppler dimension information of the echo signal, perform cube classification on the echo signal according to the distance dimension information and the Doppler dimension information and determine the storage address of the echo signal, store each type of cube in a memory according to the cube classification result and the storage address, and perform Doppler dimension FFT processing on each type of cube according to the cube classification result.

[0031] In one possible implementation, the transmitting antenna type is determined based on any one of the following: chirp signal length; waveform shape; Doppler velocity with the same transmitting antenna and the same chirp signal length; Doppler accuracy with the same transmitting antenna and the same chirp signal length; and Doppler functionality with the same transmitting antenna and the same chirp signal length.

[0032] In a possible implementation, the sizes of the range-Doppler spectra of cubes of the same category are the same.

[0033] In one possible implementation, the processing unit determines the storage address of the echo signal, and is specifically used to process each chirp signal in the echo signal separately according to the following method: determine the transmitting antenna type to which the currently processed chirp signal in the echo signal belongs according to the transmitting antenna type and the cyclic pattern; query the corresponding chirp signal length according to the transmitting antenna type to which the currently processed chirp signal belongs; output an algorithm parameter identifier according to the chirp signal length; determine the calculation parameters of the storage address according to the algorithm parameter identifier; and calculate the storage address of the currently processed chirp signal according to a preset algorithm and the calculation parameters.

[0034] In a possible implementation, the processing unit is specifically configured to: store the echo signal in a storage format of transmitting antenna information, transmitting antenna type information, distance dimension information, and Doppler dimension information according to the cube classification result and the storage address.

[0035] In one possible implementation, the processing unit is also used to determine and generate configurable waveform parameters based on radar detection performance, and the waveform parameters are used to represent the waveform parameters of the detection signal transmitted within a frame or to represent the waveform parameters of the detection signal transmitted within a subframe.

[0036] In a fourth aspect, an embodiment of the present application provides a waveform processing device, which may include:

[0037] A processor, a memory and a bus, wherein the processor and the memory are connected via a bus, wherein the memory is used to store a set of program codes, and the processor is used to call the program codes stored in the memory to execute the steps in the second aspect of the embodiment of the present application or any implementation method of the second aspect.

[0038] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein instructions are stored in the computer-readable storage medium, and when the computer-readable storage medium is executed on a computer, the method described in the second aspect or any implementation method of the second aspect is implemented.

[0039] In a sixth aspect, an embodiment of the present application provides a computer program product, comprising: a computer program code, when the computer program code is run on a computer, the computer executes the method in the above-mentioned second aspect and any possible implementation of the second aspect.

[0040] In the seventh aspect, an embodiment of the present application provides a millimeter-wave radar, comprising: a radar signal processing unit as described in the first aspect or any implementation method of the first aspect; and a radio frequency unit coupled to the radar signal processing unit, for transmitting a detection signal based on the transmission parameters configured by the radar signal processing unit; receiving an echo signal of the detection signal, and sending the echo signal to the radar signal processing unit for range dimension-Doppler dimension calculation to obtain a detection result. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0042] Figure 1 A schematic diagram of a system architecture used in an embodiment of the present application;

[0043] Figure 2 A schematic diagram of the architecture of a radar signal processing unit provided in an embodiment of the present application;

[0044] Figure 3 A schematic diagram of a waveform configured with multiple service types in a frame-subframe provided in an embodiment of the present application;

[0045] Figure 4 A schematic diagram of a waveform provided for this application;

[0046] Figure 5 A schematic diagram of another waveform provided for this application;

[0047] Figure 6 A schematic diagram of a waveform combination provided in this application;

[0048] Figure 7 A schematic diagram of a waveform storage structure provided for this application;

[0049] Figure 8 A schematic diagram of different cubes in a waveform provided by the present application;

[0050] Fig. 9 A flowchart of a waveform processing method provided in an embodiment of the present application;

[0051] Fig.10 A schematic diagram of the architecture of a waveform processing device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0052] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0053] The terms "including" and "having" and any variations thereof in the specification and claims of the present application and the above drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0054] The principle of millimeter wave radar ranging is as follows: the radar first sends out radio waves (millimeter waves), then receives the echo, and measures the position data and relative distance of the target based on the time difference between sending and receiving. According to the propagation speed of electromagnetic waves, the distance formula of the target can be determined as follows: s = ct / 2, where s is the target distance, t is the time from the electromagnetic wave being sent out by the radar to the target echo being received, and c is the speed of light. Millimeter wave radar speed measurement is based on the principle of the Doppler effect. When a vibration source such as sound, light, and radio waves moves with an observer at a relative speed v, the vibration frequency received by the observer is different from the frequency emitted by the vibration source. In other words, when the emitted electromagnetic wave and the detected target move relative to each other, the frequency of the echo will be different from the frequency of the emitted wave. When the target approaches the radar antenna, the frequency of the reflected signal will be higher than the frequency of the transmitted signal; conversely, when the target moves away from the antenna, the frequency of the reflected signal will be lower than the frequency of the transmitted signal. The frequency change caused by the Doppler effect is called the Doppler shift, which is proportional to the relative speed v and inversely proportional to the frequency of the vibration. In this way, by detecting this frequency difference, the moving speed of the target relative to the radar can be measured, that is, the relative speed between the target and the radar. As the number of millimeter-wave radars increases, more and more waveforms or waveform combinations are used to avoid interference, which puts higher requirements on the waveform processing of millimeter-wave radars.

[0055] Please refer to Figure 1 , is a schematic diagram of a system architecture used in an embodiment of the present invention. It may include a radar signal processing unit (RSPU) 100 and a radio frequency unit 200. The radar signal processing unit 100 is mainly used to process the received waveform.

[0056] The radio frequency unit 200, which can also be called an antenna, a radio frequency module or a transceiver, can be implemented by a monolithic microwave integrated circuit (MMIC). It can be used to transmit and receive signals. Figure 1 The processing circuit 10 is instructed to send out a detection signal of a specific waveform to measure distance, speed, direction, etc.

[0057] RSPU100 may include: a processing circuit 10, a digital signal processor (DSP) 20, a distance-dimensional Fourier transform (FFT) module 30, a memory 40, a Doppler Fourier transform module 50, and a coherent integration (CI) / constant false alarm rate detection module (CFAR) 60.

[0058] The processing circuit 10 may be a central processing unit (CPU), a microprocessor (MPU), or an application specific integrated circuit (ASIC). When the processing circuit 10 is a processor, it may be a single-core or multi-core processor, which may store various waveform parameters in advance, or generate waveform parameters according to business needs or radar detection performance or user selection and send the waveform parameters to the radio frequency unit 200, so that the radio frequency unit 200 sends out a detection signal that meets the waveform parameters. It may also send the waveform parameters to the DSP 20, and the DSP 20 schedules the various hardware accelerators (HAC) contained in the hardware acceleration circuit, such as the distance dimension FFT module 30, the Doppler dimension FFT module 50, etc., to identify, classify and process the echo signals of the received detection signals.

[0059] The DSP 20 can receive the waveform parameters sent by the processing circuit 10 and notify other HACs, and schedule the corresponding HACs to complete the waveform processing method in this embodiment, thereby supporting and flexibly processing various waveforms.

[0060] The range-dimensional Fourier transform module 40 is mainly used to perform range-dimensional FFT processing on the received echo signal, and store the processed waveform in the memory 50 according to classification. Optionally, the signal after range-dimensional FFT processing can also be cube-classified, and the storage address and classification result can be reported to DSP20 so that DSP20 can perform subsequent scheduling processing. Alternatively, only the storage address can be reported and DSP20 can perform Cube classification.

[0061] The memory 40 may be used to store data processed by the distance dimension FFT.

[0062] The Doppler dimension FFT module 50 may be used to perform Cube-based Doppler dimension FFT processing on the signal after the range dimension FFT processing, and then output it to the CI / CFAR module 60 for related processing.

[0063] The following is a detailed introduction to the composition and execution method of RSPU100.

[0064] See also Figure 2 , is a schematic diagram of the architecture of a radar signal processing unit provided in an embodiment of the present application, including:

[0065] The processing circuit 10 is used to generate configurable waveform parameters and configure the transmission parameters of the radio frequency unit coupled to the radar signal processing unit according to the waveform parameters, so that the radio frequency unit transmits the detection signal based on the transmission parameters.

[0066] The waveform parameters include the type of transmitting antenna for transmitting the detection signal and a cyclic pattern, wherein the type of transmitting antenna is used to represent the waveform transmitted by the transmitting antenna within the length of a chirp signal, and the cyclic pattern is used to represent the cycle of at least one transmitting antenna type.

[0067] The configurable waveform parameters can be flexibly configured according to the detection performance requirements of the radar, such as the detection distance, accuracy, range, etc. It can also be flexibly configured according to different business requirements such as long-range detection business, short-range detection business or listening business, and can also be flexibly configured by the user according to their own needs, without any limitation here.

[0068] The digital signal processor 20 is used to obtain the waveform parameters and send them to the hardware acceleration circuit 300 .

[0069] The hardware acceleration circuit 300 is used to receive the echo signal of the detection signal from the radio frequency unit, and perform range dimension-Doppler dimension calculation on the echo signal based on the waveform parameters to obtain a detection result.

[0070] Optionally, the hardware acceleration circuit 300 includes a distance dimension FFT module 30, and the distance dimension FFT module 30 is used to parse the echo signal according to the cyclic pattern and the transmitting antenna type, extract the distance dimension information and Doppler dimension information of the echo signal, perform cube classification on the echo signal according to the distance dimension information and the Doppler dimension information and determine the storage address of the echo signal, store each type of cube in the memory 40 according to the cube classification result and the storage address, and send the cube classification result and the storage address to the digital signal processor 20.

[0071] Furthermore, the radar signal processing unit also includes a Doppler dimension FFT module 50, and the digital signal processor 20 is also used to receive the cube classification result and storage address sent by the distance dimension FFT module 30, and call the Doppler dimension FFT module 50 to perform Doppler dimension FFT processing on each type of cube according to the cube classification result.

[0072] The memory 40 is used to store the data of the echo signal according to the storage address determined by the distance dimension FFT module.

[0073] Optionally, the waveform parameters received by the processing circuit 10 may be waveform parameters of a detection signal transmitted within a frame (which may be referred to as frame-level waveform parameters), or waveform parameters of a detection signal transmitted within a subframe (which may be referred to as subframe-level waveform parameters). The processing circuit 10 may send these waveform parameters to the RF unit and the digital signal processor 20.

[0074] One frame can contain multiple subframes, such as 4 subframes, and each subframe can be configured with independent subframe-level waveform parameters, thereby realizing a hierarchical processing mechanism from frame to subframe.

[0075] If the processing circuit 10 sends frame-level waveform parameters to the digital signal processor 20, the digital signal processor 20 may parse the frame-level waveform parameters to obtain sub-frame-level waveform parameters of each sub-frame contained therein.

[0076] After processing the echo signal corresponding to the detection signal transmitted in the first subframe, the digital signal processor 20 is further used to:

[0077] Obtaining subframe-level waveform parameters corresponding to the second subframe;

[0078] An echo signal corresponding to the detection signal transmitted on the second subframe is processed according to the subframe-level waveform parameter corresponding to the second subframe.

[0079] If a third subframe is further included, similar processing is performed on the third subframe in sequence.

[0080] The hierarchical processing mode can be found in Figure 3 , is a schematic diagram of a waveform of a frame-subframe multiple service type configuration provided in an embodiment of the present application. Figure 3As shown, the frame includes a total of 4 subframes, namely, the first subframe, the second subframe, the third subframe and the fourth subframe, which correspond to different services respectively, such as the first subframe corresponds to the listening service, the second subframe corresponds to the long-range target detection service, the third subframe corresponds to the medium-range target detection service, and the fourth subframe corresponds to the calibration / measurement service, and each subframe has its own independent waveform configuration. The waveform of each subframe can be the same or different, and can be sent and received sequentially on a single antenna or multiple antennas using time division multiplexing (TDM) or code division multiplexing (CDM).

[0081] In the embodiment of the present application, since it is necessary to support the processing of multiple waveforms, the multiple waveforms can be firstly identified and classified by the range dimension FFT module. The transmit antenna type (Tx Ant Type) can be defined to classify different waveforms.

[0082] Optionally, the transmitting antenna type is determined according to any one of the following:

[0083] Chirp signal length;

[0084] Waveform shape;

[0085] The speed in the Doppler dimension for the same transmitting antenna and the same chirp signal length;

[0086] The accuracy of Doppler dimension for the same transmitting antenna and the same chirp signal length;

[0087] Function of the Doppler wavelength for the same transmit antenna and the same chirp signal length.

[0088] For example, see Figure 4-Figure 5 , which is a schematic diagram of various waveforms. Figure 4 As shown in the figure, the chirp signal has different lengths. Figure 5 The following are waveform types with different chirp signal waveform shapes. The classification of the same transmitting antenna and the same chirp signal length can be classified according to the speed, accuracy or function of the Doppler dimension, for example, see Figure 3 , where the transmitting antennas of the first subframe and the fourth subframe are the same and the chirp signal lengths are also the same, then they can be classified according to their different service functions.

[0089] Furthermore, a plurality of different waveforms may be combined to obtain a combined waveform. For the combined waveform, a loop pattern may be used to distinguish, which may define how many groups of transmit antenna types are cycled in a subframe. Optionally, the loop pattern includes at least one transmit antenna type.

[0090] Taking 4-antenna time division multiplexing and one transmitting 512 chirp signals as an example, if the Loop pattern is {TX1, TX2, TX3, TX4}, the cycle period is 4, and the number of cycle groups is 512 / 4=128. If the Loop pattern is {TX1, TX2, TX3, TX4, TX4, TX3, TX2, TX1}, the cycle period is 8 and the number of sequential groups is 512 / 8=64.

[0091] That is, taking the transmitting antenna type (Tx ant Type) as the granularity, a total of N chirp signals are transmitted, the loop pattern is {Tx ant Type0, Tx ant Type1, Tx ant Type2, ..., Tx ant TypeN}, then the cycle period is N_Tx_ant_type, and the number of cycle groups is N chirp / N_Tx_ant_type.

[0092] Furthermore, in one subframe, there may be multiple sets of Loop patterns, such as Loop pattern 1, Loop pattern 2, and so on.

[0093] For examples of Tx Ant Type and Loop pattern, see Figure 6 , which shows two loop patterns, one containing Tx ant Type0 / 1 / 2 / 3 / 4 / 5 / 6 / 7, and the other containing Tx ant Type0 / 2 / 3 / 4 / 5 / 7.

[0094] Tx Ant type0 is configured as 4 antennas ( Figure 6 Tx ant Type1 is configured with code division multiplexing of four antennas (T4 to T7), and Tx ant Type2 is configured with single antenna time division multiplexing (T0).

[0095] Through the transmission antenna type and the cyclic pattern, various flexible waveforms and waveform combinations can be generated, which also provides a basis for waveform recognition and classification processing.

[0096] The distance dimension FFT module 30 is specifically used to process each chirp signal in the echo signal according to the following method when determining the storage address of the echo signal:

[0097] Determine, according to the transmitting antenna type and the cyclic pattern, the transmitting antenna type to which the currently processed chirp signal in the echo signal belongs;

[0098] Querying the corresponding chirp signal length according to the type of transmitting antenna to which the currently processed chirp signal belongs;

[0099] Outputting an algorithm parameter identifier according to the chirp signal length;

[0100] Determine a calculation parameter of a storage address according to the algorithm parameter identifier;

[0101] The storage address of the currently processed chirp signal is calculated according to a preset algorithm and the calculation parameters.

[0102] The specific classification process may include:

[0103] (1) Analyze waveform parameters;

[0104] (2) When receiving the data of each chirp signal, determine which Tx ant Type the current chirp belongs to based on the Loop pattern:

[0105] (3) Query the chirp signal length of the Tx ant type;

[0106] (4) Output the algorithm parameter ID of the Tx ant type (such as window coefficient, FFT size) to the internal submodule;

[0107] (5) Calculate the offset address of the current chirp data output, i.e., the storage address;

[0108] (6) Output the chirp data and message; the message contains the subframe number, chirp number, and Tx ant type number;

[0109] (7) Doppler count of each type +1;

[0110] (8) Determine whether the sending of the chirp signal of this type has ended;

[0111] (9) The chirp transmission counts of each type are accumulated to determine whether the maximum number of chirps has been reached. If reached, a subframe end message is sent.

[0112] The distance dimension FFT module 30 may be preconfigured to determine the number of chirps after which a message is sent.

[0113] The storage format of the echo signal output by the range dimension FFT module 30 can be found in Figure 7 ,like Figure 7As shown, two transmitting antennas (including transmitting antenna 0 and transmitting antenna 1) and two transmitting antenna types (transmitting antenna type 0 and transmitting antenna similar to 1) are used as examples for explanation. The chirp length and Doppler dimension length of the two transmitting antenna types are different, so each transmitting antenna type is stored independently. As shown in the above processing flow, when the distance dimension FFT module 30 receives each chirp data, it determines which transmitting antenna type the chirp belongs to and outputs the offset address. Finally, each flexible waveform is parsed and stored through the storage format of the transmitting antenna, transmitting antenna type, distance dimension, and Doppler dimension. Among them, the chirp number is used to indicate the number of the chirp signal, and M and N are used to indicate the number of chirp signals in each storage organization structure.

[0114] Through the signal recognition and classification storage in this embodiment, the storage and call processing of chirp signals of the same type are facilitated, providing a good foundation for subsequent distance-dimensional FFT and CFAR processing, and improving the processing flexibility and efficiency of flexible waveforms.

[0115] When classifying cubes, the distance-Doppler spectra of cubes of the same category have the same size. If there are physically 2 transmitting antennas and 4 receiving antennas, 2*4=8 virtual antennas can be combined. Since the length / Doppler dimension length of the chirp signal changes, the distance-Doppler spectra (RD map) will eventually be different. Therefore, virtual antennas with the same RD map shape can be regarded as a kind of cube, and cubes of different shapes are processed separately. For the length / Doppler dimension length of the chirp signal, since multiple subframes can carry different services respectively, each subframe may contain 2 or more waveforms, resulting in multiple cubes after the distance dimension FFT, such as RD map 512*512, RD map 512*256, RD map512*128, etc. In this way, the cubes can be classified and further centralized processing after classification is performed to achieve hierarchical processing of frame-subframe-cube.

[0116] See also Figure 8 , which is a schematic diagram of different cubes in a waveform provided by an embodiment of the present application, such as Figure 8As shown, it can correspond to a waveform in a subframe, which is transmitted in a 4-antenna time division multiplexing manner. Among them, the Doppler dimension length of the virtual antenna T0 accounts for half, and the sum of the Doppler dimension lengths of the virtual antennas T1 / T2 / T3 accounts for the other half. RDmap forms two shapes: T0 RD (1024*384) Cube1, T1~T3 RD (1024*128) Cube2, so the subframe forms 2 types of Cubes, and in subsequent Doppler dimension FFT and CFAR and other processing, they can be processed separately according to the classification of different cubes. The Cube shape parameters 1024*384 and 1024*128 here are only used as examples, and they can also be other parameters, which are not limited in any way in the embodiments of the present application. In addition, Figure 7 The waveform shown is obtained by combining waveforms transmitted by a total of four virtual antennas T0 to T3. In actual scenarios, waveforms transmitted by two or more virtual antennas may be combined, and the combined waveform may include two or more types of Cubes.

[0117] In the embodiments of the present application, the radar's processing capability for flexible waveforms is improved through flexible classification of waveforms and waveform combinations; through layered processing of frame-subframe-cube, each subframe can be configured with different waveforms or services, thereby achieving flexible configuration of different services and improving the flexibility of radar service switching; and the lower-level hardware accelerators are uniformly scheduled by the DSP, which can further improve the flexibility and real-time performance of radar signal processing.

[0118] For details on how to implement RSPU100, please refer to Fig. 9 , Fig. 9 A flowchart of a waveform processing method provided in an embodiment of the present application; specifically comprising the following steps:

[0119] S901. Generate configurable waveform parameters, and configure transmission parameters of a radio frequency unit coupled to the radar signal processing unit according to the waveform parameters, so that the radio frequency unit transmits a detection signal based on the transmission parameters.

[0120] The subframe-level waveform parameters include the transmitting antenna type and the cycle pattern for transmitting the detection signal, the transmitting antenna type is used to represent the waveform transmitted by the transmitting antenna within the length of a chirp signal, and the cycle pattern is used to represent the cycle of at least one transmitting antenna type.

[0121] S902. Receive an echo signal of the detection signal from the radio frequency unit, and perform range dimension-Doppler dimension calculation on the echo signal based on the waveform parameters to obtain a detection result.

[0122] In step S902, based on the waveform parameters, performing range dimension-Doppler dimension calculation on the echo signal to obtain a detection result includes:

[0123] The echo signal is parsed according to the cyclic pattern and the type of transmitting antenna, and the distance dimension information and Doppler dimension information of the echo signal are extracted. The echo signal is cube-classified according to the distance dimension information and the Doppler dimension information and the storage address of the echo signal is determined. Each type of cube is stored in a memory according to the cube classification result and the storage address.

[0124] According to the cube classification results, Doppler FFT processing is performed on each type of cube.

[0125] Optionally, the transmitting antenna type is determined according to any one of the following:

[0126] Chirp signal length;

[0127] Waveform shape;

[0128] The speed in the Doppler dimension for the same transmitting antenna and the same chirp signal length;

[0129] The accuracy of Doppler dimension for the same transmitting antenna and the same chirp signal length;

[0130] Function of the Doppler wavelength for the same transmit antenna and the same chirp signal length.

[0131] Among them, the distance-Doppler (RD) spectra of the same category of cubes have the same size.

[0132] Optionally, the determining the storage address of the echo signal specifically includes processing each chirp signal in the echo signal respectively according to the following method:

[0133] Determine, according to the transmitting antenna type and the cyclic pattern, the transmitting antenna type to which the currently processed chirp signal in the echo signal belongs;

[0134] Querying the corresponding chirp signal length according to the type of transmitting antenna to which the currently processed chirp signal belongs;

[0135] Outputting an algorithm parameter identifier according to the chirp signal length;

[0136] Determine a calculation parameter of a storage address according to the algorithm parameter identifier;

[0137] The storage address of the currently processed chirp signal is calculated according to a preset algorithm and the calculation parameters.

[0138] Optionally, storing each type of cube in a memory according to the cube classification result and the storage address includes:

[0139] According to the cube classification result and the storage address, the echo signal is stored in a memory in a storage format according to the transmitting antenna information, the transmitting antenna type information, the distance dimension information and the Doppler dimension information.

[0140] Optionally, the generating of configurable waveform parameters includes:

[0141] The configurable waveform parameters are determined and generated according to the radar detection performance, and the waveform parameters are used to represent the waveform parameters of the detection signal transmitted in a frame or used to represent the waveform parameters of the detection signal transmitted in a subframe.

[0142] Optionally, the method further comprises:

[0143] Obtaining subframe-level waveform parameters corresponding to the second subframe included in the waveform parameters;

[0144] The echo signal corresponding to the detection signal transmitted in the second subframe is processed according to the subframe-level waveform parameter corresponding to the second subframe.

[0145] For specific waveform recognition, classification and processing methods, please refer to Figure 2 The description of related contents will not be repeated here.

[0146] Please refer to Fig.10 , is a schematic diagram of the architecture of a waveform processing device provided in an embodiment of the present application; it may include:

[0147] The processing unit 1000 is configured to generate configurable waveform parameters, and configure the transmission parameters of the radio frequency unit coupled to the radar signal processing unit according to the waveform parameters, so that the radio frequency unit transmits the detection signal based on the transmission parameters;

[0148] The transceiver unit 2000 is used to receive the echo signal of the detection signal from the radio frequency unit;

[0149] The processing unit 1000 is further configured to perform range dimension-Doppler dimension calculation on the echo signal based on the waveform parameters to obtain a detection result.

[0150] Optionally, the waveform parameters include a transmitting antenna type and a cyclic pattern for transmitting the detection signal, the transmitting antenna type is used to represent a waveform transmitted by the transmitting antenna within the length of a chirp signal, and the cyclic pattern is used to represent a cycle of at least one transmitting antenna type.

[0151] Optionally, the processing unit 1000 is specifically configured to:

[0152] The echo signal is parsed according to the cyclic pattern and the type of transmitting antenna, and the distance dimension information and Doppler dimension information of the echo signal are extracted. The echo signal is cube-classified according to the distance dimension information and the Doppler dimension information and the storage address of the echo signal is determined. Each type of cube is stored in a memory according to the cube classification result and the storage address, and Doppler dimension FFT processing is performed on each type of cube according to the cube classification result.

[0153] Optionally, the transmitting antenna type is determined according to any one of the following:

[0154] Chirp signal length;

[0155] Waveform shape;

[0156] The speed in the Doppler dimension for the same transmitting antenna and the same chirp signal length;

[0157] The accuracy of Doppler dimension for the same transmitting antenna and the same chirp signal length;

[0158] Function of the Doppler wavelength for the same transmit antenna and the same chirp signal length.

[0159] Optionally, the range-Doppler spectra of cubes of the same category have the same size.

[0160] Optionally, the processing unit 1000 determines the storage address of the echo signal, specifically for processing each chirp signal in the echo signal respectively according to the following method:

[0161] Determine, according to the transmitting antenna type and the cyclic pattern, the transmitting antenna type to which the currently processed chirp signal in the echo signal belongs;

[0162] Querying the corresponding chirp signal length according to the type of transmitting antenna to which the currently processed chirp signal belongs;

[0163] Outputting an algorithm parameter identifier according to the chirp signal length;

[0164] Determine a calculation parameter of a storage address according to the algorithm parameter identifier;

[0165] The storage address of the currently processed chirp signal is calculated according to a preset algorithm and the calculation parameters.

[0166] Optionally, the processing unit 1000 is specifically configured to: store the echo signal in a storage format of transmitting antenna information, transmitting antenna type information, distance dimension information and Doppler dimension information in a memory according to the cube classification result and the storage address.

[0167] Optionally, the processing unit 1000 is also used to determine and generate configurable waveform parameters based on radar detection performance, and the waveform parameters are used to represent the waveform parameters of the detection signal transmitted in a frame or the waveform parameters of the detection signal transmitted in a subframe. The concepts, explanations, detailed descriptions and other steps related to the technical solution provided in the embodiment of the present application involved in the waveform processing device can be found in the description of the contents of RSPU in the aforementioned method or other embodiments, which will not be repeated here.

[0168] Those skilled in the art will appreciate that for ease of description, Figure 2 Only one memory and central processing unit are shown. In actual scenarios, there may be multiple processors and memories. The memory may also be referred to as a storage medium or a storage device, etc., which is not limited in the embodiments of the present application.

[0169] The memory may include a read-only memory and a random access memory, and provides instructions and data to the processor. A portion of the memory may also include a nonvolatile random access memory.

[0170] In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the method disclosed in conjunction with the embodiment of the present application can be directly embodied as a hardware processor for execution, or a combination of hardware and software modules in a processor for execution. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it is not described in detail here.

[0171] According to the RSPU, method and device provided in the embodiment of the present application, the embodiment of the present application also provides a millimeter wave radar, which includes the aforementioned RSPU 100 and radio frequency unit 200, etc. For details, please refer to Figure 1 As shown, the millimeter wave radar includes RSPU 100 and RF unit 200. The main functions and effects of RSPU 100 can be found in Figure 2 According to the description of the illustrated embodiment, the radio frequency unit 200 is mainly used to receive waveform parameters sent by the central processor 10 in the RSPU 100, and transmit a waveform signal according to the waveform parameters; receive an echo signal, and send the waveform to be processed contained in the echo signal to the RSPU 100 for processing.

[0172] In various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean 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 application.

[0173] Those skilled in the art will appreciate that the various illustrative logical blocks (ILBs) and steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or in a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0174] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0175] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integration. The available medium can be a magnetic medium, (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state hard disk), etc.

[0176] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A radar signal processing unit for millimeter wave radar, It is characterized in that include: A processing circuit, configured to generate configurable waveform parameters, and configure transmission parameters of a radio frequency unit coupled to the radar signal processing unit according to the waveform parameters, so that the radio frequency unit transmits a detection signal based on the transmission parameters; A digital signal processor, used for acquiring the waveform parameters and sending them to a hardware acceleration circuit; The hardware acceleration circuit is used to receive the echo signal of the detection signal from the radio frequency unit, and perform range dimension-Doppler dimension calculation on the echo signal based on the waveform parameters to obtain a detection result; The waveform parameters include a transmitting antenna type and a cyclic pattern for transmitting the detection signal, the transmitting antenna type is used to represent a waveform transmitted by the transmitting antenna within a chirp signal length, and the cyclic pattern is used to represent a cycle of at least one transmitting antenna type; Among them, the hardware acceleration circuit includes a distance dimension Fourier transform FFT module, and the distance dimension FFT module is used to parse the echo signal according to the cyclic pattern and the transmitting antenna type, extract the distance dimension information and Doppler dimension information of the echo signal, cube classify the echo signal according to the distance dimension information and the Doppler dimension information and determine the storage address of the echo signal, store each type of cube in a memory according to the cube classification result and the storage address, and send the cube classification result and the storage address to the digital signal processor.

2. The radar signal processing unit according to claim 1, It is characterized in that The radar signal processing unit also includes a Doppler dimension FFT module, and the digital signal processor is also used to receive the cube classification result and storage address sent by the distance dimension FFT module, and call the Doppler dimension FFT module according to the cube classification result to perform Doppler dimension FFT processing on each type of cube.

3. The radar signal processing unit according to claim 1, It is characterized in that The transmitting antenna type is determined according to any one of the following: Chirp signal length; Waveform shape; The speed in the Doppler dimension for the same transmitting antenna and the same chirp signal length; The accuracy of Doppler dimension for the same transmitting antenna and the same chirp signal length; Function of the Doppler wavelength for the same transmit antenna and the same chirp signal length.

4. The radar signal processing unit according to claim 1, It is characterized in that The range-Doppler spectra of cubes of the same category have the same size.

5. The radar signal processing unit according to claim 1, It is characterized in that The distance dimension FFT module is specifically used to process each chirp signal in the echo signal according to the following method when determining the storage address of the echo signal: Determine, according to the transmitting antenna type and the cyclic pattern, the transmitting antenna type to which the currently processed chirp signal in the echo signal belongs; Querying the corresponding chirp signal length according to the type of transmitting antenna to which the currently processed chirp signal belongs; Outputting an algorithm parameter identifier according to the chirp signal length; Determine a calculation parameter of a storage address according to the algorithm parameter identifier; The storage address of the currently processed chirp signal is calculated according to a preset algorithm and the calculation parameters.

6. The radar signal processing unit according to claim 1, It is characterized in that The range dimension FFT module is specifically used to store the echo signal in a memory according to the storage format of the transmitting antenna information, the transmitting antenna type information, the range dimension information and the Doppler dimension information.

7. The radar signal processing unit according to any one of claims 1 to 6, It is characterized in that The processing circuit generates configurable waveform parameters, specifically including: determining and generating configurable waveform parameters according to radar detection performance, wherein the waveform parameters are used to represent the waveform parameters of the detection signal transmitted within a frame or to represent the waveform parameters of the detection signal transmitted within a subframe.

8. A method for waveform processing applied to millimeter wave radar, It is characterized in that include: Generate configurable waveform parameters, and configure transmission parameters of a radio frequency unit coupled to a radar signal processing unit according to the waveform parameters, so that the radio frequency unit transmits a detection signal based on the transmission parameters; receiving an echo signal of the detection signal from the radio frequency unit, and performing range dimension-Doppler dimension calculation on the echo signal based on the waveform parameters to obtain a detection result; The waveform parameters include a transmitting antenna type and a cyclic pattern for transmitting the detection signal, the transmitting antenna type is used to represent a waveform transmitted by the transmitting antenna within a chirp signal length, and the cyclic pattern is used to represent a cycle of at least one transmitting antenna type; Wherein, based on the waveform parameters, the distance dimension-Doppler dimension calculation is performed on the echo signal to obtain the detection result, including: parsing the echo signal according to the cyclic pattern and the transmitting antenna type, extracting the distance dimension information and Doppler dimension information of the echo signal, performing cube classification on the echo signal according to the distance dimension information and the Doppler dimension information and determining the storage address of the echo signal, and storing each type of cube in a memory according to the cube classification result and the storage address.

9. The method according to claim 8, It is characterized in that The step of performing range dimension-Doppler dimension calculation on the echo signal based on the waveform parameters to obtain a detection result further includes: According to the cube classification results, Doppler FFT processing is performed on each type of cube.

10. The method according to claim 8, It is characterized in that The transmitting antenna type is determined according to any one of the following: Chirp signal length; Waveform shape; The speed in the Doppler dimension for the same transmitting antenna and the same chirp signal length; The accuracy of Doppler dimension for the same transmitting antenna and the same chirp signal length; Function of the Doppler wavelength for the same transmit antenna and the same chirp signal length.

11. The method according to claim 8, It is characterized in that The range-Doppler spectra of cubes of the same category have the same size.

12. The method according to claim 8, It is characterized in that The determining the storage address of the echo signal specifically includes processing each chirp signal in the echo signal respectively according to the following method: Determine, according to the transmitting antenna type and the cyclic pattern, the transmitting antenna type to which the currently processed chirp signal in the echo signal belongs; Querying the corresponding chirp signal length according to the type of transmitting antenna to which the currently processed chirp signal belongs; Outputting an algorithm parameter identifier according to the chirp signal length; Determine a calculation parameter of a storage address according to the algorithm parameter identifier; The storage address of the currently processed chirp signal is calculated according to a preset algorithm and the calculation parameters.

13. The method according to claim 8, It is characterized in that The step of storing each type of cube into a memory according to the cube classification result and the storage address comprises: According to the cube classification result and the storage address, the echo signal is stored in a memory in a storage format according to the transmitting antenna information, the transmitting antenna type information, the distance dimension information and the Doppler dimension information.

14. The method according to any one of claims 8 to 13, It is characterized in that The generating of configurable waveform parameters includes: The configurable waveform parameters are determined and generated according to the radar detection performance, and are used to represent the waveform parameters of the detection signal transmitted in a frame or used to represent the waveform parameters of the detection signal transmitted in a subframe.

15. A millimeter wave radar, It is characterized in that include: The radar signal processing unit according to any one of claims 1 to 7; as well as The radio frequency unit coupled to the radar signal processing unit is used to transmit a detection signal based on the transmission parameters configured by the radar signal processing unit; receive an echo signal of the detection signal, and send the echo signal to the radar signal processing unit for range dimension-Doppler dimension calculation to obtain a detection result.

16. A computer-readable storage medium, It is characterized in that include: The computer-readable storage medium stores instructions, which, when executed on a computer, implement the method according to any one of claims 8 to 14.

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