Speed deambiguating method, device, integrated circuit, radio and terminal equipment

Abstract

A speed deambiguating method, device, integrated circuit, radio device and terminal equipment, for the scenario that the detected target speed is greater than the maximum non-ambiguous speed, by transmitting a probe signal including a triangular wave through an antenna, and according to the frequency difference obtained from the distance-speed two-dimensional spectrum corresponding to the rising section and the falling section of the triangular wave respectively, the real speed of the target is obtained, which can effectively solve the problem of multi-target matching, and can also effectively improve the reliability of speed deambiguating.

Description

Technical Field

[0001] This application relates to, but is not limited to, radar signal processing technology, and more specifically, to a speed deambiguation method, apparatus, integrated circuit, radio device, and terminal equipment. Background Technology

[0002] When using Frequency Modulated Continuous Wave (FMCW) for target velocity detection, if the detected target velocity exceeds the maximum unambiguous velocity, velocity deambiguation is typically achieved by using AB frames. However, this method cannot solve the problem of multi-target matching. Summary of the Invention

[0003] To address the aforementioned technical problems, embodiments of this application provide a velocity de-ambiguity method, apparatus, integrated circuit, wireless device, and terminal equipment. In scenarios where the detected target velocity is greater than the maximum unambiguous velocity, a detection signal including a symmetrical triangular wave can be transmitted via an antenna. The true velocity of the target can be obtained by calculating the frequency difference between the distance and velocity two-dimensional spectra corresponding to the rising and falling segments of the triangular wave, respectively. This effectively solves the problem of multi-target matching and also effectively improves the reliability of velocity de-ambiguity.

[0004] This application provides a velocity deambiguation method applicable to a frequency-modulated continuous wave (FMCW) radar system. Each frame of signal transmitted by the radar system includes a first unit signal constituting the rising segment of a triangular wave and a second unit signal constituting the falling segment of the triangular wave, wherein the first unit signal and the second unit signal have the same period. The method includes: performing range-dimensional FFT on the first unit signal sequence and the second unit signal sequence in the echo signal respectively to obtain the frequency difference of the same target in the range dimension; and determining the velocity of the target based on the frequency difference.

[0005] In some optional embodiments, the method may further include: performing velocity-dimensional FFT on a first unit signal sequence and a second unit signal sequence in the echo signal to obtain the Doppler frequency shift of the target; determining a first unambiguous Doppler component based on the frequency difference; determining a first Doppler ambiguity factor based on the Doppler frequency shift, the first unambiguous Doppler component, and the period of the first unit signal; and determining the velocity of the target based on the first Doppler ambiguity factor.

[0006] In some alternative embodiments, determining the first unambiguous Doppler component based on the frequency difference includes dividing the frequency difference by 2 to obtain the first unambiguous Doppler component.

[0007] In some optional embodiments, the method may further include: performing velocity-dimensional FFT on a first unit signal sequence and a second unit signal sequence in the echo signal to obtain the Doppler frequency shift and difference frequency component of the target; determining a second unambiguous Doppler component based on the frequency difference and the difference frequency component; determining a second Doppler ambiguity factor based on the Doppler frequency shift, the second unambiguous Doppler component, and the period of the first unit signal; and determining the velocity of the target based on the second Doppler ambiguity factor.

[0008] In some optional embodiments, determining the second unambiguous Doppler component based on the frequency difference and the difference frequency component includes: determining the second unambiguous Doppler component by interpolation based on the frequency difference and the difference frequency component.

[0009] In some optional embodiments, obtaining the difference frequency component, and determining the second unambiguous Doppler component based on the frequency difference and the difference frequency component by interpolation, includes: using the sum of half of the frequency difference and the difference frequency component as a first frequency value; using the difference frequency component minus half of the frequency difference as a second frequency value; and interpolating the frequency value and the second frequency value to obtain the second unambiguous Doppler component.

[0010] In some alternative embodiments, for any of the said triangular waves, the rising segment and the falling segment are mirror-symmetrical.

[0011] In some alternative embodiments, the rising and falling segments of the same triangular wave correspond to the rising and falling edges of the same chirp, respectively.

[0012] In some alternative embodiments, the rising and falling segments of the same triangular wave correspond to the rising edge of the previous chirp and the falling edge of the next chirp, respectively, in two adjacent chirps.

[0013] In some alternative embodiments, the radar system is a MIMO radar system; the waveform transmitted in one transmission cycle of the MIMO radar system includes at least one of the triangular waves.

[0014] This application also provides a velocity deambiguation device in a radar system, which may include a memory and a processor. The memory stores a computer program, characterized in that the processor executes the computer program as the velocity deambiguation method based on frequency-modulated continuous wave described in any embodiment.

[0015] This application also provides a non-transient computer-readable storage medium storing a computer program, characterized in that the computer program, when executed by a processor, implements the speed defuzzification method described in any embodiment of this application.

[0016] This application also provides a radar waveform, wherein for any frame of transmitted signal, the radar waveform includes a triangular waveform segment; the triangular waveform segment includes a rising segment and a falling segment with the same period; wherein the rising segment and the falling segment are mirror-symmetrical.

[0017] In some alternative embodiments, the rising and falling segments of the same triangular wave correspond to the rising and falling edges of the same chirp, respectively.

[0018] In some alternative embodiments, the rising and falling segments of the same triangular wave correspond to the rising edge of the previous chirp and the falling edge of the next chirp, respectively, in two adjacent chirps.

[0019] In some alternative embodiments, it is applied to a TD MIMO radar system; the waveform transmitted in one transmission cycle of the TD MIMO radar system includes at least one of the triangular waves.

[0020] In some alternative embodiments, the rising and falling segments of the same triangular waveform segment are transmitted using the same transmitting antenna.

[0021] In some alternative embodiments, velocity deblurring can be performed based on the rising and falling segments of the triangular waveform segment.

[0022] In some optional embodiments, the method described in any embodiment of this application is used to perform velocity deambiguation in the radar system based on the rising segment and the falling segment of the triangular waveform segment.

[0023] This application also provides an integrated circuit, which may include a radio frequency (RF) module, an analog signal processing module, and a digital signal processing module connected in sequence; the RF module is used to generate an RF transmission signal and receive an RF echo signal; the analog signal processing module is used to down-convert the RF echo signal to obtain an intermediate frequency (IF) signal; and the digital signal processing module is used to perform analog-to-digital conversion on the IF signal to obtain a digital signal; wherein, the digital signal processing module further uses the method described in any embodiment of this application to perform speed deambiguation.

[0024] In some alternative embodiments, the integrated circuit may be a millimeter-wave chip.

[0025] This application also provides a wireless device, which may include: a carrier; an integrated circuit as described in any embodiment of this application, disposed on the carrier; an antenna, disposed on the carrier, or the antenna and the integrated circuit are integrated into a single device disposed on the carrier; wherein the integrated circuit is connected to the antenna and is used to transmit the radio frequency transmission signal and / or receive the radio frequency echo signal.

[0026] This application also provides a terminal device, which may include: a device body; and a wireless device as described in any of the embodiments disposed on the device body; wherein the wireless device is used for target detection and / or communication to provide reference information to the operation of the device body.

[0027] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application may be realized and obtained by means of the embodiments described in the description, claims, and drawings. Attached Figure Description

[0028] The accompanying drawings are used to provide an understanding of the technical solutions of this application and form part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application, and do not constitute a limitation on the technical solutions of this application. The shapes and sizes of the components in the drawings do not reflect actual proportions and are only intended to illustrate the content of this application.

[0029] Figure 1 This is a hardware block diagram of a radar system that can be used in embodiments of this application;

[0030] Figure 2 yes Figure 1 A schematic diagram of the transmitting antenna array and the receiving antenna array in the diagram;

[0031] Figure 3 This is a functional block diagram of a radar system that can be used in this embodiment;

[0032] Figure 4 This is a schematic diagram of a chirp signal with a sawtooth waveform;

[0033] Figure 5 This is a schematic diagram of a detection signal emitted by a radar system capable of velocity deambiguity.

[0034] Figure 6 This is a schematic diagram of a detection signal emitted by another radar system capable of velocity deambiguity;

[0035] Figure 7 This is a flowchart of a speed defuzzification method according to an embodiment of this application;

[0036] Figure 8 This is a schematic diagram of a triangular wave signal emitted by a radar system according to an embodiment of this application;

[0037] Figure 9 This is a schematic diagram of a detection signal with a combined waveform emitted by a radar system according to another embodiment of this application;

[0038] Figure 10 This is a schematic diagram illustrating the frequency difference between the transmitted and echo signals when there is relative motion between the radar and the target.

[0039] Figure 11 This is a schematic diagram of the spectral positions in the sampling point matrix obtained after a two-dimensional FFT;

[0040] Figure 12 This is a schematic diagram of a velocity deambiguation device in a radar system according to an embodiment of this application;

[0041] Figure 13 This is a block diagram of an integrated circuit according to an embodiment of this application;

[0042] Figure 14 This is a schematic diagram of a radar system according to an embodiment of this application. Detailed Implementation

[0043] This application describes several embodiments, but these descriptions are exemplary and not restrictive, and it will be apparent to those skilled in the art that there are many more embodiments and implementations within the scope of the embodiments described herein.

[0044] In the description of this application, the words "exemplary" or "for example" are used to indicate that they are examples, illustrations, or descriptions. Any embodiment described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments. The term "and / or" in this document describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. "Multiple" refers to two or more. Furthermore, to facilitate a clear description of the technical solutions of the embodiments of this application, the terms "first" and "second" are used to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that "first" and "second" do not necessarily imply differences.

[0045] In describing representative exemplary embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Furthermore, the claims relating to the method and / or process should not be limited to the steps performed in the order written, and those skilled in the art will readily understand that these orders may be varied and still remain within the spirit and scope of the embodiments of this application.

[0046] This application provides a velocity deambiguation method applicable to frequency-modulated continuous wave (FMCW) radar systems. Each frame of signal transmitted by this radar system may include at least one or more triangular waves (e.g., one triangular wave per transmission cycle, or the number of triangular waves and their distribution parameters in the frame signal are set according to preset rules, as long as they can achieve the velocity deambiguation speed). For example, a waveform segment with opposite slope and identical parameters can be inserted into a conventional waveform structure to form an approximate or equivalent triangular waveform structure. That is, the triangular wave may include a first unit signal and a second unit signal, namely, the first unit signal constituting the rising segment of the triangular wave and the second unit signal constituting the falling segment of the triangular wave, and the period, bandwidth, absolute value of the slope, etc., of the first unit signal and the second unit signal are the same. Operations such as analog-to-digital conversion, sampling, and range-dimensional FFT can be performed on the first unit signal sequence and the second unit signal sequence in the echo signal to obtain the frequency difference of the same target (peak) in the range dimension. Subsequently, the velocity of the target can be determined based on this frequency difference, thus achieving the aforementioned velocity deambiguation.

[0047] For example, the first and second unit signal sequences in the echo signal can be processed by the range-dimensional FFT as described above, and then subjected to velocity-dimensional FFT to obtain the Doppler frequency shift of the target. Based on the frequency difference, the first unambiguous Doppler component can be determined by dividing by 2. That is, the first Doppler ambiguity factor can be determined based on the Doppler frequency shift, the first unambiguous Doppler component, and the period of the first unit signal. Finally, based on the first Doppler ambiguity factor, the velocity of each target can be determined on the basis of the velocity-dimensional FFT, thereby realizing the velocity deambiguation operation.

[0048] Depending on the application scenario, when higher speed measurement accuracy is required, after obtaining the Doppler frequency shift of the target in the above embodiment, the difference frequency component shift is obtained based on the frequency difference and FFT processing, and the second unambiguous Doppler component is determined by means such as interpolation; subsequently, the second Doppler ambiguity factor can be determined based on the Doppler frequency shift, the second unambiguous Doppler component and the period of the first unit signal, and then the speed of the target can be determined based on the second Doppler ambiguity factor.

[0049] Specifically, the first frequency value can be obtained by summing half of the frequency difference with the difference frequency component, and the second frequency value can be obtained by subtracting half of the frequency difference from the difference frequency component. Then, the first and second frequency values ​​can be interpolated to obtain a second unambiguous Doppler component that is more in line with the actual situation.

[0050] In some optional embodiments, the rising and falling segments of each triangular wave are mirror-symmetrical, and the rising and falling segments can correspond to the rising and falling edges of the same chirp, or they can correspond to the rising edge of the previous chirp and the falling edge of the next chirp in two adjacent chirs. The specific method can be set according to the actual scenario and requirements. At the same time, the triangular wave can also be a falling segment and a rising segment in sequence, as long as the sequence of the two segments forming the triangular wave can achieve the purpose of de-velocity ambiguity after being processed by FFT. In the specific implementation process, the operation can be carried out with reference to the above-mentioned triangular wave with a rising segment and a falling segment in sequence in sequence. Since those skilled in the art can obtain the relevant specific implementation content by adaptively adjusting the content described in the embodiments of this application, it will not be elaborated here.

[0051] This application also provides a radar waveform. For any frame of transmitted signal, the radar waveform may include a triangular waveform segment. The triangular waveform segment includes a rising segment and a falling segment with the same period. The rising segment and the falling segment are mirror-symmetrical. The rising and falling segments of the same triangular wave correspond to the rising and falling edges of the same chirp, respectively, or the rising and falling segments of the same triangular wave correspond to the rising edge of the previous chirp and the falling edge of the next chirp in two adjacent chirs, respectively. For example, when applied to a TD MIMO radar system, one (or more) chirps with opposite slopes can be inserted in a transmission cycle to form the aforementioned triangular waveform segment with a chirp adjacent to the chirp. Alternatively, based on the effective edge of a conventional chirp, another symmetrical effective edge can be transmitted to form a triangular waveform segment composed of a single chirp. Therefore, the rising and falling segments of the same triangular waveform segment can be transmitted using the same transmitting antenna, or transmitted using the same antenna or different antennas.

[0052] This application also provides an integrated circuit, which may include a radio frequency (RF) module, an analog signal processing module, and a digital signal processing module connected in sequence; the RF module is used to generate an RF transmission signal and receive an RF echo signal; the analog signal processing module is used to down-convert the RF echo signal to obtain an intermediate frequency (IF) signal; and the digital signal processing module is used to perform analog-to-digital conversion on the IF signal to obtain a digital signal; wherein, the digital signal processing module further uses a velocity de-ambiguity method based on any embodiment of this application for velocity de-ambiguity de-ambiguity de-simplification.

[0053] In an optional embodiment, the integrated circuit described above can be a millimeter-wave radar chip. The types of digital functional modules in the integrated circuit can be determined according to actual needs. For example, in a millimeter-wave radar chip, the data processing module can be used for tasks such as range Vidoff transformation, velocity Vidoff transformation, constant false alarm rate detection, direction of arrival detection, and point cloud processing to acquire information such as the target's distance, angle, velocity, shape, size, surface roughness, and dielectric properties. Optionally, the integrated circuit can be an AiP (Antenna-In-Package) chip structure, an AoP (Antenna-On-Package) chip structure, or an AoC (Antenna-On-Chip) chip structure.

[0054] In an optional embodiment, when the integrated circuit is a chip structure, at least two chips can be cascaded to form a radar system with a larger antenna aperture and stronger processing capabilities. For the sake of simplicity, this will not be elaborated here, but it should be understood that all technologies that should be known by those skilled in the art based on the content described in this application should be included within the scope of this application.

[0055] In some optional embodiments, this application also provides a wireless device, comprising: a carrier; an integrated circuit as described in any of the above embodiments, wherein the integrated circuit may be disposed on the carrier; and an antenna disposed on the carrier, or integrated with the integrated circuit as a single device disposed on the carrier (i.e., the antenna may be an antenna disposed in an AiP, AoP, or AoC structure); wherein the integrated circuit is connected to the antenna (i.e., the sensing chip or integrated circuit does not have an integrated antenna, such as a conventional SoC), and is used to transmit and receive radio signals. The carrier may be a printed circuit board (PCB) (such as a development board, data acquisition board, or the motherboard of a device), and the first transmission line may be a PCB trace.

[0056] In some optional embodiments, this application also provides a terminal device, which may include: a device body; and a wireless device disposed on the device body as described in any of the above embodiments; wherein the wireless device can be used to implement functions such as target detection and / or wireless communication.

[0057] Specifically, based on the above embodiments, in one optional embodiment of this application, the wireless device may be disposed outside the device body or inside the device body. In other optional embodiments of this application, the wireless device may be partially disposed inside the device body and partially disposed outside the device body. This application does not limit the specific implementation; it may be determined according to the circumstances.

[0058] In an optional embodiment, the aforementioned device body can be a component or product applied in fields such as smart cities, smart homes, transportation, smart homes, consumer electronics, security monitoring, industrial automation, in-cabin detection (such as smart cockpits), medical devices, and healthcare. For example, the device body can be intelligent transportation equipment (such as automobiles, bicycles, motorcycles, ships, subways, trains, etc.), security equipment (such as cameras), liquid level / flow rate detection equipment, smart wearable devices (such as wristbands, glasses, etc.), smart home devices (such as robot vacuum cleaners, door locks, televisions, air conditioners, smart lights, etc.), various communication devices (such as mobile phones, tablets, etc.), as well as devices such as barriers, intelligent traffic lights, intelligent signs, traffic cameras, and various industrial robotic arms (or robots). It can also be various instruments for detecting vital signs parameters and various devices equipped with such instruments, such as in-cabin vital sign detection in automobiles, indoor personnel monitoring, smart medical devices, and consumer electronic devices.

[0059] It should be noted that wireless devices can transmit and receive radio signals to achieve functions such as target detection and / or communication, thereby providing the device body with target detection information and / or communication information, and thus assisting or even controlling the operation of the device body.

[0060] For example, when the aforementioned device is applied to an advanced driver assistance system (ADAS), wireless devices (such as millimeter-wave radar) used as vehicle sensors can assist the ADAS system in achieving application scenarios such as adaptive cruise control, automatic emergency braking (AEB), blind spot detection warning (BSD), lane change assist warning (LCA), rear cross traffic alert (RCTA), parking assist, rear vehicle warning, collision avoidance (such as door opening warning / collision avoidance), and pedestrian detection.

[0061] The following section will take the TD FMCW millimeter-wave radar as an example to elaborate on the specific technical solutions of this application:

[0062] Radar research began in the mid-to-late 1930s. Early development was slow due to limitations in components, but with advancements in integrated circuits in recent years, research into radar signal processing has become more active. The most fundamental problem of radar is detecting an object, tracking its position and velocity, and inferring its motion in three-dimensional space by measuring its position and radial velocity.

[0063] In fields such as autonomous vehicles and advanced driver assistance systems (ADAS), automotive millimeter-wave radar offers advantages such as small size, low cost, and all-weather adaptability, giving it a significant edge over sensors like lidar, ultrasonic radar, and cameras. The transmitted signal waveforms of automotive millimeter-wave radar primarily include continuous wave, pulsed continuous wave, and linear frequency modulated continuous wave (FMMC), with different waveforms suitable for different scenarios due to varying range and velocity resolutions. Among these, FMMCW is widely used in automotive millimeter-wave radar products because of its relatively simple signal generation and processing, and its ability to simultaneously achieve high range and velocity resolution.

[0064] FMCW signals decouple target range and velocity using two-dimensional FFT, enabling simultaneous detection of multiple targets. Their range and velocity resolution are inversely proportional to the sweep bandwidth and sweep interval. Unlike sensors such as lidar, microwave radar, and cameras, millimeter-wave radar is highly sensitive to target velocity information. For example, in a vehicle-mounted scenario, if the relative velocity between the target and the radar is large, exceeding the radar's maximum unambiguous velocity, the Doppler shift bandwidth caused by the target motion often exceeds the system's sweep repetition frequency. This means that velocity ambiguity caused by the Doppler shift is difficult to avoid, thus affecting the system's estimation of target velocity parameters.

[0065] Figure 1 A hardware block diagram of a radar system that can be used in embodiments of this application is shown. As shown, the radar system 100 includes a radio frequency chip 110, a transmitting antenna array 120, a receiving antenna array 130, and a main processing chip 140, wherein: the radio frequency chip 110 is configured to generate a detection signal and transmit it through the transmitting antenna array 120. The detection signal may be an FMCW electromagnetic wave signal.

[0066] The transmitting antenna array 120 is connected to the radio frequency chip 110 and may have at least two transmitting antennas 121 configured to transmit detection signals. The detection signals transmitted through different transmitting antennas 121 may have an initial phase difference, but are not limited to this.

[0067] As an example, the RF chip 110 includes components such as a millimeter-wave generator and a power amplifier to modulate and amplify the millimeter wave, thereby generating an RF signal. The RF chip 110 has at least two output terminals to provide probe signals to different transmitting antennas in the transmitting antenna array 120 at different time periods. In other examples, the RF chip 110 has at least two output terminals to provide probe signals with different phases to different transmitting antennas in the transmitting antenna array 120. For example, a phase shifter can be configured at the output of the power amplifier to shift the RF output signal provided by the power amplifier; in this case, the output of the power amplifier and the output of the phase shifter serve as the two output terminals of the RF chip 110.

[0068] The receiving antenna array 130 has multiple receiving antennas 131, configured to receive echo signals formed by the reflection of the detection signal by the target (i.e., the object being detected, the target object, hereinafter referred to as the target). Since the transmitted signals radiated by the multiple transmitting antennas can be reflected by the target object to form multiple echoes, the echo signal received by each receiving antenna includes multiple sets of echo signals corresponding to the multiple transmitting antennas respectively.

[0069] As an example, such as Figure 2 As shown, the spacing between two transmitting antennas 121 in the transmitting antenna array 120 is λ / 2, where λ is the wavelength of the probe signal (e.g., the center frequency). Four receiving antennas 131 are equally spaced, with the spacing between any two adjacent receiving antennas 131 being N·λ / 2, where N is optionally a natural number. In other examples, the number of transmitting antennas 121 is three or more, with multiple transmitting antennas 121 equally spaced, and the spacing between any two adjacent transmitting antennas 121 being λ / 2.

[0070] The main processing chip 140 is connected to the receiving antenna array 130 and the radio frequency chip 110, and is configured to process the echo signal obtained by the receiving antenna array 130 to obtain information such as the target's range, velocity, and angle. The processing of the echo signal may include mixing, sampling, two-dimensional FFT, target detection, and direction of arrival (DOA) estimation. Mixing refers to mixing the echo signal with its local oscillator signal to obtain an intermediate frequency (IF) signal. After sampling the IF signal, an FFT is performed in the range and velocity dimensions to obtain two-dimensional spectra of range and velocity. Then, constant false alarm rate (CFAR) detection can be used to determine the target's spectral peaks in the range and velocity dimensions. The frequencies corresponding to the spectral peaks in the range dimension include the difference frequency component and Doppler frequency component caused by the range, which are related to the target's range and velocity and can be used to calculate the distance between the target and the radar system. The Doppler frequency corresponding to the spectral peaks in the velocity dimension is related to the target's radial velocity relative to the radar system and can be used to calculate the target's ambiguous velocity and perform velocity deambiguation. Furthermore, the direction of arrival (DOA) of the target can be calculated using DOA estimation. In this paper, the Doppler frequency can also be referred to as Doppler frequency offset, Doppler frequency shift, etc.

[0071] Although Figure 1 The radar system 100 in this application is a MIMO radar system with multiple transmitting antennas and multiple receiving antennas, but a SIMO radar system with a single transmitting antenna and multiple receiving antennas can also be used as the radar system in this application embodiment.

[0072] It is important to note that Figure 1 The transmitting antenna 121 and receiving antenna 131 shown can also be connected to the radio frequency chip 110 simultaneously to form a radio frequency transceiver chip, while the main processing chip 140 is only used for signal processing, thus forming a radar signal transceiver processing system. Meanwhile, Figure 1 The functional units in the RF chip 110 and main processing chip 140 shown can also be integrated into a single SoC chip, meaning that RF signal transmission, reception, and processing can be achieved with a single chip. In some optional embodiments, the transmitting antenna and receiving antenna can also be integrated with the SoC chip to form an AiP chip or AoC chip structure. Therefore, the speed deambiguation method and corresponding apparatus described in this application can be applied to the aforementioned radar systems based on different chips, as well as radar systems based on a single chip.

[0073] Figure 3 This is a functional block diagram of the radar system that can be used in this embodiment. For example... Figure 3As shown, the radar system may include a transmitting antenna 11, a power amplifier 21, a signal generator 23, a receiving antenna 13, a low-noise amplifier 31, a mixer 33, an analog-to-digital converter (ADC) module 41, a two-dimensional FFT module 51, and a target detection module 53.

[0074] Signal generator 23 can be a millimeter-wave generator implemented with an oscillator. The probe signal generated by signal generator 23 is amplified by power amplifier 21 and then transmitted through one or more transmitting antennas 11. In one example, the probe signal is an FMCW signal with a sawtooth waveform, such as... Figure 4 As shown. Each frame of signal includes multiple chirps, each chirp signal including an up-modulation band (also called the rising band or rising edge), a down-modulation band (also called the falling band or falling edge), and a frequency hold band. The period of the chirp signal is Tc. The signal transmission channel of the radar system consists of devices such as a signal generator 23 and a power amplifier 21.

[0075] The detection signal is reflected and / or refracted by the target to form an echo signal. The receiving antenna 13 amplifies the received echo signal through a low-noise amplifier 31, and then mixes it with the corresponding local oscillator signal in a mixer 33 to obtain an intermediate frequency signal. There are usually multiple receiving antennas 13. The signal receiving channel of the radar system is composed of components such as the low-noise amplifier 31 and the mixer 33. The signal transmitting channel and the signal receiving channel are collectively referred to as the signal transmission and reception channel.

[0076] The intermediate frequency signal is sampled by the analog-to-digital converter (ADC) 41 to obtain a digital signal. A two-dimensional FFT module then performs range-dimensional FFT and velocity-dimensional FFT on the digital signal. The range-dimensional FFT is performed on the sampling points obtained within each chirp, while the velocity-dimensional FFT is performed on the sampling points obtained across different chirs. The two-dimensional spectrum of the range and velocity of the digital signal obtained after the two-dimensional FFT is used as input to the target detection module.

[0077] Target detection 53 is configured to detect the target's distance, velocity, and direction of arrival (DOA) based on the two-dimensional spectrum. The CFAR detection unit 531 can first determine the target's spectral peaks in the range and velocity dimensions. The ranging unit 533 calculates the target's distance based on the relationship between the frequency corresponding to the spectral peak in the range dimension of the two-dimensional spectrum and the target's distance, and can further correct this distance based on the Doppler frequency in the velocity dimension. The velocity measurement unit 535 calculates the target's velocity based on the relationship between the Doppler frequency corresponding to the spectral peak in the velocity dimension of the two-dimensional spectrum and the target's velocity, and can also calculate the target's ambiguous velocity and perform velocity deambiguation. The DOA estimation unit 537 can calculate the target's DOA using methods such as maximum likelihood estimation. In the case of multiple distinguishable targets, targets at different distances have different spectral peak positions in the range dimension, and targets at different velocities have different spectral peak positions in the velocity dimension.

[0078] It should be noted that actual radar systems can contain more than [number of modules]. Figure 3 The functional modules in the above-mentioned modules can be modified by deleting some modules or replacing some modules with other functional modules. For example, a de-phase winding module can be added before the two-dimensional FFT, and clustering, target tracking, and target recognition units can be added to the target detection module.

[0079] The aforementioned power amplifier 21, signal generator 23, low-noise amplifier 31, and mixer 33 can be set in... Figure 1 In the RF chip shown, the analog-to-digital conversion module 41, the two-dimensional FFT module 51, and the target detection module 53 described above can be set in... Figure 1 The main processing chip shown is used, but is not limited to this.

[0080] To obtain target velocity information, radar systems typically transmit a series of chirps frame by frame. The phase difference of these chirps is then used to measure the target velocity in the target field. Specifically, a range FFT is performed on the sampling points corresponding to each chirp, and the output is stored in a matrix in consecutive rows, containing information in both range and velocity dimensions. After receiving and processing all individual chirps in a frame, the processor begins performing a velocity-dimensional FFT (Doppler FFT) on the chirp sequence. The joint operation of range FFT (row-by-row) and Doppler FFT (column-by-column) can be viewed as a two-dimensional FFT for each sampling point in each frame. The two-dimensional FFT can simultaneously resolve the target's range and velocity; that is, the spectral peak positions of the spectrum obtained by the two-dimensional FFT correspond to the target's range and velocity relative to the radar.

[0081] The detection signals emitted by FMCW-based radar systems generally use Figure 4The sawtooth waveform shown is composed of multiple chirps per frame. Based on the principle of radar velocity measurement, the maximum unambiguous velocity v that a radar system can detect is... max The cycle length T of Chirp c It is inversely proportional and can be calculated based on the radar system parameters. If the target's velocity relative to the radar is greater than the maximum unambiguous velocity v... max If this velocity is not clear, it will correspond to the same Doppler frequency as a relatively low velocity, resulting in indistinguishability. In this case, it is necessary to use methods to solve for the velocity value exceeding the maximum unambiguous velocity to obtain the unambiguous velocity, i.e., velocity deambiguation. The unambiguous velocity of the target (i.e., the true velocity) is v = v0 + q·v max v0 is the fuzzy velocity, and q is the fuzziness factor. Once v0 and q are determined, the unfuzzy velocity v can be calculated. q can be 0 or an integer, such as -2, -1, 0, 1, 2, etc.

[0082] In one embodiment, to achieve velocity deambiguity, the radar system transmits two frames with different periods, such as... Figure 5 Frames A and B in the image. Because the chirp period length is different in frames A and B, i.e., T... c1 ≠T c2 Therefore, when the target's velocity exceeds the maximum unambiguous velocity of one or two frames, the positions of the corresponding Doppler frequency points after demodulation in frames A and B are different. Based on the relative positions of these two frequency points, the velocity value exceeding the maximum unambiguous velocity corresponding to those two frames can be determined. However, this method uses two different frames, making multi-target matching difficult.

[0083] In another embodiment, to achieve velocity deambiguity, the radar system transmits subframes composed of chirps with different period durations, such as... Figure 6 As shown. Compared to a regular frame, this frame adds a delay 'a' after the 0th, 2nd, 4th... chirps (even-numbered chirps), while the chirp period of the 1st, 3rd, 5th... chirps (odd-numbered chirps) is T. c2 This makes the period duration T of even-numbered chirps... c1 =T c2 +a. Other parameters of chirp remain unchanged. Thus, the Doppler frequency components of the velocity obtained from odd-numbered and even-numbered chirp are the same, but have different phase differences. These phase differences are related to the ambiguity factor, and the ambiguity factor can be solved based on this phase difference, thereby obtaining the unambiguous velocity of the target.

[0084] This method utilizes phase, which requires a high signal-to-noise ratio (SNR). When targets are close together, the phases interfere with each other, resulting in a relatively high probability of error. Furthermore, the waveform transmitted by this radar system for velocity unambiguity reduces the maximum unambiguous velocity.

[0085] To improve the reliability of velocity deambiguation without increasing the difficulty of multi-target matching, some embodiments of this application provide a velocity deambiguation method applicable to frequency-modulated continuous wave (FMCW) radar systems. This method transmits FMCW signals via an antenna, and each frame of the signal may include a first chirp signal constituting the rising segment of a triangular wave. e and the second chirp signal chirp constituting the falling segment of the triangular wave. o ; Receive chirp e and chirp o The echo signals are mixed, sampled, and subjected to two-dimensional FFT to determine the frequency difference corresponding to the same target (peak) at range gates Se and So (i.e., in the range dimension), where Se is the chirp. e The sequence is processed by a distance-dimensional FFT to obtain the data, so is chirp. o The sequence is subjected to a distance-dimensional FFT to obtain data; the unambiguous velocity of each target is determined based on the frequency difference.

[0086] Specifically, such as Figure 7 As shown, the method may include:

[0087] Step 1: Transmit an FMCW signal via an antenna (such as at least one transmitting antenna). Each frame of the signal may include a first unit signal constituting the rising segment of a triangular wave and a second unit signal constituting the falling segment of the triangular wave.

[0088] In this embodiment, the first unit signal is the first chirp signal. e The second unit signal is the second chirp signal. o .

[0089] Step 2: Perform range-dimensional FFT on the first unit signal sequence and the second unit signal sequence in the echo signal respectively to obtain the frequency difference of the same target in the range dimension;

[0090] In one example of this embodiment, chirp is received in this step. e and chirp o The echo signals were mixed, sampled, and subjected to two-dimensional FFT to determine S. e and S o The frequency difference corresponding to the same target in the range dimension; where Se is the chirp in the echo signal. eSequence (i.e., chirp) e The echo signal is obtained by performing a distance-dimensional FFT on the data, and So is the chirp in the echo signal. o Sequence (i.e., chirp) o The data obtained by performing a distance-dimensional FFT on the echo signal.

[0091] Optionally, in one example, frequency difference can refer to the absolute value of the difference between two frequencies, and in another example, frequency difference can also refer to the difference between two frequencies.

[0092] Step 3: Determine the unambiguous velocity of the target based on the frequency difference.

[0093] The velocity deambiguation method in this embodiment emits two types of chirps that constitute the rising and falling segments of a triangular wave, which does not cause difficulties in multi-target matching.

[0094] In an exemplary embodiment of this application, the FMCW signal transmitted by the radar system is a triangular wave signal, that is, its waveform is a triangular wave. For example... Figure 8 As shown in the figure. In this embodiment, the chirps are divided into two groups. The chirps with even numbers, such as chirp0, chirp2, chirp4, etc., form one group, which constitutes the rising segment of the triangular wave, referred to in this text as the first chirp signal. e The chirps with odd numbers, such as chirp1, chirp3, chirp5, etc., form a group that constitutes the descending segment of the triangular wave, referred to in the text as the first chirp signal. o A chirp e A chirp o The period is T. r The period of the triangular wave can be T. c T c =2T r The rising and falling segments of the triangular wave can have the same parameters, such as the absolute value of the slope, the period duration, and the bandwidth, except that one is an up-modulation band and the other is a down-modulation band. This avoids difficulties in multi-target matching.

[0095] In an exemplary embodiment of this application, the FMCW signal transmitted by the radar system has a combined waveform, which includes interleaved triangular waveform segments and sawtooth waveform segments, such as... Figure 9 As shown. This embodiment utilizes the triangular band to achieve velocity deblurring, while the sawtooth waveform segment, including the rising segment of the triangular band, can be used to achieve other target detection.

[0096] In an exemplary embodiment of this application, for any of the said triangular waves, the rising segment and the falling segment are mirror-symmetrical.

[0097] In an exemplary embodiment of this application, the rising segment and falling segment of the same triangular wave correspond to the rising edge and falling edge of the same chirp, respectively; or, the rising segment and falling segment of the same triangular wave correspond to the rising edge of the previous chirp and the falling edge of the next chirp, respectively, of two adjacent chirs.

[0098] In an exemplary embodiment of this application, the radar system is a MIMO radar system; the waveform transmitted in one transmission cycle of the MIMO radar system includes at least one of the triangular waves.

[0099] According to the principle of radar velocity measurement, the unambiguous velocity of the target is v = v0 + q·V max Maximum unambiguous speed V max =λ / (4NT) c ); where T c λ is the period duration of the signal (such as a triangular wave), N is the number of transmitting antennas in the radar system, and λ is the wavelength of the transmitted FMCW signal; v0 is the ambiguity velocity of the target, and q is the ambiguity factor; v0 can be obtained by solving the velocity dimension FFT in the existing way. If the ambiguity factor q can be obtained, the unambiguous velocity v of the target can be calculated.

[0100] One embodiment of this application uses the unambiguous Doppler frequency f corresponding to the unambiguous velocity v of the target. d,unamb And the fuzzy Doppler frequency f corresponding to the fuzzy velocity v0 of the target. d To solve for the fuzzy multiple q, the principle is as follows:

[0101] According to the Doppler principle, we have:

[0102] Unambiguous Doppler frequency f d,unamb =2v / λ=2(v0+q·V) max ) / λ=2v0 / λ+2q·V max / λ; This unambiguous Doppler frequency can also be called the unambiguous Doppler component, or the unambiguous Doppler frequency component.

[0103] The blurred Doppler frequency f d =2v0 / λ;

[0104] The meanings of each parameter are as described above. This is because the sampling rate of an ADC is generally much higher than 1 / 2T. r The above calculation method is reasonable.

[0105] V max =λ / (4NT) c Substitute the values ​​into the formula for calculating the unambiguous Doppler frequency, and replace 2v0 / λ with f. d ,have:

[0106] f d,unamb =f d +q / (2NT c (1)

[0107] Therefore, f was determined. d,unamb f d Then, according to formula (1), the blur factor q (q can be positive, 0, or negative) can be solved, and then the unblurred velocity of the target can be calculated. The v0 calculated from the velocity-dimensional FFT result has high accuracy, and f... d It can be obtained by performing a velocity-dimensional FFT on the chirp sequence in the echo signal, and f d,unamb Then it can be done through S e and S o The frequency difference corresponding to the same target is obtained in the distance dimension.

[0108] See Figure 10 In a scenario with a moving target, the frequency f of the intermediate frequency signal (also known as the difference frequency signal) corresponding to the rising segment of the triangular wave is... b+ =f b -f d The falling segment of the triangular wave corresponds to the intermediate frequency signal frequency f. b- =f b +f d ; where f b Let f be the frequency of the intermediate frequency signal when the radar and the target are relatively stationary, and this frequency is proportional to the distance to the target. d The Doppler frequency introduced by the target's motion is proportional to the target's velocity. Figure 8 Taking the transmitted waveform shown as an example, the digital signals obtained after sampling the first intermediate frequency signal corresponding to the rising segment of the triangular wave and the second intermediate frequency signal corresponding to the falling segment of the triangular wave can be represented by trigonometric functions as follows:

[0109] x e [n,l]=cos(2π(f b -f d,unamb )nTs+4πf d T r l) (2)

[0110] x o [n,l]=cos(2π(f b +f d,unamb )nTs+4πf d T r l) (3)

[0111] Where, x e [n,l] represents the sampling points (or simply samples) of the digital signal obtained after sampling the first intermediate frequency signal, x o[n,l] represents the sample points of the digital signal obtained after sampling the second intermediate frequency signal, where n is the index of the sample point in the chirp and l is the index of the chirp where the sample point is located.

[0112] Among them, f b f is the frequency of the intermediate frequency signal when the radar and the target are relatively stationary, and is proportional to the distance to the target. d,unamb For unambiguous Doppler components, T r For a chirp e The period, Ts is the sampling period, f d The Doppler frequency is ambiguous.

[0113] In formula (2), (f) b -f d,unamb That is, the frequency of the first intermediate frequency signal corresponding to the rising segment of the triangular wave in the distance dimension (equivalent to...). Figure 10 f in b+ ); while in formula (3) (f b +f d,unamb That is, the frequency of the second intermediate frequency signal corresponding to the falling segment of the triangular wave in the distance dimension (equivalent to...). Figure 10 f in b- Therefore, based on the frequency f of the same target in the distance dimension of the two intermediate frequency signals... e and f o The difference can be used to obtain f d,unamb Expressed as a formula: f d,unamb =|f e -f o | / 2. Therefore, this frequency difference |f e -f o | equals the unambiguous Doppler efficiency f resulting from the motion of the target object. d,unamb Twice as much.

[0114] The unambiguous Doppler frequency can be calculated by the frequency difference in the distance dimension. Then, the unambiguous velocity can be calculated by using the conversion relationship between the unambiguous Doppler frequency and the unambiguous velocity. However, the accuracy of the unambiguous Doppler frequency calculated in the distance dimension is not high, while the accuracy of the ambiguous Doppler frequency calculated in the velocity dimension is higher. Therefore, in this embodiment, the ambiguity factor q is first solved based on the relationship between the maximum unambiguous velocity, the unambiguous Doppler frequency, and the ambiguous Doppler frequency, and then the accurate unambiguous velocity of the target is obtained.

[0115] In an exemplary embodiment of this application, performing range-dimensional FFT on the first and second unit signal sequences in the echo signal to obtain the frequency difference of the same target in the range dimension includes:

[0116] From the two-dimensional spectrum obtained after sampling and two-dimensional FFT of the first unit signal sequence in the echo signal, the spectral peak positions in the distance dimension are extracted, and S is calculated based on the spectral peak positions. e The frequency f corresponding to the target in the distance dimension e ;

[0117] From the two-dimensional spectrum obtained after sampling and two-dimensional FFT of the second unit signal sequence in the echo signal, the spectral peak positions in the distance dimension are extracted, and S is calculated based on the spectral peak positions. o The frequency f corresponding to the target in the distance dimension o ;

[0118] |f e -f o |f represents the frequency difference of the target in the distance dimension. e -f o |is f e and f o The absolute value of the difference.

[0119] The position of a spectral peak (also known as the location of the target on the spectrum) can be represented by the indices n, l of the sampling points where the spectral peak is located. For example... Figure 11 The diagram shows the sampling point matrix obtained after performing a 2DFTT on an intermediate frequency signal. The filled block labeled 10 represents a spectral peak with an index n of 10 in the distance dimension and an index l of 15 in the velocity dimension. The filled block labeled 20 represents another spectral peak with an index n of 10 in the distance dimension and an index l of 13 in the velocity dimension. The frequency corresponding to the spectral peak in the distance dimension can be calculated based on index n, and this frequency can be used to calculate the target's distance. In this embodiment, it is also used to assist in calculating the unambiguous velocity of the target. The frequency corresponding to the spectral peak in the velocity dimension can be calculated based on index l (which can be used as the ambiguous Doppler frequency), and this frequency can be used to calculate the ambiguous velocity of the target. The specific conversion method between the spectral peak position and the above frequency is not described in this embodiment.

[0120] The aforementioned "same target" can be any one of multiple targets, meaning that velocity defuzzification can be performed on each of the multiple targets that need to be measured.

[0121] In an exemplary embodiment of this application, determining the velocity of the target based on the frequency difference includes:

[0122] A velocity-dimensional FFT is performed on the first and second unit signal sequences in the echo signal to obtain the Doppler frequency shift of the target.

[0123] The first unambiguous Doppler component is determined based on the frequency difference;

[0124] The first Doppler ambiguity factor is determined based on the Doppler frequency shift, the first unambiguous Doppler component, and the period of the first unit signal; and

[0125] The velocity of the target is determined based on the first Doppler ambiguity factor.

[0126] This embodiment performs velocity-dimensional FFT on the first and second unit signal sequences in the echo signal to obtain the Doppler frequency shift of the target. If the first Doppler frequency shift of the target obtained by performing velocity-dimensional FFT on the first unit signal sequence is the same as the second Doppler frequency shift of the target obtained by performing velocity-dimensional FFT on the second unit signal sequence, then this same Doppler frequency shift is used as the Doppler frequency shift of the target. If the obtained first Doppler frequency shift and second Doppler frequency shift are different, then the mean or weighted average of the first and second Doppler frequency shifts can be used as the Doppler frequency shift of the target. In other embodiments, either the first or second Doppler frequency shift can be used as the Doppler frequency shift of the target.

[0127] In one example of this embodiment, determining the first Doppler ambiguity factor based on the Doppler frequency shift, the first unambiguous Doppler component, and the period of the first unit signal can be done in the following way: determining f d +q / (2NT c ) and f d,unamb The closest blur factor q is also the first Doppler blur factor mentioned above, f d,unamb For unambiguous Doppler frequencies, 2f d,unamb Equal to the frequency difference, T c Let q be the period of the triangular wave, q be an integer, and N be the number of transmitting antennas in the radar system.

[0128] Usually f d,unamb Much less than 1 / T S f d,unamb It may be within one FFT bin, therefore f d,unamb By f b +f d,unamb and f b -f d,unamb Interpolation is used to obtain a more accurate value. Specifically, this can be achieved by searching within the range of values ​​for q to find the value of f. d +q / (2NT c ) and f d,unambThe closest possible value is used. The range of the ambiguity factor q can be preset according to the possible movement speed of the target in the actual scene. In one example, the range is {-2,-1,0,1,2}, but it can also be a set of more or smaller values. Positive and negative q represent the two directions of movement of the target, namely, moving towards or away from the radar.

[0129] In one example of this embodiment, determining the target's velocity based on the first Doppler ambiguity factor includes: calculating the target's unambiguous velocity v = v0 + qV. max v0 is the blurred velocity of the target, V max The maximum unambiguous speed is denoted as .

[0130] In an exemplary embodiment of this application, determining the first unambiguous Doppler component based on the frequency difference includes: dividing the frequency difference by 2 to obtain the first unambiguous Doppler component. This can be expressed as: f d,unamb =|f e -f o | / 2.

[0131] In an exemplary embodiment of this application, determining the velocity of the target based on the frequency difference includes:

[0132] Velocity-dimensional FFT is performed on the first and second unit signal sequences in the echo signal to obtain the Doppler frequency shift and difference frequency components of the target.

[0133] The second unambiguous Doppler component is determined based on the frequency difference and the difference frequency component;

[0134] The second Doppler ambiguity factor is determined based on the Doppler frequency shift, the second unambiguous Doppler component, and the period of the first unit signal; and

[0135] The velocity of the target is determined based on the second Doppler ambiguity factor.

[0136] In one example of this embodiment, determining the second unambiguous Doppler component based on the frequency difference and the difference frequency component includes: determining the second unambiguous Doppler component by interpolation based on the frequency difference and the difference frequency component. An exemplary interpolation method is: obtaining the difference frequency component (the frequency of the intermediate frequency signal); determining the second unambiguous Doppler component based on the frequency difference and the difference frequency component by interpolation includes: using the sum of half the frequency difference and the difference frequency component as a first frequency value; using the difference frequency component minus half the frequency difference as a second frequency value; and interpolating the first frequency value and the second frequency value to obtain the second unambiguous Doppler component.

[0137] One embodiment of this application also provides a velocity deambiguation device in a radar system, such as... Figure 12 As shown, it includes a memory 50 and a processor 60. The memory 50 stores a computer program, and the processor 60, when executing the computer program, can implement the velocity deambiguation method based on frequency-modulated continuous wave described in any embodiment of this application. This velocity deambiguation device can be used... Figure 1 The corresponding software and hardware implementations are shown in the main processing chip and the transmitter chip.

[0138] The processor in the embodiments can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), a microprocessor, etc., or other conventional processors; the processor can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), discrete logic or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components; or a combination of the above devices. That is, the processor in the above embodiments can be any processing device or combination of devices that implements the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. If the embodiments of this application are implemented in part by software, then instructions for software can be stored in a suitable non-volatile computer-readable storage medium, and one or more processors can be used to execute the instructions in hardware to implement the methods of the embodiments of this application.

[0139] One embodiment of this application also provides a non-transient computer-readable storage medium storing a computer program that, when executed by a processor, can implement the speed defuzzification method described in any embodiment of this application.

[0140] One embodiment of this application also provides a radar waveform, wherein for any frame of transmitted signal, the radar waveform includes a triangular waveform segment; the triangular waveform segment includes a rising segment and a falling segment with the same period; wherein the rising segment and the falling segment are mirror-symmetrical. An example of this radar waveform could be... Figure 8 , Figure 9 The waveform shown.

[0141] In one example of this embodiment, the rising segment and falling segment of the same triangular wave correspond to the rising edge and falling edge of the same chirp, respectively; or, the rising segment and falling segment of the same triangular wave correspond to the rising edge of the previous chirp and the falling edge of the next chirp in two adjacent chirs, respectively.

[0142] In one example of this embodiment, the radar waveform is applied to a TD MIMO radar system; the waveform transmitted in one transmission cycle of the TD MIMO radar system includes at least one of the triangular waves.

[0143] In one example of this embodiment, the rising and falling segments of the same triangular waveform segment are transmitted using the same transmitting antenna.

[0144] In one example of this embodiment, velocity deambiguation can be performed based on the rising and falling segments of the triangular waveform segment. For example, the velocity deambiguation method described in any embodiment of this application can be used to perform velocity deambiguation in a radar system based on the rising and falling segments of the triangular waveform segment.

[0145] One embodiment of this application also provides an integrated circuit, such as... Figure 13 As shown, the integrated circuit includes a radio frequency module 2011, an analog signal processing module 2012, and a digital signal processing module 2013 connected in sequence, wherein:

[0146] The radio frequency module 2011 is used to generate radio frequency transmission signals and receive radio frequency echo signals;

[0147] The analog signal processing module 2012 is used to down-frequency the radio frequency echo signal to obtain an intermediate frequency signal; and

[0148] The digital signal processing module 2013 is used to perform analog-to-digital conversion on the intermediate frequency signal to obtain a digital signal; wherein, the digital signal processing module also performs speed deblurring using the speed deblurring method based on any embodiment of this application.

[0149] This application also provides a wireless device, such as Figure 14 As shown, it includes: a carrier 4; an integrated circuit 5 according to any embodiment of this disclosure, disposed on the carrier 4; an antenna 6, disposed on the carrier 4, or the antenna 6 and the integrated circuit 5 are integrated into a single device disposed on the carrier 4; wherein, the integrated circuit 5 is connected to the antenna 6 and is used to transmit the radio frequency transmission signal and / or receive the radio frequency echo signal.

[0150] This application also provides a terminal device, including: a device body; and a wireless device disposed on the device body as described in any embodiment of this disclosure; wherein the wireless device is used for target detection and / or communication to provide reference information to the operation of the device body.

[0151] It will be understood by those skilled in the art that all or some of the steps, systems, or apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software may be distributed on a computer-readable medium, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

Claims

1. A velocity deambiguation method applied to a frequency-modulated continuous wave (FMCW) radar system, wherein each frame of signal transmitted by the radar system includes a first unit signal constituting the rising segment of a triangular wave and a second unit signal constituting the falling segment of the triangular wave, wherein the first unit signal and the second unit signal have the same period; the method includes: Range-dimensional FFT is performed on the first and second unit signal sequences in the echo signal to obtain the frequency difference of the same target in the range dimension. The speed of the target is determined based on the frequency difference; The step of determining the target's velocity based on the frequency difference includes: A velocity-dimensional FFT is performed on the first and second unit signal sequences in the echo signal to obtain the Doppler frequency shift of the target. The first unambiguous Doppler component is determined based on the frequency difference; The first Doppler ambiguity factor is determined based on the Doppler frequency shift, the first unambiguous Doppler component, and the period of the first unit signal; and The velocity of the target is determined based on the first Doppler ambiguity factor; Alternatively, determining the target's velocity based on the frequency difference includes: Velocity-dimensional FFT is performed on the first and second unit signal sequences in the echo signal to obtain the Doppler frequency shift and difference frequency components of the target. The second unambiguous Doppler component is determined based on the frequency difference and the difference frequency component; The second Doppler ambiguity factor is determined based on the Doppler frequency shift, the second unambiguous Doppler component, and the period of the first unit signal; and The velocity of the target is determined based on the second Doppler ambiguity factor.

2. The method as described in claim 1, characterized in that, Determining the first unambiguous Doppler component based on the frequency difference includes: Divide the frequency difference by 2 to obtain the first unambiguous Doppler component.

3. The method as described in claim 2, characterized in that, Determining the second unambiguous Doppler component based on the frequency difference and the difference frequency component includes: The second unambiguous Doppler component is determined by interpolation based on the frequency difference and the difference frequency component.

4. The method as described in claim 3, characterized in that, It also includes acquiring the difference frequency component; the step of determining the second unambiguous Doppler component based on the frequency difference and the difference frequency component through interpolation includes: The sum of half of the frequency difference and the difference frequency component is taken as the first frequency value; The difference between the difference frequency component and half of the frequency difference is taken as the second frequency value; and The second unambiguous Doppler component is obtained by interpolating the first frequency value and the second frequency value.

5. The method according to any one of claims 1-4, characterized in that, For any of the aforementioned triangular waves, the rising segment and the falling segment are mirror-symmetric.

6. The method as described in claim 5, characterized in that, The rising and falling segments of the same triangular wave correspond to the rising and falling edges of the same chirp, respectively.

7. The method as described in claim 6, characterized in that, The rising and falling segments of the same triangular wave correspond to the rising edge of the previous chirp and the falling edge of the next chirp in two adjacent chirps, respectively.

8. The method as described in claim 5, characterized in that, The radar system is a MIMO radar system; The waveform transmitted in one transmission cycle of a MIMO radar system includes at least one of the aforementioned triangular waves.

9. A velocity deambiguation device in a radar system, characterized in that, The device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the velocity deambiguation method based on frequency-modulated continuous waves as described in any one of claims 1 to 8.

10. A non-transient computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, characterized in that, when the computer program is executed by a processor, it implements the speed defuzzification method according to any one of claims 1 to 8.

11. A method for designing radar waveforms, characterized in that, Configured to implement the velocity deambiguation method as described in claim 1, for any frame of transmitted signal, the radar waveform includes a triangular waveform segment; the triangular waveform segment includes a rising segment and a falling segment with the same period; wherein the rising segment and the falling segment are mirror-symmetric.

12. The radar waveform design method as described in claim 11, characterized in that, The rising and falling segments of the same triangular wave correspond to the rising and falling edges of the same chirp, respectively.

13. The radar waveform design method as described in claim 11, characterized in that, The rising and falling segments of the same triangular wave correspond to the rising edge of the previous chirp and the falling edge of the next chirp in two adjacent chirps, respectively.

14. The radar waveform design method as described in claim 11, characterized in that, It is applied to a radar system, wherein the radar system is a TD MIMO radar system; The waveform transmitted in one transmission cycle of the TD MIMO radar system includes at least one of the triangular waves.

15. The radar waveform design method as described in claim 14, characterized in that, The rising and falling segments of the same triangular waveform segment are transmitted using the same transmitting antenna.

16. The radar waveform design method according to any one of claims 11-15, characterized in that, Velocity defuzzification can be performed based on the rising and falling segments of the triangular waveform.

17. An integrated circuit, characterized in that, It includes a radio frequency module, an analog signal processing module, and a digital signal processing module connected in sequence; The radio frequency module is used to generate radio frequency transmission signals and receive radio frequency echo signals; The analog signal processing module is used to down-frequency the radio frequency echo signal to obtain an intermediate frequency signal; and The digital signal processing module is used to perform analog-to-digital conversion on the intermediate frequency signal to obtain a digital signal; The digital signal processing module further performs speed deblurring using the method described in any one of claims 1-8.

18. The integrated circuit according to claim 17, characterized in that, The integrated circuit is a millimeter-wave chip.

19. A wireless device, characterized in that, include: Carrier; The integrated circuit as described in claim 17 or 18 is disposed on the carrier. An antenna is disposed on the carrier, or the antenna and the integrated circuit are integrated into a single device and disposed on the carrier. The integrated circuit is connected to the antenna and is used to transmit the radio frequency transmission signal and / or receive the radio frequency echo signal.

20. A terminal device, characterized in that, include: Equipment body; as well as The wireless device as described in claim 19 is disposed on the device body; The wireless device is used for target detection and / or communication to provide reference information for the operation of the device body.

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