A MIMO radar and a signal processing method

Abstract

This invention provides a MIMO radar and a signal processing method, applicable to the field of radar technology. The MIMO radar includes: a transmit gating switch module, a signal generation module, multiple transmit antennas, a receive gating switch module, a signal receiving module, a radar signal processing module, and multiple receive antennas. The multiple receive antennas share a single receive link and their operating timings do not overlap. The signal generation module generates radar signals; the transmit gating switch module sequentially activates each transmit antenna; the receive gating switch module sequentially activates each receive antenna according to a specified switching mode when each transmit antenna is activated; the signal receiving module acquires the radar echo signals received by the receive antennas; and the radar signal processing module performs phase difference compensation on the radar echo signals to obtain the target result. Compared with existing technologies, the solution provided by this invention can compensate for the phase difference caused by switching while achieving dual switching of RX and TX, thereby improving radar performance.

Description

Technical Field

[0001] This invention relates to the field of radar technology, and in particular to a MIMO radar and a signal processing method. Background Technology

[0002] Currently, with the continuous development of radar technology, radar is being widely applied to more and more technical fields, such as road monitoring, weather warning, crustal detection, and motion detection.

[0003] In related technologies, in order to accurately obtain task results, such as the distance, speed, and angle of the object detected by the radar, and to effectively reduce the cost and complexity of the radar, a single-transmitter, multi-receiver radar is usually used to perform various tasks.

[0004] The aforementioned single-transmitter multiple-receiver radar includes a single transmit antenna (TX) and multiple receive antennas (RX). Furthermore, this radar can perform various tasks using a scheme of randomly switching receive channels. Specifically: First, the TX transmits a chirp signal. Then, during the continuous transmission duration of this chirp signal, a random sequence generator generates a random sequence. Following this random sequence, multiple RXs are switched using gating switches, sequentially activating each RX. Each RX has the same activation time and is activated only once. The activated RX receives the radar echo signal from the chirp signal generated by the TX. After all RXs have been activated, the cycle repeats. Finally, all received radar echo signals are mixed, and the task results are calculated.

[0005] However, in the aforementioned related technologies, although the coupling between each RX is reduced by randomly switching each RX, the phase difference between each RX when receiving radar echo signals will result in a loss of signal-to-noise ratio in the obtained task results, thus leading to poor accuracy of the task results.

[0006] Therefore, how to compensate for the phase difference caused by the switching of RX and TX while realizing dual switching of RX and TX, so as to reduce the signal-to-noise ratio loss of the obtained mission results and thus improve the performance of the radar, has become an urgent problem to be solved. Summary of the Invention

[0007] The purpose of this invention is to provide a MIMO radar and a signal processing method to compensate for the phase difference caused by the switching of RX and TX, thereby reducing the signal-to-noise ratio loss of the obtained task results and improving the performance of the radar, based on the dual switching of RX and TX.

[0008] The specific technical solution is as follows:

[0009] In a first aspect, embodiments of the present invention provide a MIMO radar, the MIMO radar comprising: a transmit gating switch module, a signal generation module, multiple transmit antennas, a receive gating switch module, a signal receiving module, a radar signal processing module, and multiple receive antennas, wherein the multiple receive antennas share a single receive link and their operating timings do not overlap;

[0010] The signal generation module is used to generate the radar signal emitted by the MIMO radar;

[0011] The transmit gating switch module is used to sequentially switch the plurality of transmit antennas. When switched to a transmit antenna, the transmit antenna is turned on so that the transmit antenna transmits the radar signal.

[0012] The receive gating switch module is used to sequentially switch the plurality of receive antennas according to a specified switching mode among a preset plurality of switching modes when each transmit antenna is turned on, and when switching to a receive antenna, turn on that receive antenna so that the receive antenna receives the radar echo signal of the radar signal in the specified switching mode; wherein, the plurality of switching modes include: a first switching mode that controls each receive antenna to receive a radar echo signal of a complete radar signal, and a second switching mode that controls each receive antenna to receive a radar echo signal of a portion of a complete radar signal;

[0013] The signal receiving module is used to acquire the radar echo signal received by each receiving antenna;

[0014] The radar signal processing module is configured to, if the specified switching mode is the first switching mode, perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas after switching the multiple transmitting antennas, to obtain the target result; if the specified switching mode is the second switching mode, perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas and the second type of phase difference caused by switching the multiple receiving antennas after switching the multiple transmitting antennas, to obtain the target result.

[0015] Optionally, in one specific implementation, the first switching mode includes:

[0016] When each transmitting antenna is turned on, each receiving antenna sequentially receives the radar echo signal of a complete radar signal transmitted by that transmitting antenna. After all the receiving antennas have received the radar echo signal, the next transmitting antenna of that transmitting antenna transmits the radar signal, and so on in a cycle.

[0017] Optionally, in one specific implementation, the radar signal processing module is specifically used for:

[0018] Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the first processing result;

[0019] Based on the slow time period dimension, the first processing result is subjected to Fourier transform to obtain the second processing result;

[0020] Based on the first type of phase difference, phase difference compensation is performed on the second processing result to obtain the target result.

[0021] Optionally, in one specific implementation, the second switching mode includes:

[0022] When each transmitting antenna is turned on, during the duration of transmitting a complete radar signal, the plurality of receiving antennas are turned on sequentially and receive radar echo signals of a portion of the radar signal transmitted by the transmitting antenna during the turn-on duration. The turn-on duration of each receiving antenna is the ratio of the duration to the number of the plurality of receiving antennas. After the plurality of receiving antennas are turned on sequentially, the radar signal is generated by the next transmitting antenna of the transmitting antenna, and so on in a cycle.

[0023] Optionally, in one specific implementation, the radar signal processing module is specifically used for:

[0024] Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the third processing result;

[0025] Based on the second type of phase difference, phase difference compensation is performed on the third processing result to obtain the first compensation result;

[0026] Based on the slow time period dimension, the first compensation result is subjected to Fourier transform to obtain the fourth processing result;

[0027] Based on the first type of phase difference, phase difference compensation is performed on the fourth processing result to obtain the target result.

[0028] Optionally, in one specific implementation, the radar signal processing module is further used for:

[0029] The target result is analyzed to obtain the detection result of the detected target object; wherein the detection result includes at least one of speed, distance and angle.

[0030] In a second aspect, embodiments of the present invention provide a signal processing method applied to the MIMO radar described in any of the first aspects above, the method comprising:

[0031] Multiple transmitting antennas are switched sequentially. When switching to a transmitting antenna, that transmitting antenna is turned on so that it transmits radar signals.

[0032] When each transmitting antenna is turned on, multiple receiving antennas are switched sequentially according to a specified switching mode among a preset multiple switching modes. When switching to a receiving antenna, that receiving antenna is turned on so that it receives the radar echo signal of the radar signal in the specified switching mode. The multiple switching modes include: a first switching mode that controls each receiving antenna to receive the radar echo signal of a complete radar signal, and a second switching mode that controls each receiving antenna to receive the radar echo signal of a portion of a complete radar signal. The multiple receiving antennas share a single receiving link and their operating timing does not overlap.

[0033] If the specified switching mode is the first switching mode, then after switching the multiple transmitting antennas, the received radar echo signal is compensated for the phase difference based on the first type of phase difference caused by switching the multiple transmitting antennas, and the target result is obtained.

[0034] If the specified switching mode is the second switching mode, then after switching the multiple transmitting antennas, phase difference compensation is performed on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas and the second type of phase difference caused by switching the multiple receiving antennas, to obtain the target result.

[0035] Optionally, in one specific implementation, the first switching mode includes:

[0036] When each transmitting antenna is turned on, each receiving antenna sequentially receives the radar echo signal of a complete radar signal transmitted by that transmitting antenna. After all the receiving antennas have received the radar echo signal, the next transmitting antenna of that transmitting antenna transmits the radar signal, and so on in a cycle.

[0037] Optionally, in one specific implementation, the step of performing phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas to obtain the target result includes:

[0038] Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the first processing result;

[0039] Based on the slow time period dimension, the first processing result is subjected to Fourier transform to obtain the second processing result;

[0040] Based on the first type of phase difference, phase difference compensation is performed on the second processing result to obtain the target result.

[0041] Optionally, in one specific implementation, the second switching mode includes:

[0042] When each transmitting antenna is turned on, during the duration of transmitting a complete radar signal, the plurality of receiving antennas are turned on sequentially and receive radar echo signals of a portion of the radar signal transmitted by the transmitting antenna during the turn-on duration. The turn-on duration of each receiving antenna is the ratio of the duration to the number of the plurality of receiving antennas. After the plurality of receiving antennas are turned on sequentially, the radar signal is generated by the next transmitting antenna of the transmitting antenna, and so on in a cycle.

[0043] Optionally, in one specific implementation, the step of performing phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas and the second type of phase difference caused by switching the multiple receiving antennas to obtain the target result includes:

[0044] Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the third processing result;

[0045] Based on the second type of phase difference, phase difference compensation is performed on the third processing result to obtain the first compensation result;

[0046] Based on the slow time period dimension, the first compensation result is subjected to Fourier transform to obtain the fourth processing result;

[0047] Based on the first type of phase difference, phase difference compensation is performed on the fourth processing result to obtain the target result.

[0048] Optionally, in one specific implementation, the method further includes:

[0049] The target result is analyzed to obtain the detection result of the detected target object; wherein the detection result includes at least one of speed, distance and angle.

[0050] Beneficial effects of the embodiments of the present invention:

[0051] As can be seen from the above, the embodiments of the present invention provide a MIMO radar, which includes a transmit gating switch module, a signal generation module, multiple transmit antennas, a receive gating switch module, a signal receiving module, a radar signal processing module, and multiple receive antennas, wherein the multiple receive antennas share a single receive link and their operating timings do not overlap.

[0052] In this system, when the MIMO radar is used to perform various tasks, the signal generation module generates the radar signal transmitted by the MIMO radar. The transmit gating switch module can sequentially switch the multiple transmit antennas, and when switching to a transmit antenna, turn on that transmit antenna so that it transmits the radar signal generated by the signal transmission module. When each transmit antenna is turned on, the receive gating switch module can sequentially switch the multiple receive antennas according to a specified switching mode among a set of preset switching modes. When switching to a receive antenna, turn on that receive antenna so that it receives the radar echo signal of the radar signal transmitted by the turned-on transmit antenna under the specified switching mode. The multiple switching modes may include a first switching mode that controls each receive antenna to receive a radar echo signal of a complete radar signal, and a second switching mode that controls each receive antenna to receive a radar echo signal of a partial radar signal from a complete radar signal. Therefore, when each receive antenna receives a radar echo signal, the signal receiving module can acquire the radar echo signal. Thus, after the receiving gating switch module switches the multiple transmitting antennas, if the specified switching mode is the first switching mode, the radar signal processing device can perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by the switching of the multiple transmitting antennas by the transmitting gating switch module, and obtain the target result. Correspondingly, if the specified switching mode is the second switching mode, the radar signal processing device can perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by the switching of the multiple transmitting antennas by the transmitting gating switch module and the second type of phase difference caused by the switching of the multiple receiving antennas by the receiving gating switch module, and obtain the target result.

[0053] Based on this, the MIMO radar provided in this embodiment of the invention includes multiple receiving antennas and multiple transmitting antennas. Thus, the multiple receiving antennas can be switched sequentially by a receiving gating switch module, and the multiple transmitting antennas can be switched sequentially by a transmitting gating switch module, achieving multiple transmit and multiple receive. Furthermore, since the sequential switching of the multiple receiving antennas by the receiving gating switch module is implemented based on the sequential switching of each transmitting antenna by the transmitting gating switch module, the MIMO radar provided in this embodiment of the invention can achieve dual switching of transmitting and receiving antennas. Furthermore, when processing the radar echo signal, the radar signal processing device can use different phase difference compensation methods according to different switching modes to compensate for the phase difference caused by the switching of transmitting and receiving antennas, thereby reducing the signal-to-noise ratio loss of the obtained task results, improving the accuracy of the obtained target results, and thus improving the radar performance.

[0054] In this way, the phase difference caused by the switching between the transmitting and receiving antennas can be compensated, thereby reducing the signal-to-noise ratio loss of the obtained mission results and improving the performance of the radar, based on the dual switching of the transmitting and receiving antennas.

[0055] Furthermore, in the MIMO radar provided in this embodiment of the invention, since a receive gating switch module is set up to sequentially switch multiple receiving antennas, different receiving antennas can share the same receiving link, and the operating timing of multiple receiving antennas does not overlap, that is, the operating timing of multiple receiving antennas is staggered. In this way, it is not necessary to set up a separate receiving link for each receiving antenna. Therefore, while achieving multiple transmissions and multiple receptions, the system complexity of the radar can be reduced, the radar size can be reduced, and the manufacturing cost of the radar can be reduced.

[0056] Of course, implementing any product or method of the present invention does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0057] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0058] Figure 1 A schematic diagram of the structure of a MIMO radar is provided for an embodiment of the present invention;

[0059] Figure 2 A schematic diagram of signal transmission and reception for an example of the specific implementation method corresponding to step 11;

[0060] Figure 3A schematic diagram of signal transmission and reception for an example of a specific implementation method corresponding to step 21;

[0061] Figure 4 This is a schematic diagram of the gate functions corresponding to each receiving antenna;

[0062] Figure 5 This is a schematic flowchart of a signal processing method for a MIMO radar provided in an embodiment of the present invention. Detailed Implementation

[0063] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art based on this application are within the scope of protection of the present invention.

[0064] In related technologies, when using single-transmitter, multiple-receiver radars to perform various tasks, although random switching of the various receivers (RXs) reduces coupling between them, the switching causes a phase difference when each RX receives the radar echo signal. This results in a loss of signal-to-noise ratio (SNR) in the acquired task results, leading to poor accuracy. Therefore, how to reduce the phase difference caused by RX and TX switching while implementing dual RX and TX switching, thereby minimizing the SNR loss and improving radar performance, has become a pressing problem to be solved.

[0065] To address the aforementioned technical problems, embodiments of the present invention provide a MIMO (Multiple-Input Multiple-Output) radar, which can be understood as a multiple-transmit multiple-receive radar.

[0066] The signal generation module is used to generate the radar signal emitted by the MIMO radar;

[0067] The transmit gating switch module is used to sequentially switch the plurality of transmit antennas. When switched to a transmit antenna, the transmit antenna is turned on so that the transmit antenna transmits the radar signal.

[0068] The receive gating switch module is used to sequentially switch the plurality of receive antennas according to a specified switching mode among a preset plurality of switching modes when each transmit antenna is turned on, and when switching to a receive antenna, turn on that receive antenna so that the receive antenna receives the radar echo signal of the radar signal in the specified switching mode; wherein, the plurality of switching modes include: a first switching mode that controls each receive antenna to receive a radar echo signal of a complete radar signal, and a second switching mode that controls each receive antenna to receive a radar echo signal of a portion of a complete radar signal;

[0069] The signal receiving module is used to acquire the radar echo signal received by each receiving antenna;

[0070] The radar signal processing module is configured to, if the specified switching mode is the first switching mode, perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas after switching the multiple transmitting antennas, to obtain the target result; if the specified switching mode is the second switching mode, perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas and the second type of phase difference caused by switching the multiple receiving antennas after switching the multiple transmitting antennas, to obtain the target result.

[0071] As can be seen from the above, the embodiments of the present invention provide a MIMO radar, which includes a transmit gating switch module, a signal generation module, multiple transmit antennas, a receive gating switch module, a signal receiving module, a radar signal processing module, and multiple receive antennas, wherein the multiple receive antennas share a single receive link and their operating timings do not overlap.

[0072] In this system, when the MIMO radar is used to perform various tasks, the signal generation module generates the radar signal transmitted by the MIMO radar. The transmit gating switch module can sequentially switch the multiple transmit antennas, and when switching to a transmit antenna, turn on that transmit antenna so that it transmits the radar signal generated by the signal transmission module. When each transmit antenna is turned on, the receive gating switch module can sequentially switch the multiple receive antennas according to a specified switching mode among a set of preset switching modes. When switching to a receive antenna, turn on that receive antenna so that it receives the radar echo signal of the radar signal transmitted by the turned-on transmit antenna under the specified switching mode. The multiple switching modes may include a first switching mode that controls each receive antenna to receive a radar echo signal of a complete radar signal, and a second switching mode that controls each receive antenna to receive a radar echo signal of a partial radar signal from a complete radar signal. Therefore, when each receive antenna receives a radar echo signal, the signal receiving module can acquire the radar echo signal. Thus, after the receiving gating switch module switches the multiple transmitting antennas, if the specified switching mode is the first switching mode, the radar signal processing device can perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by the switching of the multiple transmitting antennas by the transmitting gating switch module, and obtain the target result. Correspondingly, if the specified switching mode is the second switching mode, the radar signal processing device can perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by the switching of the multiple transmitting antennas by the transmitting gating switch module and the second type of phase difference caused by the switching of the multiple receiving antennas by the receiving gating switch module, and obtain the target result.

[0073] Based on this, the MIMO radar provided in this embodiment of the invention includes multiple receiving antennas and multiple transmitting antennas. Thus, the multiple receiving antennas can be switched sequentially by a receiving gating switch module, and the multiple transmitting antennas can be switched sequentially by a transmitting gating switch module, achieving multiple transmit and multiple receive. Furthermore, since the sequential switching of the multiple receiving antennas by the receiving gating switch module is implemented based on the sequential switching of each transmitting antenna by the transmitting gating switch module, the MIMO radar provided in this embodiment of the invention can achieve dual switching of transmitting and receiving antennas. Furthermore, when processing the radar echo signal, the radar signal processing device can use different phase difference compensation methods according to different switching modes to compensate for the phase difference caused by the switching of transmitting and receiving antennas, thereby reducing the signal-to-noise ratio loss of the obtained task results, improving the accuracy of the obtained target results, and thus improving the radar performance.

[0074] In this way, the phase difference caused by the switching between the transmitting and receiving antennas can be compensated, thereby reducing the signal-to-noise ratio loss of the obtained mission results and improving the performance of the radar, based on the dual switching of the transmitting and receiving antennas.

[0075] Furthermore, in the MIMO radar provided in this embodiment of the invention, since a receive gating switch module is set up to sequentially switch multiple receiving antennas, different receiving antennas can share the same receiving link, and the operating timing of multiple receiving antennas does not overlap, that is, the operating timing of multiple receiving antennas is staggered. In this way, it is not necessary to set up a separate receiving link for each receiving antenna. Therefore, while achieving multiple transmissions and multiple receptions, the system complexity of the radar can be reduced, the radar size can be reduced, and the manufacturing cost of the radar can be reduced.

[0076] The following is an example illustration of a MIMO radar provided by the present invention, with reference to the accompanying drawings.

[0077] Figure 1 A schematic diagram of a MIMO radar is provided as an embodiment of the present invention. For example... Figure 1 As shown, the MIMO radar includes: a transmit gating switch module 110, a signal generation module 120, multiple transmit antennas TX1-TXN, a receive gating switch module 130, a signal receiving module 140, a radar signal processing module 150, and multiple receive antennas RX1-RXN.

[0078] Furthermore, the aforementioned transmit gating switch module 110, signal generation module 120, multiple transmit antennas TX1-TXN, receive gating switch module 130, signal receiving module 140, radar signal processing module 150, and multiple transmit antennas RX1-RXN are the various hardware components of this MIMO radar.

[0079] The signal generation module 120 is used to generate radar signals transmitted by the MIMO radar, such as FMCW (Frequency Modulated Continues Wave) signals, chirp signals, etc. The present invention does not make specific limitations on this.

[0080] The aforementioned transmit gating switch module 110 can sequentially switch the aforementioned multiple transmit antennas TX1-TXN. When it traverses to a transmit antenna, it turns on the transmit antenna so that the transmit antenna transmits the aforementioned radar signal.

[0081] For example, such as Figure 1As shown, when the transmit gating switch module 110 is switched to transmit antenna TX2, the solid origin in the transmit gating switch module 110 will be connected to the hollow origin at the end of the transmit antenna TX2, thereby enabling the transmit antenna TX2 to conduct. Then, the transmit antenna TX2 can generate the radar signal generated by the signal generation module 120.

[0082] In other words, when the aforementioned transmit gating switch module 110 switches to each transmit antenna, the MIMO radar will switch to the transmit channel corresponding to that transmit antenna, thereby enabling the transmit antenna to transmit the radar signal generated by the aforementioned signal generating module 120.

[0083] In this configuration, when each transmitting antenna is turned on, the other transmitting antennas are in a de-conducting state. Thus, the multiple transmitting antennas TX1-TXN can be switched on and off sequentially by switching them sequentially. Furthermore, the switching order of each transmitting antenna in the transmit gating switch module 110 can be arbitrary, and this embodiment of the invention does not impose specific limitations on it.

[0084] Furthermore, for the aforementioned receiver gating switch module 130, multiple switching modes can be pre-set according to application requirements. Among these preset switching modes, a first switching mode can be included: a first switching mode that controls each receiving antenna to receive a radar echo signal of a complete radar signal, and a second switching mode that controls each receiving antenna to receive a radar echo signal of a partial signal from a complete radar signal.

[0085] Of course, the various switching modes preset above may also include other switching modes besides the first and second switching modes mentioned above.

[0086] In this way, when using the MIMO radar to perform various tasks, a specified switching mode can be determined from the preset multiple switching modes. Then, when each transmitting antenna is turned on, the receiving gating switch module 130 can sequentially switch the multiple receiving antennas RX1-RXN according to the determined specified switching mode. When switching to a receiving antenna, the receiving antenna is turned on so that the receiving antenna receives the radar echo signal of the radar signal in the specified switching mode. The radar echo signal is the echo signal of the radar signal transmitted by the turned-on transmitting antenna.

[0087] In other words, when each transmitting antenna is turned on, the receiving gating switch module 130 can switch the multiple receiving antennas RX1-RXN. When switching to a receiving antenna, the receiving antenna is turned on so that the receiving antenna can receive the radar echo signal.

[0088] For example, such as Figure 1 As shown, when switching to the receiving antenna RX2, the solid origin in the receiving gating switch module 130 will be connected to the hollow origin at the end of the receiving antenna RX2, thereby enabling the receiving antenna RX2 to conduct. Then, the receiving antenna RX2 can receive the radar echo signal of the radar signal sent by the transmitting antenna that is currently conducting in the specified switching mode.

[0089] In this configuration, when each receiving antenna is turned on, the other receiving antennas are in a de-energized state. Thus, the activation of the multiple receiving antennas RX1-RXN can be achieved by sequentially switching them. Furthermore, the switching order of each receiving antenna in the receiving gating switch module 130 during the sequential switching of the multiple receiving antennas RX1-RXN can be arbitrary; this embodiment of the invention does not impose specific limitations on this.

[0090] In this way, by sequentially switching the multiple receiving antennas through the receiving gating switch module 130, the multiple receiving antennas RX1-RXN can be turned on sequentially. As a result, the operating timing of the multiple receiving antennas RX1-RXN can be staggered, that is, the operating timing of the multiple receiving antennas RX1-RXN does not overlap. Furthermore, the multiple receiving antennas RX1-RXN can share a single receiving link, thereby reducing the size and cost of the MIMO radar.

[0091] In other words, in the MIMO radar provided in this embodiment of the invention, multiple receiving antennas share a single receiving link and their operating timings do not overlap.

[0092] After each receiving antenna receives the radar echo signal, it can transmit the radar echo signal to the signal receiving module 140. In other words, the signal receiving module 140 can be used to acquire the radar echo signal received by each receiving antenna.

[0093] Thus, during the process of the transmit gating switch module 110 sequentially switching the multiple transmit antennas TX1-TXN, the signal receiving module 140 can acquire all the radar echo signals received by each receiving antenna during the process, and transmit the acquired radar echo signals to the radar signal processing module 150.

[0094] Furthermore, after the transmit gating switch module 110 has switched the multiple transmit antennas TX1-TXN, the radar signal processing module 150 can perform phase difference compensation on all received radar echo signals according to the phase difference compensation method corresponding to the specified switching mode adopted by the receive gating switch module 130, and obtain the target result.

[0095] If the specified switching mode is the first switching mode that controls each receiving antenna to receive a complete radar signal, then after the transmit gating switch module 110 switches the multiple transmit antennas TX1-TXN, the radar signal processing module 150 can perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by the transmit gating switch module 110 switching the multiple transmit antennas, and obtain the target result.

[0096] Accordingly, if the specified switching mode is the second switching mode that controls each receiving antenna to receive a portion of the radar echo signal from a complete radar signal, then after the transmit gating switch module 110 switches the multiple transmit antennas TX1-TXN, the radar signal processing module 150 performs phase difference compensation on the received radar echo signal based on the first type of phase difference caused by the transmit gating switch module 110 switching the multiple transmit antennas, and the second type of phase difference caused by the receive gating switch module 130 switching the multiple receive antennas, to obtain the target result.

[0097] Optionally, in one specific implementation, the radar signal processing module 150 described above can also be used for:

[0098] The target results are analyzed to obtain the detection results of the detected target objects; the detection results include at least one of speed, distance and angle.

[0099] In this specific implementation, after obtaining the target result, the radar signal processing module 150 can analyze the target signal to obtain the detection result of the target object detected by the MIMO radar.

[0100] Furthermore, the detection result includes at least one of the following: speed, distance, and angle. Speed ​​refers to the moving speed of the target object detected by the MIMO radar; distance refers to the distance between the target object and the MIMO radar; and angle refers to the pose angle of the target object relative to the MIMO radar.

[0101] For example, the target results can be analyzed to obtain the moving speed of the target object detected by the MIMO radar, the distance of the target object from the MIMO radar, and the pose angle of the target object relative to the MIMO radar.

[0102] As can be seen from the above, the MIMO radar provided in this embodiment of the invention includes multiple receiving antennas and multiple transmitting antennas. Therefore, the multiple receiving antennas can be switched sequentially by a receiving gating switch module, and the multiple transmitting antennas can be switched sequentially by a transmitting gating switch module, achieving multiple transmit and multiple receive. Furthermore, since the sequential switching of the multiple receiving antennas by the receiving gating switch module is implemented based on the sequential switching of each transmitting antenna by the transmitting gating switch module, the MIMO radar provided in this embodiment of the invention can achieve dual switching of transmitting and receiving antennas. Furthermore, when processing the radar echo signal, the radar signal processing device can use different phase difference compensation methods according to different switching modes to compensate for the phase difference caused by the switching of transmitting and receiving antennas, thereby reducing the signal-to-noise ratio loss of the obtained task results, improving the accuracy of the obtained target results, and thus improving the radar performance.

[0103] In this way, the phase difference caused by the switching between the transmitting and receiving antennas can be compensated, thereby reducing the signal-to-noise ratio loss of the obtained mission results and improving the performance of the radar, based on the dual switching of the transmitting and receiving antennas.

[0104] Furthermore, in the MIMO radar provided in this embodiment of the invention, since a receive gating switch module is set up to sequentially switch multiple receiving antennas, different receiving antennas can share the same receiving link, and the operating timing of multiple receiving antennas does not overlap, that is, the operating timing of multiple receiving antennas is staggered. In this way, it is not necessary to set up a separate receiving link for each receiving antenna. Therefore, while achieving multiple transmissions and multiple receptions, the system complexity of the radar can be reduced, the radar size can be reduced, and the manufacturing cost of the radar can be reduced.

[0105] Below, examples are provided to illustrate each of the various switching modes included in the aforementioned preset switching modes.

[0106] Optionally, in one specific implementation, the first switching mode for controlling each receiving antenna to receive a radar echo signal of a complete radar signal may include: when each transmitting antenna is turned on, each receiving antenna sequentially receives the radar echo signal of a complete radar signal transmitted by that transmitting antenna; after multiple receiving antennas have received radar echo signals, the next transmitting antenna of that transmitting antenna transmits the radar signal, and so on in a loop.

[0107] Thus, when the specified switching mode is the first switching mode, the receive gating switch module 130 can sequentially switch multiple receive antennas RX1-RXN when each transmit antenna is turned on. When switching to a receive antenna, the receive antenna is turned on so that it receives the radar echo signal of the radar signal transmitted by the currently turned-on transmit antenna, until the receive antenna has received the radar echo signal of a complete radar signal transmitted by the currently turned-on transmit antenna. Then, the receive gating switch module 130 can switch to the next receive antenna.

[0108] In other words, when the aforementioned transmit gating module 110 switches to a certain transmit antenna, thereby activating that transmit antenna, it can continuously transmit various radar signals. At this time, the aforementioned receive gating module 130 can switch to the first receive antenna and activate it, allowing the activated receive antenna to receive radar echo signals. Furthermore, when the transmit antenna completes the transmission of a full radar signal, the activated receive antenna can receive the radar echo signal of that full radar signal. Then, the aforementioned receive gating module 130 can switch to the next receive antenna, that is, switch the activated receive antenna from the first receive antenna to the next receive antenna. Afterwards, the transmit antenna begins transmitting the next radar signal, and the switched-to next receive antenna begins receiving the radar echo signal of that next radar signal, until the transmit antenna completes the transmission of the next full radar signal, that is, the transmit antenna completes the transmission of another full radar signal, and the switched-to next receive antenna can receive the radar echo signal of a full radar signal. This process continues in a loop until the receiver selection switch module 130 switches to the last receiving antenna, turning it on. At this point, the transmitting antenna begins transmitting a new radar signal again, and the last receiving antenna receives the radar echo signal of this new radar signal. This continues until the transmitting antenna has completely transmitted the new radar signal, and the last receiving antenna can also receive the radar echo signal of a complete radar signal. Thus, the conduction process of the transmitting antenna is complete.

[0109] In the current conduction process of the aforementioned conducting transmitting antenna, the conduction time of each receiving antenna is: the time for the transmitting antenna to transmit a complete radar signal, and the conduction time of the transmitting antenna is: the total time for transmitting a complete radar signal from the multiple receiving antennas included in the MIMO radar.

[0110] Thus, if the transmitting antenna is not the last transmitting antenna, the transmitting gating switch module 110 will switch the activated transmitting antenna to the next transmitting antenna and repeat the sequential activation process of each receiving antenna.

[0111] Optionally, if the transmitting antenna is the last transmitting antenna, the transmitting gating switch module 110 can switch the activated transmitting antenna to the first transmitting antenna and repeat the sequential activation process of each receiving antenna.

[0112] Optionally, if the transmitting antenna is the last transmitting antenna, it can be determined that the MIMO radar has completed its task and stopped working; or, according to the working requirements, after a specified interval, the transmitting gating switch module 110 switches the activated transmitting antenna back to the first transmitting antenna and repeats the sequential activation process of each receiving antenna.

[0113] For example, assuming a MIMO radar includes two transmit antennas TX1 and TX2, and four receive antennas RX1, RX2, RX3, and RX4, then in this specific implementation, after the transmit gating switch module sequentially switches the two transmit antennas TX1 and TX2, the resulting signal diagram is shown below. Figure 2 As shown.

[0114] First, the transmitting gating switch module activates the transmitting antenna TX1, which then transmits a radar signal. The receiving gating switch module activates the receiving antenna RX1 to receive the radar echo signal. After transmitting a complete radar signal, TX1 transmits the next radar signal, and the receiving gating switch module switches the activated receiving antenna to receiving antenna RX2, which then receives the radar echo signal. After transmitting a complete radar signal, TX1 transmits the next radar signal, and the receiving gating switch module switches the activated receiving antenna to receiving antenna RX3, which then receives the radar echo signal. After transmitting a complete radar signal, TX1 transmits the next radar signal, and the receiving gating switch module switches the activated receiving antenna to receiving antenna RX4, which then receives the radar echo signal.

[0115] Subsequently, the transmit gating module switches the activated transmit signal to transmit antenna TX2. Then, transmit antenna TX2 transmits radar signals, and the receive gating module activates receive antenna RX1 to receive the radar echo signal. After transmit antenna TX2 transmits a complete radar signal, it transmits the next radar signal. The receive gating module then switches the activated receive antenna to receive antenna RX2, which receives the radar echo signal. After transmit antenna TX2 transmits a complete radar signal, it transmits the next radar signal. The receive gating module then switches the activated receive antenna to receive antenna RX3, which receives the radar echo signal. After transmit antenna TX2 transmits a complete radar signal, it transmits the next radar signal. The receive gating module then switches the activated receive antenna to receive antenna RX4, which receives the radar echo signal. This completes one switching of transmit antennas TX1 and TX2.

[0116] Optionally, based on the aforementioned first switching mode, the radar signal processing module 150 can specifically execute the following steps 11-13:

[0117] Step 11: Based on the fast time sampling point dimension, perform Fourier transform on the received radar echo signal to obtain the first processing result;

[0118] Step 12: Based on the slow time period dimension, perform a Fourier transform on the first processing result to obtain the second processing result;

[0119] Step 13: Based on the first type of phase difference, perform phase difference compensation on the second processing result to obtain the target result.

[0120] In this specific implementation, after the transmit gating switch module 110 sequentially switches the multiple transmit antennas TX1-TXN and obtains all the radar echo signals received by each receive antenna, the radar signal processing module 150 can first perform Fourier transform on each received radar echo signal based on the fast time sampling point dimension to obtain the first processing result.

[0121] The term "fast time" refers to the number of preset sampling points within a frequency modulation cycle, and the duration of the frequency modulation cycle is the time it takes for the transmitting antenna to transmit a complete radar signal.

[0122] Therefore, the radar signal processing module 150 can perform a Fourier transform on the first processing result based on the slow time period dimension to obtain the second processing result.

[0123] The so-called slow time can be understood as PRF (pulse repetition frequency), which represents the number of pulses emitted per second. Its value is the reciprocal of the pulse repetition interval (PRI). The pulse repetition interval refers to the time interval between one pulse and the next pulse.

[0124] In this specific implementation, since the conduction time of each receiving antenna is the same as the time it takes for the transmitting antenna to transmit a complete radar signal, the phase difference caused by switching the transmitting antenna is the same as the phase difference caused by switching the receiving antenna.

[0125] In this way, the radar signal processing module 150 can perform phase difference compensation on the second processing result based on the first type of phase difference caused by switching the multiple transmitting antennas, and obtain the target result.

[0126] Optionally, the radar echo signals received by each receiving antenna can be represented as:

[0127]

[0128] Where k represents the k-th fast time sampling point; n represents the n-th slow time period; m represents the m-th set of conducting receiving and transmitting antennas, and the receiving and transmitting antennas in any two sets of conducting receiving and transmitting antennas are not exactly the same; A represents the amplitude of the radar signal echo; B is the frequency modulation bandwidth of the radar signal; T c T is the frequency modulation period of a single radar signal; s The fast time sampling interval is c; the speed of light is f. d =2v / λ is the Doppler frequency, and λ is the wavelength; T MIMO The MIMO radar provided in this embodiment of the invention sequentially switches the period duration of each transmitting antenna; φ(m,θ) is the phase term related to the spatial angle θ, where θ is the pose angle of the detected target object relative to the MIMO radar, r is the abbreviation for "receive", j represents the imaginary unit, and exp is the abbreviation for "exponential curve", representing an exponential function with the natural constant e as its base.

[0129] by Figure 2 Taking a MIMO radar with 2 TX and 4 RX as an example, the m in the radar echo signal received by each of the above receiving antennas will be explained.

[0130] Among them, targeting Figure 2The corresponding MIMO radar, which includes 2 TX and 4 RX, has eight sets of conducting receiving and transmitting antennas during the sequential switching of each TX, and can be represented as follows:

[0131] Group 1: m = 1, where the TX that is turned on is TX1 and the RX that is turned on is RX1;

[0132] The second group: m = 2, where the TX that is conducting is TX1 and the RX that is conducting is RX2;

[0133] The third group: m = 3, where the TX that is turned on is TX1 and the RX that is turned on is RX3;

[0134] Group 4: m = 4, where the TX that is conducting is TX1 and the RX that is conducting is RX4;

[0135] Group 5: m = 5, where the TX that is conducting is TX2 and the RX that is conducting is RX1;

[0136] Group 6: m = 6, where the TX that is conducting is TX2 and the RX that is conducting is RX2;

[0137] Group 7: m = 7, where the TX that is conducting is TX2 and the RX that is conducting is RX3;

[0138] Group 8: m = 8, where the TX that is conducting is TX2 and the RX that is conducting is RX4.

[0139] Each set of conducting receiving and transmitting antennas can be referred to as a channel.

[0140] Furthermore, based on the dimension of fast time sampling points, performing a Fourier transform on the aforementioned radar echo signal yields the following first processing result:

[0141] f1(a,n,m), a=1,2,...,N a ; where N a The fast-time Fourier transform has a number of points, and the first processing result is a three-dimensional matrix.

[0142] Then, based on the slow time period dimension, a Fourier transform is performed on the above first processing result to obtain the following second processing result:

[0143] f2(a,b,m), b=1,2,...,N b ; where N b This represents the number of points in the slow-time Fourier transform.

[0144] Next, based on the first type of phase difference, phase difference compensation can be performed on the second processing result to obtain the following target result:

[0145] f3(a,b,m)=f2(a,b,m)×exp(-j(m-1)2πf d T c )

[0146] Based on this, we can perform a Fourier transform on f3 based on the combined dimensions of the receiving and transmitting antennas to obtain f4(a,b,c); where c = 1,2,…,N C N C The number of Fourier transform points in the dimension of the combined receiving and transmitting antennas.

[0147] Then, a peak search can be performed on the magnitude of f4(a,b,c). The peak value found represents the target object detected by the MIMO radar. Thus, the coordinate index of the target object in f4(a,b,c) can be obtained. The coordinate index is represented as (a1, b1, c1), where a1 represents the distance of the target object detected by the MIMO radar from the MIMO radar, b1 represents the moving speed of the target object detected by the MIMO radar, and c1 represents the pose angle of the target object detected by the MIMO radar relative to the MIMO radar.

[0148] Optionally, in one specific implementation, the second switching mode for controlling each receiving antenna to receive a portion of the radar echo signal from a complete radar signal may include: when each transmitting antenna is turned on, during the duration of the transmitting antenna transmitting a complete radar signal, multiple receiving antennas are sequentially turned on and receive the radar echo signal of the portion of the radar signal transmitted by the transmitting antenna during the on-time, wherein the on-time of each receiving antenna is the ratio of the duration to the number of multiple receiving antennas; after multiple receiving antennas are sequentially turned on, the next transmitting antenna of the transmitting antenna generates a radar signal, and so on in a cycle.

[0149] Thus, when the specified switching mode is the second mode, when each transmitting antenna is turned on, during the duration of the transmitting antenna transmitting a complete radar signal, the receiving gating switch module 130 can sequentially switch multiple receiving antennas RX1-RXN. When switching to a receiving antenna, the receiving antenna is turned on so that the receiving antenna receives the radar echo signal of the radar signal transmitted by the currently turned-on transmitting antenna, until the turn-on duration of the receiving antenna reaches a certain duration. At this time, the receiving antenna receives the radar echo signal of part of the radar signal transmitted by the transmitting antenna; then, the receiving gating switch module 130 can switch to the next receiving antenna.

[0150] Since all receiving antennas RX1-RXN need to be switched sequentially during the duration of a complete radar signal transmitted by the transmitting antenna, the conduction time of each receiving antenna is the ratio of the duration of a complete radar signal transmitted by the transmitting antenna to the number of the multiple receiving antennas.

[0151] In other words, during the duration of a complete radar signal transmitted by the currently activated transmitting antenna, the aforementioned receiving gating switch module 130 sequentially activates the aforementioned multiple receiving antennas RX1-RXN, and each activated receiving antenna can receive radar echo signals of a portion of a complete radar signal.

[0152] First, the duration of a complete radar signal transmitted by the transmitting antenna and the number of the multiple receiving antennas RX1-RXN can be determined. Then, the ratio of the duration of a complete radar signal transmitted by the transmitting antenna to the number of the multiple receiving antennas can be calculated. This ratio is used as the conduction duration of each receiving antenna within the duration of a complete radar signal transmitted by the currently active transmitting antenna. For ease of description, the conduction duration of each receiving antenna within the duration of a complete radar signal transmitted by the currently active transmitting antenna can be simply referred to as the specified duration.

[0153] Thus, when the aforementioned transmit gating module 110 switches to a certain transmit antenna, and the transmit antenna is activated, it can begin transmitting a radar signal. Furthermore, during the duration of transmitting the radar signal, the aforementioned receive gating module 130 can switch to the first receive antenna and activate it, allowing the activated receive antenna to receive the radar echo signal. When the activation duration of the receive antenna reaches the specified duration, the activated receive antenna can receive the radar echo signal of a portion of the radar signal transmitted by the transmit antenna. Then, the aforementioned receive gating module 130 can switch to the next receive antenna, that is, switch the activated receive antenna from the first receive antenna to the next receive antenna. At this time, the transmit antenna continues to continuously transmit the aforementioned radar signal, and the switched-to next receive antenna begins to receive the radar echo signal of the radar signal until the activation duration of the receive antenna reaches the specified duration, at which point the switched-to next receive antenna can receive the radar echo signal of a portion of the radar signal transmitted by the transmit antenna. This process continues in a loop until the receiver selection switch module 130 switches to the last receiving antenna, turning it on. During this time, the transmitting antenna continues to transmit the radar signal, and the last receiving antenna receives the radar echo signal. This continues until the last receiving antenna has been on for a specified duration. Then, the last receiving antenna can also receive the radar echo signal of a portion of the radar signal transmitted by the transmitting antenna. At this point, the conduction process of the transmitting antenna is complete, and during its conduction, the transmitting antenna transmits a complete radar signal.

[0154] In the current conduction process of the aforementioned conducting transmitting antenna, the conduction duration of each receiving antenna is the ratio of the duration of the transmitting antenna transmitting a complete radar signal to the number of multiple receiving antennas, and the conduction duration of the transmitting antenna is the duration of transmitting a complete radar signal.

[0155] Thus, if the transmitting antenna is not the last transmitting antenna, the transmitting gating switch module 110 will switch the activated transmitting antenna to the next transmitting antenna and repeat the sequential activation process of each receiving antenna.

[0156] Optionally, if the transmitting antenna is the last transmitting antenna, the transmitting gating switch module 110 will switch the activated transmitting antenna to the first transmitting antenna and repeat the sequential activation process of each receiving antenna.

[0157] Optionally, if the transmitting antenna is the last transmitting antenna, it can be determined that the MIMO radar has completed its task and stopped working; or, according to the working requirements, after a specified interval, the transmitting gating switch module 110 switches the activated transmitting antenna back to the first transmitting antenna and repeats the sequential activation process of each receiving antenna.

[0158] For example, assuming a MIMO radar includes two transmit antennas TX1 and TX2, and four receive antennas RX1, RX2, RX3, and RX4, then in this specific implementation, after the transmit gating switch module sequentially switches the two transmit antennas TX1 and TX2, the resulting signal diagram is shown below. Figure 3 As shown.

[0159] The duration of a complete radar signal transmitted by the transmitting antenna is T. c That is, the frequency modulation period of a single radar signal is T. c If the number of receiving antennas RX1-RXN is 4, then during the conduction process of the currently activated transmitting antenna, the conduction time of each receiving antenna is T. c / 4, thus, the duration T of transmitting a complete radar signal from the transmitting antenna can be determined. c Within this timeframe, the receiving antenna RX1 operates in time 0-T. c / 4 hours after conduction; receiving antenna RX2 is activated at time T c / 4-2T c / 4 hours to conduct; receiving antenna RX3 is activated within time 2T. c / 4-3T c RX4 conducts within 4 seconds; RX4 conducts within 3T time. c / 4-T c Internal conduction.

[0160] Thus, firstly, the transmitting gating switch module activates the transmitting antenna TX1, which transmits radar signals; secondly, the receiving gating switch module activates the receiving antenna RX1 to receive radar echo signals; and thirdly, when the time for transmitting antenna TX1 to transmit radar signals reaches T... c At / 4, the receive gating switch module switches the activated receive antenna to receive antenna RX2, and this receive antenna RX2 receives the radar echo signal; when the transmit antenna TX1 transmits the radar signal for 2T... c At / 4, the receive gating switch module switches the activated receive antenna to receive antenna RX3, and receive antenna RX3 receives the radar echo signal; when the transmit antenna TX1 transmits the radar signal for 3T... c When / 4, the receiving gating switch module switches the activated receiving antenna to receiving antenna RX4, and receiving antenna RX4 receives radar echo signals.

[0161] The time for transmitting radar signals via transmitting antenna TX1 reaches T. c At that time, the transmit gating switch module switches the activated transmit signal to transmit antenna TX2, and the receive gating switch module switches the activated receive antenna to receive antenna RX1, which receives the radar echo signal; when the transmit antenna TX2 transmits the radar signal for a period of time T... c At / 4, the receive gating switch module switches the activated receive antenna to receive antenna RX2, and this receive antenna RX2 receives the radar echo signal; when the transmit antenna TX2 transmits the radar signal for 2T... c At / 4, the receive gating switch module switches the activated receive antenna to receive antenna RX3, and this receive antenna RX3 receives the radar echo signal; when the transmit antenna TX2 transmits the radar signal for 3T... c When / 4, the receiving gating switch module switches the activated receiving antenna to receiving antenna RX4, and receiving antenna RX4 receives radar echo signals.

[0162] The time for transmitting radar signals via transmitting antenna TX2 reaches T. c At this point, the receiving antenna RX4 is turned off, thus completing one switch between the transmitting antennas TX1 and TX2.

[0163] Optionally, based on the aforementioned second switching mode, the radar signal processing module 150 can specifically execute the following steps 21-24:

[0164] Step 21: Based on the fast time sampling point dimension, perform Fourier transform on the received radar echo signal to obtain the third processing result;

[0165] Step 22: Based on the second type of phase difference, perform phase difference compensation on the third processing result to obtain the first compensation result;

[0166] Step 23: Based on the slow time period dimension, perform a Fourier transform on the first compensation result to obtain the fourth processing result;

[0167] Step 24: Based on the first type of phase difference, perform phase difference compensation on the fourth processing result to obtain the target result.

[0168] In this specific implementation, after the transmit gating switch module 110 sequentially switches the multiple transmit antennas TX1-TXN, and after obtaining all the radar echo signals received by each receive antenna, the radar signal processing module 150 can first perform Fourier transform on each received radar echo signal based on the fast time sampling point dimension to obtain the third processing result.

[0169] In this process, the operating timing of the multiple receiving antennas RX1-RXN is staggered during the continuous transmission of a complete radar signal. In other words, the radar echo signal received by each receiving antenna is the radar echo signal corresponding to the complete radar signal multiplied by the gate function corresponding to that receiving antenna.

[0170] For example, when the number of the aforementioned multiple receiving antennas RX1-RXN is 4, such as Figure 4 The diagram shows the gate functions corresponding to each receiving antenna. Therefore, the radar echo signals received by each receiving antenna are:

[0171] s(k,n,1)=s×g1

[0172] s(k,n,2)=s×g2

[0173] s(k,n,3)=s×g3

[0174] s(k,n,4)=s×g4

[0175] Where s represents the radar echo signal corresponding to the complete radar signal, s(k,n,m) represents the radar echo signal received by the m-th receiving antenna in the nth slow time period, and g m This represents the gate function corresponding to the m-th receiving antenna.

[0176] Considering the time delay between the radar echo signals received by different receiving antennas, the third processing result obtained above contains a second type of phase difference, namely, a phase difference caused by switching the multiple receiving antennas. Therefore, phase difference compensation can be performed on the third processing result based on this second type of phase difference caused by switching the multiple receiving antennas, resulting in a first compensation result.

[0177] Optionally, the second type of phase difference mentioned above can be:

[0178] exp(-j2π(m-1)aΔN / N a ); where ΔN represents the time delay between radar echo signals received by different receiving antennas.

[0179] After obtaining the first compensation result, a Fourier transform can be performed on the first compensation result based on the slow time period dimension to obtain the fourth processing result.

[0180] In this specific implementation, since the transmitting antennas are switched after each transmitting antenna transmits a complete radar signal, a first-type phase difference exists due to the switching of the multiple transmitting antennas. Therefore, phase difference compensation can be performed on the fourth processing result based on the first-type phase difference caused by the switching of each of the multiple transmitting antennas, thus obtaining the target result.

[0181] Optionally, the radar echo signals received by each receiving antenna can be represented as:

[0182]

[0183] Furthermore, based on the dimension of fast time sampling points, performing a Fourier transform on the aforementioned radar echo signal yields the following third processing result:

[0184] f1(a,n,m), a=1,2,...,N a ; where N a The fast-time Fourier transform has a number of points, and the first processing result is a three-dimensional matrix.

[0185] Subsequently, based on the second type of phase difference mentioned above, phase difference compensation is performed on the third processing result to obtain the following first compensation result:

[0186] f1′=f1(a,n,m)×exp(-j2π(m RX -1)aΔN / N a )

[0187] Where, m RX This represents the receiving antenna in the m-th group of transmitting and receiving antennas that are in operation.

[0188] Furthermore, since each set of conducting receiving and transmitting antennas can be considered a channel, then m RX This can be understood as: the receiving antenna corresponding to the m-th channel, that is, the receiving antenna corresponding to each channel is the receiving antenna that is currently being conducted.

[0189] Then, based on the slow time period dimension, a Fourier transform is performed on the above first compensation result, which yields the following fourth processing result:

[0190] f2(a,b,m), b=1,2,...,N b ; where N b This represents the number of points in the slow-time Fourier transform.

[0191] Next, based on the first type of phase difference mentioned above, phase difference compensation can be performed on the second processing result to obtain the following target result:

[0192] f3(a,b,m)=f2(a,b,m)×exp(-j(m TX -1)2πf d T c )

[0193] Where, m TX This represents the transmitting antenna in the m-th group of transmitting and receiving antennas.

[0194] Furthermore, since each set of conducting receiving and transmitting antennas can be considered a channel, then m TX This can be understood as: the transmitting antenna corresponding to the m-th channel, that is, the transmitting antenna corresponding to each channel is the transmitting antenna that is currently being conducted.

[0195] by Figure 2 Taking a MIMO radar with 2 TX and 4 RX as an example, regarding the m in the first compensation result mentioned above... RX and m TX Please provide an explanation.

[0196] Among them, targeting Figure 2 The corresponding MIMO radar includes 2 TX and 4 RX antennas. During the sequential activation of each TX, there are eight sets of activated receiving and transmitting antennas, i.e., eight channels. Each channel can be represented as follows:

[0197] First channel: m = 1, m TX =1,m RX =1, meaning that the TX corresponding to the first channel is TX1 and the RX corresponding to the first channel is RX1; at this time, TX1 and RX1 are turned on.

[0198] Second channel: m = 2, m TX =1,m RX =2, meaning the TX corresponding to the second channel is TX1, and the RX corresponding to the second channel is RX2; at this time, TX1 and RX2 are turned on;

[0199] The third channel: m = 3, m TX =1,m RX =3, meaning the TX corresponding to the third channel is TX1, and the RX corresponding to the third channel is RX3; at this time, TX1 and RX3 are turned on;

[0200] Fourth channel: m = 4, m TX =1,m RX =4, meaning the TX corresponding to the fourth channel is TX1, and the RX corresponding to the fourth channel is RX4; at this time, TX1 and RX4 are turned on.

[0201] Fifth channel: m = 5, mTX =2,m RX =1, meaning the TX corresponding to the fifth channel is TX2, and the RX corresponding to the fifth channel is RX1; at this time, TX2 and RX1 are turned on;

[0202] Sixth channel: m = 6, m TX =2,m RX =2, meaning that the TX corresponding to the sixth channel is TX2, and the RX corresponding to the sixth channel is RX2; at this time, TX2 and RX2 are turned on;

[0203] Seventh channel: m = 7, m TX =2,m RX =3, meaning the TX corresponding to the seventh channel is TX2, and the RX corresponding to the seventh channel is RX3; at this time, TX2 and RX3 are turned on;

[0204] Eighth channel: m = 8, m TX =2,m RX =4, meaning the TX corresponding to the eighth channel is TX2, and the RX corresponding to the eighth channel is RX4; at this time, TX2 and RX4 are turned on.

[0205] Based on this, we can perform a Fourier transform on f3 based on the combined dimensions of the receiving and transmitting antennas to obtain f4(a,b,c); where c = 1,2,…,N C N C The number of Fourier transform points in the dimension of the combined receiving and transmitting antennas.

[0206] Then, a peak search can be performed on the magnitude of f4(a,b,c). The peak value found represents the target object detected by the MIMO radar. Thus, the coordinate index of the target object in f4(a,b,c) can be obtained. The coordinate index is represented as (a1, b1, c1), where a1 represents the distance of the target object detected by the MIMO radar from the MIMO radar, b1 represents the moving speed of the target object detected by the MIMO radar, and c1 represents the pose angle of the target object detected by the MIMO radar relative to the MIMO radar.

[0207] Corresponding to the MIMO radar provided in the above embodiments of the present invention, the present invention also provides a signal processing method applied to the above MIMO radar.

[0208] Figure 5 This invention provides a signal processing method that can be applied to any type of MIMO radar provided in this invention. For example... Figure 5 As shown, the method may include the following steps S501-S504:

[0209] S501: Sequentially switch multiple transmitting antennas. When switching to a transmitting antenna, turn on that transmitting antenna so that it transmits radar signals.

[0210] The radar signal is generated by the signal generation module in the MIMO radar provided in this embodiment of the invention, and the sequential switching of the multiple transmitting antennas is achieved by the transmit gating switch module in the MIMO radar provided in this embodiment of the invention.

[0211] S502: When each transmitting antenna is turned on, multiple receiving antennas are switched sequentially according to a specified switching mode among a variety of preset switching modes. When switching to a receiving antenna, the receiving antenna is turned on so that the receiving antenna receives the radar echo signal of the radar signal in the specified switching mode.

[0212] The multiple switching modes include: a first switching mode that controls each receiving antenna to receive a radar echo signal of a complete radar signal, and a second switching mode that controls each receiving antenna to receive a radar echo signal of a portion of a complete radar signal, wherein the multiple receiving antennas share a single receiving link and their operating timings do not overlap.

[0213] Furthermore, the sequential switching of the aforementioned multiple receiving antennas is achieved through the receiving gating switch module in the MIMO radar provided in this embodiment of the invention, and the aforementioned multiple receiving antennas share a single receiving link and their operating timings do not overlap.

[0214] S503: If the specified switching mode is the first switching mode, then after switching the plurality of transmitting antennas, the received radar echo signal is compensated for phase difference based on the first type of phase difference caused by switching the plurality of transmitting antennas, and the target result is obtained.

[0215] S504: If the specified switching mode is the second switching mode, then after switching the plurality of transmitting antennas, phase difference compensation is performed on the received radar echo signal based on the first type of phase difference caused by switching the plurality of transmitting antennas and the second type of phase difference caused by switching the plurality of receiving antennas, to obtain the target result.

[0216] In this embodiment, each receiving antenna, upon receiving a radar echo signal, can transmit the radar echo signal to the signal receiving module in the MIMO radar provided by this invention. The signal receiving module then transmits the acquired radar echo signal to the radar signal processing module in the MIMO radar provided by this invention. In this way, the radar signal processing module can execute steps S503 or S504 according to the specified switching mode, thereby processing the received radar echo signal and obtaining the target result.

[0217] As can be seen from the above, in the signal processing method for MIMO radar provided by the embodiments of the present invention, since there is dual switching between the transmitting and receiving antennas, different phase difference compensation methods can be used according to different switching modes to compensate for the phase difference caused by the switching between the transmitting and receiving antennas. This reduces the signal-to-noise ratio loss of the obtained task results, improves the accuracy of the obtained target results, and thus improves the radar performance. In this way, based on the dual switching between the transmitting and receiving antennas, the phase difference caused by the switching between the transmitting and receiving antennas can be compensated to reduce the signal-to-noise ratio loss of the obtained task results and improve the radar performance.

[0218] Optionally, in one specific implementation, the first switching mode includes: when each transmitting antenna is turned on, each receiving antenna sequentially receives the radar echo signal of a complete radar signal transmitted by the transmitting antenna; after all the receiving antennas have received the radar echo signal, the next transmitting antenna of the transmitting antenna transmits the radar signal, and so on in a loop.

[0219] Optionally, in one specific implementation, step S503 above, which involves performing phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas to obtain the target result, includes:

[0220] Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the first processing result;

[0221] Based on the slow time period dimension, the first processing result is subjected to Fourier transform to obtain the second processing result;

[0222] Based on the first type of phase difference, phase difference compensation is performed on the second processing result to obtain the target result.

[0223] Optionally, in one specific implementation, the second switching mode includes:

[0224] When each transmitting antenna is turned on, during the duration of transmitting a complete radar signal, the plurality of receiving antennas are turned on sequentially and receive radar echo signals of a portion of the radar signal transmitted by the transmitting antenna during the turn-on duration. The turn-on duration of each receiving antenna is the ratio of the duration to the number of the plurality of receiving antennas. After the plurality of receiving antennas are turned on sequentially, the radar signal is generated by the next transmitting antenna of the transmitting antenna, and so on in a cycle.

[0225] Optionally, in one specific implementation, step S504 above, which involves performing phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas and the second type of phase difference caused by switching the multiple receiving antennas, to obtain the target result, includes:

[0226] Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the third processing result;

[0227] Based on the second type of phase difference, phase difference compensation is performed on the third processing result to obtain the first compensation result;

[0228] Based on the slow time period dimension, the first compensation result is subjected to Fourier transform to obtain the fourth processing result;

[0229] Based on the first type of phase difference, phase difference compensation is performed on the fourth processing result to obtain the target result.

[0230] Optionally, in one specific implementation, the signal processing method provided in the above embodiments of the present invention further includes:

[0231] The target result is analyzed to obtain the detection result of the detected target object; wherein the detection result includes at least one of speed, distance and angle.

[0232] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially 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, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. 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 integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk (SSD)).

[0233] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0234] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments. In particular, the method embodiments are basically similar to the MIMO radar embodiments, so the description is relatively simple; relevant parts can be referred to the description of the method embodiments.

[0235] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A MIMO radar, characterized by The MIMO radar includes: a transmit gating switch module, a signal generation module, multiple transmit antennas, a receive gating switch module, a signal receiving module, a radar signal processing module, and multiple receive antennas, wherein the multiple receive antennas share a single receive link and their operating timings do not overlap; The signal generation module is used to generate the radar signal emitted by the MIMO radar; The transmit gating switch module is used to sequentially switch the plurality of transmit antennas. When switched to a transmit antenna, the transmit antenna is turned on so that the transmit antenna transmits the radar signal. The receive gating switch module is used to sequentially switch the plurality of receive antennas according to a specified switching mode among a preset plurality of switching modes when each transmit antenna is turned on, and when switching to a receive antenna, turn on that receive antenna so that the receive antenna receives the radar echo signal of the radar signal in the specified switching mode; wherein, the plurality of switching modes include: a first switching mode that controls each receive antenna to receive a radar echo signal of a complete radar signal, and a second switching mode that controls each receive antenna to receive a radar echo signal of a portion of a complete radar signal; The signal receiving module is used to acquire the radar echo signal received by each receiving antenna; The radar signal processing module is configured to, if the specified switching mode is the first switching mode, perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas after switching the multiple transmitting antennas, to obtain the target result; if the specified switching mode is the second switching mode, perform phase difference compensation on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas and the second type of phase difference caused by switching the multiple receiving antennas after switching the multiple transmitting antennas, to obtain the target result.

2. The MIMO radar according to claim 1, characterized in that, The first switching mode includes: When each transmitting antenna is turned on, each receiving antenna sequentially receives the radar echo signal of a complete radar signal transmitted by that transmitting antenna. After all the receiving antennas have received the radar echo signal, the next transmitting antenna of that transmitting antenna transmits the radar signal, and so on in a cycle.

3. The MIMO radar according to claim 1 or 2, characterized in that, The radar signal processing module is specifically used for: Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the first processing result; Based on the slow time period dimension, a Fourier transform is performed on the first processing result to obtain the second processing result; Based on the first type of phase difference, phase difference compensation is performed on the second processing result to obtain the target result.

4. The MIMO radar according to claim 1, characterized in that, The second switching mode includes: When each transmitting antenna is turned on, during the duration of transmitting a complete radar signal, the plurality of receiving antennas are turned on sequentially and receive radar echo signals of a portion of the radar signal transmitted by the transmitting antenna during the turn-on duration. The turn-on duration of each receiving antenna is the ratio of the duration to the number of the plurality of receiving antennas. After the plurality of receiving antennas are turned on sequentially, the radar signal is generated by the next transmitting antenna of the transmitting antenna, and so on in a cycle.

5. The MIMO radar according to claim 1 or 4, characterized in that, The radar signal processing module is specifically used for: Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the third processing result; Based on the second type of phase difference, phase difference compensation is performed on the third processing result to obtain the first compensation result; Based on the slow time period dimension, the first compensation result is subjected to Fourier transform to obtain the fourth processing result; Based on the first type of phase difference, phase difference compensation is performed on the fourth processing result to obtain the target result.

6. The MIMO radar according to claim 1, characterized in that, The radar signal processing module is also used for: The target result is analyzed to obtain the detection result of the detected target object; wherein the detection result includes at least one of speed, distance and angle.

7. A signal processing method, characterized in that, Applied to the MIMO radar according to any one of claims 1-6, the method comprises: Multiple transmitting antennas are switched sequentially. When switching to a transmitting antenna, that transmitting antenna is turned on so that it transmits radar signals. When each transmitting antenna is turned on, multiple receiving antennas are switched sequentially according to a specified switching mode among a preset multiple switching modes. When switching to a receiving antenna, that receiving antenna is turned on so that it receives the radar echo signal of the radar signal in the specified switching mode. The multiple switching modes include: a first switching mode that controls each receiving antenna to receive the radar echo signal of a complete radar signal, and a second switching mode that controls each receiving antenna to receive the radar echo signal of a portion of a complete radar signal. The multiple receiving antennas share a single receiving link and their operating timing does not overlap. If the specified switching mode is the first switching mode, then after switching the multiple transmitting antennas, the received radar echo signal is compensated for the phase difference based on the first type of phase difference caused by switching the multiple transmitting antennas, and the target result is obtained. If the specified switching mode is the second switching mode, then after switching the multiple transmitting antennas, phase difference compensation is performed on the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas and the second type of phase difference caused by switching the multiple receiving antennas, to obtain the target result.

8. The method according to claim 7, characterized in that, The first switching mode includes: When each transmitting antenna is turned on, each receiving antenna sequentially receives the radar echo signal of a complete radar signal transmitted by that transmitting antenna. After all the receiving antennas have received the radar echo signal, the next transmitting antenna of that transmitting antenna transmits the radar signal, and so on in a cycle.

9. The method according to claim 7 or 8, characterized in that, The step of compensating for the phase difference of the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas to obtain the target result includes: Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the first processing result; Based on the slow time period dimension, a Fourier transform is performed on the first processing result to obtain the second processing result; Based on the first type of phase difference, phase difference compensation is performed on the second processing result to obtain the target result.

10. The method according to claim 7, characterized in that, The second switching mode includes: When each transmitting antenna is turned on, during the duration of transmitting a complete radar signal, the plurality of receiving antennas are turned on sequentially and receive radar echo signals of a portion of the radar signal transmitted by the transmitting antenna during the turn-on duration. The turn-on duration of each receiving antenna is the ratio of the duration to the number of the plurality of receiving antennas. After the plurality of receiving antennas are turned on sequentially, the radar signal is generated by the next transmitting antenna of the transmitting antenna, and so on in a cycle.

11. The method according to claim 7 or 10, characterized in that, The phase difference compensation of the received radar echo signal based on the first type of phase difference caused by switching the multiple transmitting antennas and the second type of phase difference caused by switching the multiple receiving antennas, to obtain the target result, includes: Based on the fast time sampling point dimension, the received radar echo signal is subjected to Fourier transform to obtain the third processing result; Based on the second type of phase difference, phase difference compensation is performed on the third processing result to obtain the first compensation result; Based on the slow time period dimension, the first compensation result is subjected to Fourier transform to obtain the fourth processing result; Based on the first type of phase difference, phase difference compensation is performed on the fourth processing result to obtain the target result.

12. The method according to claim 7, characterized in that, The method further includes: The target result is analyzed to obtain the detection result of the detected target object; wherein the detection result includes at least one of speed, distance and angle.

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