Obstacle detection method and device

Abstract

This application relates to an obstacle detection method and device that obtains current detection data collected by each radar sensor within a target area on a vehicle based on the center frequency assigned at the current moment; determines the vehicle's obstacle detection status based on each current detection data; and then adjusts the frequency of each radar sensor based on the obstacle detection status to continuously detect obstacles around the vehicle. The frequency intervals corresponding to the center frequencies of two adjacent radar sensors may or may not overlap, and even in the case of overlap, the signal receiver can still correctly receive and interpret the radar sensor signals, thereby improving the accuracy of detecting the distance between the vehicle and surrounding obstacles.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to an obstacle detection method and device. Background Art

[0002] Radar sensors (such as ultrasonic radar) transmit high-frequency radar signals, receive reflected radar signals, and calculate distance by calculating the time difference between the round-trip signals. Radar sensors play a vital role in assisted parking scenarios. They provide accurate distance measurement, helping drivers better understand the distance between the vehicle and surrounding obstacles, thereby improving parking safety.

[0003] However, radar sensors are prone to co-frequency interference during operation. This is mainly caused by multiple radar sensors using the same or similar operating frequencies in the same environment. The signals emitted by multiple radar sensors overlap with each other, making it difficult for the receiving end to correctly receive and analyze the signals. As a result, there is a problem of low accuracy in the distance between the vehicle and surrounding obstacles determined based on radar signals. Summary of the Invention

[0004] Based on this, it is necessary to provide an obstacle detection method and device to address the above technical problems, which can improve the accuracy of detecting the distance between the vehicle and the surrounding obstacles.

[0005] In a first aspect, the present application provides an obstacle detection method, the method comprising:

[0006] Obtaining current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency assigned at the current moment;

[0007] Determining an obstacle detection status of the vehicle based on each current detection data;

[0008] According to the obstacle detection situation, the frequency of each radar sensor is adjusted to continuously detect obstacles around the vehicle;

[0009] The radar sensors are of the same type, and frequency constraints are satisfied between two adjacent radar sensors. The frequency constraints include whether frequency intervals corresponding to center frequencies of the two adjacent radar sensors overlap or do not overlap. If overlap exists, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval, and the two variable frequency center frequencies have opposite frequency change trends and different frequency change rates within the corresponding frequency interval, and the frequency change trend of the variable frequency center frequencies within the corresponding frequency interval is increasing or decreasing.

[0010] In one embodiment, the center frequency currently assigned to each radar sensor is selected from candidate center frequencies; wherein the number of candidate center frequencies is the same as the number of radar sensors deployed within the target external area, and the candidate center frequencies include a fixed frequency center frequency and a variable frequency center frequency.

[0011] In one embodiment, each candidate center frequency is determined by:

[0012] The operating frequency range of the radar sensor is divided to obtain at least two fixed-frequency center frequencies; wherein the frequency intervals corresponding to two adjacent fixed-frequency center frequencies do not overlap;

[0013] When the number of deployed radar sensors is greater than the number of frequencies of the fixed-frequency center frequency, determining a difference between the number of deployed radar sensors and the number of frequencies;

[0014] Adding the variable frequency center frequencies of the said difference value between adjacent fixed frequency center frequencies; wherein the frequency intervals corresponding to two adjacent variable frequency center frequencies do not overlap.

[0015] In one embodiment, adjusting the frequency of each radar sensor according to the obstacle detection situation includes:

[0016] determining a next frequency adjustment mode at a next moment according to the obstacle detection situation;

[0017] determining the center frequency of each radar sensor at a next moment according to consistency between the current frequency adjustment mode at the current moment and the next frequency adjustment mode;

[0018] Based on the center frequency of each radar sensor at the next moment, the frequency of each radar sensor is adjusted.

[0019] In one embodiment, determining the center frequency of each radar sensor at a next moment based on the consistency between the current frequency adjustment mode at the current moment and the next frequency adjustment mode includes:

[0020] If the current frequency adjustment mode at the current moment is consistent with the next frequency adjustment mode, determining the center frequency of each radar sensor at the next moment according to the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment;

[0021] If the current frequency adjustment mode at the current moment is inconsistent with the next frequency adjustment mode, the center frequency of each radar sensor at the next moment is determined according to the next frequency adjustment mode.

[0022] In one embodiment, determining the center frequency of each radar sensor at a next moment based on the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment includes:

[0023] If the current frequency adjustment mode is the obstacle-free mode, performing an inverse transformation on a frequency change trend of a frequency conversion center frequency in a corresponding frequency interval of the center frequency currently allocated to each radar sensor to obtain a new center frequency currently allocated to each radar sensor;

[0024] For each radar sensor, the center frequency newly allocated to the radar sensor at the current moment is used as the center frequency of the radar sensor corresponding to the next sensor number at the next moment;

[0025] The sensor numbers of two adjacent radar sensors are incremented, and the next sensor number after the last sensor number is the first sensor number.

[0026] In one embodiment, determining the center frequency of each radar sensor at a next moment based on the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment includes:

[0027] If the current frequency adjustment mode is the side-front obstacle mode, determining the center frequency of the first target radar sensor at a next moment based on the center frequency currently assigned to the first target radar sensor located in the side-front area of ​​the target external area, detection parameters corresponding to each candidate center frequency, and a frequency conversion rule; wherein the frequency conversion rule is such that the detection range corresponding to the center frequency of the first target radar sensor at the next moment is less than the detection range corresponding to the center frequency at the current moment;

[0028] determining, based on the detection parameter corresponding to the center frequency of the first target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency, a center frequency of a radar sensor adjacent to the first target radar sensor at the next moment;

[0029] With the goal of satisfying the frequency constraint condition between two adjacent radar sensors, the center frequencies at the next moment are allocated to the remaining radar sensors.

[0030] In one embodiment, determining the center frequency of a radar sensor adjacent to the first target radar sensor at the next moment based on the detection parameter corresponding to the center frequency of the first target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency includes:

[0031] determining a detection blind spot of the first target radar sensor based on detection parameters corresponding to the center frequency of the first target radar sensor at a next moment; wherein the detection parameters include a detection distance and a detection range;

[0032] Determine, based on the detection blind spot and detection parameters corresponding to each candidate center frequency, a center frequency of a radar sensor adjacent to the first target radar sensor at a next moment; wherein the detection parameters corresponding to the center frequency of the radar sensor adjacent to the first target radar sensor at the next moment can cover the detection blind spot.

[0033] In one embodiment, determining the center frequency of each radar sensor at a next moment based on the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment includes:

[0034] If the current frequency adjustment mode is the front obstacle mode, and the center frequency assigned to each second target radar sensor located in the front area of ​​the target external area at the current moment is the frequency conversion center frequency, then performing an inverse transformation on the frequency change trend of the frequency conversion center frequency of each second target radar sensor in the corresponding frequency interval, and alternately transforming the inversely transformed center frequencies of each second target radar sensor to obtain the center frequency of each second target radar sensor at the next moment;

[0035] allocating a maximum center frequency or a minimum center frequency at the next moment to radar sensors adjacent to the second target radar sensor based on the detection parameter corresponding to the center frequency of the second target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency;

[0036] With the goal of satisfying the frequency constraint condition between two adjacent radar sensors, the center frequencies at the next moment are allocated to the remaining radar sensors.

[0037] In one embodiment, determining a next frequency adjustment mode at a next moment according to the obstacle detection situation includes:

[0038] If the obstacle detection condition is that no obstacle is detected, determining that the next frequency adjustment mode at the next moment is the obstacle-free mode;

[0039] If the obstacle detection condition is that an obstacle is detected in front of the side of the target external area, determining the next frequency adjustment mode at the next moment to be the side-front obstacle mode;

[0040] If the obstacle detection condition is that an obstacle is detected right in front of the target external area, the next frequency adjustment mode at the next moment is determined to be the front obstacle mode.

[0041] In a second aspect, the present application further provides an obstacle detection device, comprising:

[0042] An acquisition module is used to obtain current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency allocated at the current moment;

[0043] A determination module, configured to determine an obstacle detection status of the vehicle based on each current detection data;

[0044] an adjustment module, configured to adjust the frequency of each radar sensor according to the obstacle detection situation, so as to continuously detect obstacles around the vehicle;

[0045] The radar sensors are of the same type, and frequency constraints are satisfied between two adjacent radar sensors. The frequency constraints include whether frequency intervals corresponding to center frequencies of the two adjacent radar sensors overlap or do not overlap. If overlap exists, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval, and the two variable frequency center frequencies have opposite frequency change trends and different frequency change rates within the corresponding frequency interval, and the frequency change trend of the variable frequency center frequencies within the corresponding frequency interval is increasing or decreasing.

[0046] In a third aspect, the present application further provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0047] Obtaining current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency assigned at the current moment;

[0048] Determining an obstacle detection status of the vehicle based on each current detection data;

[0049] According to the obstacle detection situation, the frequency of each radar sensor is adjusted to continuously detect obstacles around the vehicle;

[0050] The radar sensors are of the same type, and frequency constraints are satisfied between two adjacent radar sensors. The frequency constraints include whether frequency intervals corresponding to center frequencies of the two adjacent radar sensors overlap or do not overlap. If overlap exists, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval, and the two variable frequency center frequencies have opposite frequency change trends and different frequency change rates within the corresponding frequency interval, and the frequency change trend of the variable frequency center frequencies within the corresponding frequency interval is increasing or decreasing.

[0051] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the following steps:

[0052] Obtaining current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency assigned at the current moment;

[0053] Determining an obstacle detection status of the vehicle based on each current detection data;

[0054] According to the obstacle detection situation, the frequency of each radar sensor is adjusted to continuously detect obstacles around the vehicle;

[0055] The radar sensors are of the same type, and frequency constraints are satisfied between two adjacent radar sensors. The frequency constraints include whether frequency intervals corresponding to center frequencies of the two adjacent radar sensors overlap or do not overlap. If overlap exists, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval, and the two variable frequency center frequencies have opposite frequency change trends and different frequency change rates within the corresponding frequency interval, and the frequency change trend of the variable frequency center frequencies within the corresponding frequency interval is increasing or decreasing.

[0056] In a fifth aspect, the present application further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the following steps:

[0057] Obtaining current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency assigned at the current moment;

[0058] Determining an obstacle detection status of the vehicle based on each current detection data;

[0059] According to the obstacle detection situation, the frequency of each radar sensor is adjusted to continuously detect obstacles around the vehicle;

[0060] The radar sensors are of the same type, and frequency constraints are satisfied between two adjacent radar sensors. The frequency constraints include whether frequency intervals corresponding to center frequencies of the two adjacent radar sensors overlap or do not overlap. If overlap exists, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval, and the two variable frequency center frequencies have opposite frequency change trends and different frequency change rates within the corresponding frequency interval, and the frequency change trend of the variable frequency center frequencies within the corresponding frequency interval is increasing or decreasing.

[0061] The obstacle detection method and device described above acquire current detection data collected by each radar sensor within the target's external area on the vehicle based on the currently assigned center frequency. Based on each current detection data, the vehicle's obstacle detection status is determined. Furthermore, the frequency of each radar sensor is adjusted based on the obstacle detection status to continuously detect obstacles around the vehicle. If the radar sensors are of the same type, the frequency intervals corresponding to the center frequencies of two adjacent radar sensors may or may not overlap. If there is overlap, the center frequencies of the two adjacent radar sensors include a variable frequency center frequency and a fixed frequency center frequency, with the variable frequency center frequencies increasing or decreasing within the corresponding frequency interval. In this way, if the frequency intervals corresponding to the center frequencies of two adjacent radar sensors do not overlap, the problem of co-frequency resonance will not arise; even if the frequency intervals corresponding to the center frequencies of two adjacent radar sensors overlap, one of the center frequencies of the two adjacent radar sensors is a variable frequency center frequency and the other is a fixed frequency center frequency, and the variable frequency center frequency increases or decreases within the corresponding frequency interval, so that the waveforms of the variable frequency center frequency and the fixed frequency center frequency are different. Even if there is an intersection, the signal receiver can correctly receive and analyze the radar sensor signal based on the waveforms of the variable frequency center frequency and the fixed frequency center frequency, thereby improving the accuracy of detecting the distance between the vehicle and surrounding obstacles. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A diagram of an application environment of an obstacle detection method according to an embodiment;

[0063] Figure 2 1 is a flow chart of an obstacle detection method according to an embodiment;

[0064] Figure 3A FIG. 1 is a flow chart of determining candidate center frequencies in one embodiment;

[0065] Figure 3B Schematic diagram of the relationship between the fixed frequency center frequency, upper and lower limit frequencies in one embodiment;

[0066] Figure 4FIG1 is a schematic diagram of a process for adjusting the frequency of each radar sensor in one embodiment;

[0067] Figure 5 Schematic diagram of a flow chart for determining the center frequency of each radar sensor at the next moment in another embodiment;

[0068] Figure 6 FIG1 is a schematic diagram of the distribution of radar sensors within the same external area in one embodiment;

[0069] Figure 7 1 is a schematic diagram of a flow chart for determining the center frequency of each radar sensor at the next moment in another embodiment;

[0070] Figure 8 This is a schematic diagram of the detection range in one embodiment;

[0071] Figure 9 1 is a schematic diagram of a flow chart of determining the center frequency of a radar sensor adjacent to a first target radar sensor at a next moment in one embodiment;

[0072] Figure 10 A schematic diagram of determining the center frequency of each radar sensor at the next moment in yet another embodiment;

[0073] Figure 11 is a flow chart of an obstacle detection method according to another embodiment;

[0074] Figure 12 is a structural block diagram of an obstacle detection device in one embodiment;

[0075] Figure 13 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0076] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0077] The obstacle detection method provided in the embodiment of the present application can be applied to Figure 1 The application environment shown is specifically used in an application scenario of detecting the distance between a vehicle and an obstacle.

[0078] For example, a preset number of radar sensors of the same type may be deployed on the vehicle, for example, 12 radar sensors may be deployed. The radar sensors may be ultrasonic radar sensors, lidar sensors, or millimeter-wave radar sensors, etc. Of these, the 12 radar sensors may be deployed on the front bumper, with four sensors located on each of the left and right sides of the front bumper, and on the rear bumper, with four sensors located on each of the left and right sides of the rear bumper.

[0079] Among them, 12 radar sensors are connected to the Parking Distance Control (PDC) through a single line, and the data transmission and its port are the input / output interface (I / O) port (12-way lead) on the PDC. Then the PDC is connected to the domain controller through a twisted pair cable, and the data transmission and its port are the controller area network bus or the controller area network (Controller Area Network / CAN with Flexible Data-Rate, CAN / CAN FD) protocol to transmit data to the domain controller. The microcontroller unit (MCU) inside the domain controller analyzes the radar sensor echo signal data, and finally sends it to the system on chip (SOC) for algorithm fusion to determine the distance between the vehicle and the obstacle, and then adjust the center frequency of each radar sensor. The above method can be used by Figure 1 The SOC in the system is used for execution.

[0080] In one embodiment, Figure 2 As shown, an obstacle detection method is provided, which is applied to Figure 1 The SOC in the example is used to illustrate, including the following steps:

[0081] S201 , obtaining current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency allocated at the current moment.

[0082] For example, the target external area on the vehicle can be the front bumper area or the rear bumper area of ​​the vehicle. Current detection data collected by each radar sensor based on the currently assigned center frequency can be acquired via the CAN bus protocol. This current detection data can include data such as the radar signal's transmission time and transmission rate, which is used to determine the distance between the vehicle and the obstacle, as well as the obstacle's position relative to the vehicle.

[0083] The radar sensors are of the same type, and the frequency constraints between two adjacent radar sensors are met. The frequency constraints include whether the frequency intervals corresponding to the center frequencies of the two adjacent radar sensors overlap or do not overlap. In the event of overlap, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval, and the two variable frequency center frequencies have opposite frequency change trends and different frequency change rates within the corresponding frequency interval, and the frequency change trend of the variable frequency center frequencies within the corresponding frequency interval is increasing or decreasing. The fixed frequency center frequency transmits signals at a fixed frequency. This setting is to prevent radar sensors of the same type from using the same or similar center frequencies (operating frequencies) in the same environment or location, thereby avoiding the signals emitted by radar sensors using the same or similar center frequencies from overlapping each other, making it difficult for the receiving end to correctly receive and interpret the signals, thereby causing signal distortion, data loss, or communication interruption.

[0084] S202: Determine the obstacle detection status of the vehicle based on the current detection data.

[0085] Furthermore, the current detection data may include the distance and angle between the obstacle and the vehicle, and then the triangulation positioning method can be used to combine the distance and angle between the obstacle and the vehicle to determine the coordinates of the obstacle in the vehicle coordinate system, and then determine the area of ​​the vehicle where the obstacle is located, that is, determine the obstacle detection status of the vehicle.

[0086] S203: Adjust the frequency of each radar sensor according to the obstacle detection situation to continuously detect obstacles around the vehicle.

[0087] Furthermore, the frequency of each radar sensor can be adjusted according to the obstacle detection situation, that is, according to the area of ​​the vehicle where the obstacle is located, so as to adjust the detection distance and detection range of each radar sensor to continuously detect the movement trend of the obstacle, that is, to achieve continuous detection of obstacles around the vehicle.

[0088] The obstacle detection method acquires current detection data collected by each radar sensor within the target's external area on the vehicle based on the center frequency assigned at the current moment; determines the vehicle's obstacle detection status based on each current detection data; and then adjusts the frequency of each radar sensor based on the obstacle detection status to continuously detect obstacles around the vehicle. In this case, when the radar sensors are of the same type, the frequency intervals corresponding to the center frequencies of two adjacent radar sensors may overlap or not overlap. If there is overlap, the center frequencies of the two adjacent radar sensors may include one variable frequency center frequency and one fixed frequency center frequency, or may be two variable frequency center frequencies within the same frequency interval, with opposite frequency change trends and different frequency change rates within the corresponding frequency interval; and the variable frequency center frequencies may increase or decrease within the corresponding frequency interval. In this way, if the frequency intervals corresponding to the center frequencies of two adjacent radar sensors do not overlap, the problem of co-frequency resonance will not arise; even if the frequency intervals corresponding to the center frequencies of two adjacent radar sensors overlap, one of the center frequencies of the two adjacent radar sensors is a variable frequency center frequency and the other is a fixed frequency center frequency, and the variable frequency center frequency increases or decreases within the corresponding frequency interval, so that the waveforms of the variable frequency center frequency and the fixed frequency center frequency are different. Even if there is an intersection, the signal receiver can correctly receive and analyze the radar sensor signal based on the waveforms of the variable frequency center frequency and the fixed frequency center frequency; or in the case of two variable frequency center frequencies with the same frequency interval, the frequency change trends of the two variable frequency center frequencies within the corresponding frequency interval are opposite and the frequency change rates are different, so there will be no intersection, and the signal receiver can also correctly receive and analyze the radar sensor signal, thereby improving the accuracy of detecting the distance between the vehicle and surrounding obstacles.

[0089] In some optional implementations, the center frequency assigned to each radar sensor at the current moment in the above embodiment is selected from each candidate center frequency; wherein the number of each candidate center frequency is the same as the number of radar sensors deployed in the target external area, and each candidate center frequency includes a fixed frequency center frequency and a variable frequency center frequency.

[0090] In an embodiment of the present application, each candidate center frequency is determined in advance, so that the determined candidate center frequencies include a fixed-frequency center frequency and a variable-frequency center frequency, and the frequency intervals corresponding to the fixed-frequency center frequencies do not overlap, and the frequency intervals between the variable-frequency center frequencies do not overlap. The variable-frequency center frequency increases or decreases in the corresponding frequency interval. In this way, even if the frequency interval corresponding to the variable-frequency center frequency overlaps with the frequency interval corresponding to the fixed-frequency center frequency, since the signal waveforms of the fixed-frequency center frequency and the variable-frequency center frequency are different, the receiver can also distinguish between the signal of the fixed-frequency center frequency and the signal of the variable-frequency center frequency, thereby avoiding the problem of co-frequency interference, thereby improving the accuracy of detecting the distance between the obstacle and the vehicle.

[0091] Furthermore, the embodiment of the present application provides an achievable method for determining each candidate center frequency. Figure 3A , Figure 3A A flow chart of determining each candidate center frequency is provided, which specifically includes the following steps:

[0092] S301 : Divide the operating frequency range of the radar sensor to obtain at least two fixed-frequency center frequencies.

[0093] It should be noted that, taking an ultrasonic radar sensor as an example, the operating frequency range of the ultrasonic radar sensor is 20 kHz-150 kHz. The operating frequency range of the radar sensor is divided based on the non-overlapping frequency intervals corresponding to two adjacent fixed-frequency center frequencies, thereby obtaining at least two fixed-frequency center frequencies. For example, the obtained fixed-frequency center frequencies are 28 kHz, 58 kHz, and 126 kHz.

[0094] For example, a fixed-frequency center frequency can be randomly selected within the ultrasonic radar sensor's operating frequency range of 20 kHz to 150 kHz, for example, 28 kHz. The upper and lower frequency limits corresponding to the fixed-frequency center frequency can then be calculated based on the fixed-frequency center frequency, and the frequency range corresponding to the fixed-frequency center frequency can be determined based on the upper and lower frequency limits.

[0095] See also Figure 3B , Figure 3B A diagram showing the relationship between the fixed frequency center frequency, upper frequency limit, and lower frequency limit is provided. The upper frequency limit and lower frequency limit corresponding to the fixed frequency center frequency can be determined as follows:

[0096]

[0097] Among them, f m is the fixed frequency center frequency, f a is the upper limit frequency of the fixed frequency center frequency, f b The lower limit frequency of the fixed frequency center frequency. When determining the next fixed frequency center frequency, it is necessary to ensure that the frequency intervals corresponding to the lower limit frequency and the upper limit frequency of the next fixed frequency center frequency do not overlap with the frequency intervals corresponding to the lower limit frequency and the upper limit frequency of the previous fixed frequency center frequency.

[0098] Referring to Table 1, Table 1 provides a schematic diagram of frequency intervals of the determined fixed-frequency center frequencies, such that the frequency intervals of the determined fixed-frequency center frequencies do not overlap.

[0099] Table 1:

[0100] <![CDATA[Center frequency f m > <![CDATA[Upper frequency limit f a > <![CDATA[Lower frequency limit f b > 28 37 19 58 75 41 126 163 89

[0101] S302 : When the number of deployed radar sensors is greater than the number of frequencies of the fixed-frequency center frequency, determine a difference between the number of deployed radar sensors and the number of frequencies.

[0102] For example, if three or fewer radar sensors are deployed on the front bumper of a vehicle, the fixed-frequency center frequencies may be selected from 28 kHz, 58 kHz, and 126 kHz. If the number of deployed radar sensors is greater than the number of frequencies corresponding to the fixed-frequency center frequencies, for example, if the number of deployed radar sensors is six, the difference between the number of deployed radar sensors and the number of frequencies is first determined, for example, the determined difference is 3.

[0103] S303: Adding a number of variable frequency center frequencies equal to the difference between adjacent fixed frequency center frequencies.

[0104] Furthermore, a number of variable frequency center frequencies of a difference value may be added between adjacent fixed frequency center frequencies, for example, three variable frequency center frequencies may be added, wherein the frequency intervals corresponding to two adjacent variable frequency center frequencies do not overlap. For example, the three determined variable frequency center frequencies are 40±5 kHz, 68±5 kHz, and 86±5 kHz.

[0105] Table 2:

[0106]

[0107] For example, see Table 2, which provides a frequency range diagram of a center frequency. The frequency ranges of the fixed-frequency center frequencies do not overlap, and the frequency ranges of the variable-frequency center frequencies do not overlap either. Each center frequency is replaced by a letter in sequence, with the number 0 after the letter representing the fixed-frequency center frequency, and the numbers 1 and 2 after the letter representing the variable-frequency center frequency. 1 represents an increase in the variable-frequency center frequency within the corresponding frequency range, and 2 represents a decrease in the variable-frequency center frequency within the corresponding frequency range.

[0108] It should be noted that embodiments of the present application can utilize the physical properties of the ceramic pressing plate in a radar transducer to indirectly control the piezoelectric frequency generated by the transducer by controlling the voltage and current, thereby designing radar sensors with different center frequencies and bandwidths. Radar sensors can be designed based on center frequency and bandwidth to ensure that the upper and lower frequency limits do not overlap, thus avoiding co-channel interference.

[0109] In the embodiment of the present application, by determining each fixed-frequency center frequency with non-overlapping frequency intervals and each variable-frequency center frequency with non-overlapping frequency intervals, it is convenient to avoid the problem of co-frequency interference when setting the center frequency of each radar sensor.

[0110] In some optional implementations, the embodiments of the present application can automatically adjust the center frequency of each radar sensor according to the detection situation of the obstacle to achieve continuous detection of the obstacle.

[0111] See also Figure 4 , Figure 4 A schematic diagram of a process for adjusting the frequency of each radar sensor is provided, which specifically includes the following steps:

[0112] S401: Determine the next frequency adjustment mode at the next moment according to the obstacle detection situation.

[0113] For example, the target external area of ​​the vehicle can be pre-divided into the side front and the front, and a correspondence between obstacle detection conditions and frequency adjustment modes can be established. Based on the obstacle detection conditions, the next frequency adjustment mode corresponding to the next obstacle detection condition can be determined from the pre-established correspondence.

[0114] For example, the relationship between the pre-established obstacle detection conditions and the frequency adjustment mode may be as follows:

[0115] If the obstacle detection condition is that no obstacle is detected, the corresponding frequency adjustment mode is the obstacle-free mode. Therefore, based on the obstacle detection condition, the next frequency adjustment mode determined at the next moment is the obstacle-free mode.

[0116] If the obstacle detection situation is that the obstacle is detected in front of the side of the target external area, the corresponding frequency adjustment mode is the side front obstacle mode. Therefore, based on the obstacle detection situation, the next frequency adjustment mode determined at the next moment is the side front obstacle mode.

[0117] If the obstacle detection situation is that the obstacle is detected in front of the target external area, the corresponding frequency adjustment mode is the obstacle mode in front. Therefore, based on the obstacle detection situation, the next frequency adjustment mode determined at the next moment is the obstacle mode in front.

[0118] In an embodiment of the present application, by pre-establishing a correspondence between the obstacle detection situation and the frequency adjustment mode, it is possible to switch to the frequency adjustment mode at the next moment based on the obstacle detection situation at the current moment, and to automatically adjust the center frequency of each radar sensor according to the obstacle detection situation, thereby achieving continuous detection of obstacles.

[0119] S402 : Determine the center frequency of each radar sensor at the next moment according to the consistency between the current frequency adjustment mode at the current moment and the next frequency adjustment mode.

[0120] Furthermore, the center frequency of each radar sensor at the next moment can be determined based on the consistency between the current frequency adjustment mode and the next frequency adjustment mode. For example, if the current frequency adjustment mode and the next frequency adjustment mode are consistent, such as both being the no-obstacle mode, the center frequency of each radar sensor at the next moment can be determined based on the no-obstacle mode and the center frequency of each radar sensor at the current moment. If the current frequency adjustment mode and the next frequency adjustment mode are inconsistent, such as if the current frequency adjustment mode is the no-obstacle mode and the next frequency adjustment mode is the side-front obstacle mode, the center frequency of each radar sensor at the next moment will be the center frequency of each radar sensor at the initial moment in the side-front obstacle mode.

[0121] S403 , adjusting the frequency of each radar sensor based on the center frequency of each radar sensor at the next moment.

[0122] Furthermore, the frequency of each radar sensor can be adjusted based on the center frequency of each radar sensor at the next moment, and each radar sensor can be used to continuously detect obstacles.

[0123] In an embodiment of the present application, by comparing whether the current frequency adjustment mode is consistent with the next frequency adjustment mode, the center frequency of each radar sensor at the next moment is determined, thereby achieving automatic switching of the center frequency of each radar sensor, thereby achieving continuous detection of obstacles.

[0124] Furthermore, in the above embodiment, S402 determines the center frequency of each radar sensor at the next moment based on the consistency between the current frequency adjustment mode at the current moment and the next frequency adjustment mode, which can be specifically achieved by the following method:

[0125] If the current frequency adjustment mode and the next frequency adjustment mode are the same at the current moment, the center frequency of each radar sensor at the next moment is determined based on the current frequency adjustment mode and the center frequency assigned to each radar sensor at the current moment. It should be noted that the center frequency corresponding to each radar sensor at each moment in each frequency adjustment cycle under each frequency adjustment mode can be pre-established. If the frequency adjustment mode remains unchanged, the center frequency of each radar sensor at the next moment can be determined based on the center frequency corresponding to each radar sensor at each moment in each frequency adjustment cycle under the frequency adjustment mode and the center frequency assigned to each radar sensor at the current moment.

[0126] If the current frequency adjustment mode at the current moment is inconsistent with the next frequency adjustment mode, the center frequency of each radar sensor at the next moment is determined according to the next frequency adjustment mode.

[0127] For example, if the current frequency adjustment mode at the current moment is inconsistent with the next frequency adjustment mode, the center frequency of each radar sensor at the next moment can be determined based on the next frequency adjustment mode. Thus, the center frequency corresponding to each radar sensor at each moment in each frequency adjustment cycle under each frequency adjustment mode is pre-established. If the current frequency adjustment mode at the current moment is inconsistent with the next frequency adjustment mode, the center frequency corresponding to each radar sensor at the initial moment in the frequency adjustment cycle under the next frequency adjustment mode can be used as the center frequency of each radar sensor at the next moment.

[0128] In an embodiment of the present application, a feasible method for determining the center frequency of each radar sensor at the next moment based on the consistency between the current frequency adjustment mode at the current moment and the next frequency adjustment mode is provided, thereby automatically adjusting the center frequency of each radar sensor according to the obstacle detection situation to achieve the purpose of continuous detection of obstacles.

[0129] In some optional implementations, the embodiments of the present application provide an implementable method for determining the center frequency of each radar sensor at the next moment when the current frequency adjustment mode and the next frequency adjustment mode are consistent and in an obstacle-free mode.

[0130] For example, see Figure 5 , Figure 5 A schematic diagram of another process for determining the center frequency of each radar sensor at the next moment is provided, which specifically includes the following steps:

[0131] S501: If the current frequency adjustment mode is the obstacle-free mode, the frequency change trend of the frequency conversion center frequency in the corresponding frequency range of the center frequency allocated to each radar sensor at the current moment is reversed to obtain a new center frequency allocated to each radar sensor at the current moment.

[0132] It should be noted that the center frequency assigned to each radar sensor at the current moment can include a fixed-frequency center frequency or a variable-frequency center frequency. Since the variable-frequency center frequency has two frequency change trends in the corresponding frequency range, namely increasing or decreasing, which can also be understood as upsweep and downsweep. If the same variable-frequency center frequency with the same change trend is emitted by the same or adjacent radar sensors at adjacent moments, it is likely to cause signal overlap, making it difficult for the receiver to correctly receive and analyze the echo signal. To avoid this problem, it is necessary to perform an inverse transformation on the frequency change trend of the variable-frequency center frequency in the corresponding frequency range assigned to each radar sensor at the current moment, that is, to transform the increasing trend into the decreasing trend, or to transform the decreasing trend into the increasing trend, so as to obtain the new center frequency assigned to each radar sensor at the current moment.

[0133] S502 : For each radar sensor, use the new center frequency allocated to the radar sensor at the current moment as the center frequency of the radar sensor corresponding to the next sensor number at the next moment.

[0134] Furthermore, a sensor serial number can be assigned to each radar sensor located in the same external area. For example, if six radar sensors are deployed in the front bumper area of ​​a vehicle, the six radar sensors are numbered and the areas where the radar sensors are located are divided.

[0135] For example, see Figure 6 , Figure 6 This diagram shows the distribution of radar sensors within the same target's exterior area. The exterior area is divided into Area 1, Area 2, and Area 3, corresponding to the left front, front, and right front, respectively. The left and right fronts are considered the side front. Sensors numbered 1 and 2 are located in the left front of the side front, sensors numbered 3 and 4 are located in the front, and sensors numbered 5 and 6 are located in the right front of the side front.

[0136] Optionally, for each radar sensor, the newly assigned center frequency at the current moment is used as the center frequency of the radar sensor corresponding to the next sensor number at the next moment. The sensor numbers of two adjacent radar sensors are incremented, and the sensor number next to the last sensor number is the first sensor number.

[0137] For example, in Figure 6 On this basis, an embodiment of the present application provides a pre-established center frequency corresponding to each radar sensor at each moment in a frequency adjustment cycle in the obstacle-free mode, and takes an example in which a frequency adjustment cycle in the obstacle-free mode includes 6 moments.

[0138] The six radar sensors are represented by sensor1, sensor2, sensor3, sensor4, sensor5, and sensor6. The center frequency of each radar sensor at each moment in a frequency adjustment cycle is as follows:

[0139] T1: (sensor1=A0)(sensor2=B1)(sensor3=C0)(sensor4=D2)(sensor5=E1)(sensor6=F0);

[0140] T2: (sensor1=F0)(sensor2=A0)(sensor3=B2)(sensor4=C0)(sensor5=D1)(sensor6=E2);

[0141] T3: (sensor1=E1)(sensor2=F0)(sensor3=A0)(sensor4=B1)(sensor5=C0)(sensor6=D2);

[0142] T4: (sensor1=D1)(sensor2=E2)(sensor3=F0)(sensor4=A0)(sensor5=B1)(sensor6=C0);

[0143] T5: (sensor1=C0)(sensor2=D2)(sensor3=E1)(sensor4=F0)(sensor5=A0)(sensor6=B2);

[0144] T6: (sensor1=B1) (sensor2=C0) (sensor3=D1) (sensor4=E2) (sensor5=F0) (sensor6=A0).

[0145] It should be noted that each moment within a frequency adjustment cycle can be used as the current moment. The center frequency corresponding to each radar sensor at each moment within a frequency adjustment cycle in obstacle-free mode and the current moment can be used to determine the center frequency corresponding to each radar sensor at the next moment.

[0146] In an embodiment of the present application, a feasible method is provided for automatically switching the center frequency of each radar sensor at the next moment when the current frequency adjustment mode and the next frequency adjustment mode are consistent and in the obstacle-free mode, thereby achieving continuous detection of obstacles.

[0147] In some optional implementations, an embodiment of the present application provides an implementable method for determining the center frequency of each radar sensor at the next moment when the current frequency adjustment mode and the next frequency adjustment mode are consistent and the center frequency of each radar sensor is in the side front obstacle mode.

[0148] For example, see Figure 7 , Figure 7 A schematic diagram of another process for determining the center frequency of each radar sensor at the next moment is provided, which specifically includes the following steps:

[0149] S701: If the current frequency adjustment mode is the side-front obstacle mode, determine the center frequency of the first target radar sensor at the next moment based on the center frequency currently assigned to the first target radar sensor located in the side-front area within the target external area, the detection parameters corresponding to each candidate center frequency, and the frequency conversion rule.

[0150] For example, the embodiment of the present application is also based on Figure 6 Taking the radar sensors shown as an example, radar sensor numbered 2 is used as the first target radar sensor. If the current frequency adjustment mode is the side-front obstacle mode, the center frequency of the first target radar sensor at the next moment is determined based on the center frequency currently assigned to the first target radar sensor located in the side-front area of ​​the target outer area, the detection parameters corresponding to each candidate center frequency, and the frequency conversion rule. The frequency conversion rule stipulates that the detection range corresponding to the center frequency of the first target radar sensor at the next moment is smaller than the detection range corresponding to the center frequency at the current moment. It can be understood that this configuration ensures that the detection range of the first target radar sensor changes from far to near within the same frequency adjustment cycle, thereby detecting whether obstacles are approaching the vehicle.

[0151] S702 : Determine a center frequency of a radar sensor adjacent to the first target radar sensor at the next moment based on a detection parameter corresponding to the center frequency of the first target radar sensor at the next moment and detection parameters corresponding to each candidate center frequency.

[0152] It should be noted that the larger the center frequency, the longer the corresponding detection distance and the smaller the detection range (Field of View, FOV). Figure 8 , Figure 8 A detection range diagram is provided. The FOVs of the radar sensors need to overlap to achieve full coverage of the area outside the target and monitor the movement trend and direction of obstacles in the area outside the target.

[0153] Since the detection distance of the first target radar sensor changes from far to near in the same frequency adjustment period, the detection range increases from small to large. When the detection distance of the first target radar sensor is large, the radar sensors adjacent to the first target radar sensor need to make up for the detection range of the first target radar sensor; and when the detection range of the first target radar sensor is large, the radar sensors adjacent to the first target radar sensor need to make up for the detection distance of the first target radar sensor, so that the radar sensor can detect the movement trend of obstacles in the entire target external area.

[0154] Based on this, the detection parameters corresponding to the center frequency of the first target radar sensor at the next moment may include a detection distance and a detection range. The center frequency of the radar sensor adjacent to the first target radar sensor at the next moment can be determined based on the detection parameters corresponding to the center frequency of the first target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency, so that the radar sensors adjacent to the first target radar sensor can make up for the detection distance or detection range of the first target sensor at the next moment; for example, the center frequencies of the radar sensors numbered 1 and 3 at the next moment can be set to make up for the detection distance or detection range of the first target sensor.

[0155] S703 , with the goal of satisfying the frequency constraint condition between two adjacent radar sensors, allocate the center frequencies at the next moment to the remaining radar sensors.

[0156] For example, when allocating the center frequencies of the remaining radar sensors at the next moment, the goal can be to satisfy the frequency constraint conditions between two adjacent radar sensors, so as to avoid co-frequency interference with the center frequencies of the already allocated radar sensors when allocating the center frequencies of the remaining radar sensors at the next moment; on this basis, the remaining radar sensors located at the outermost end of the target external area can be allocated center frequencies with longer detection distances to detect whether there are new obstacles approaching the outermost end of the target external area.

[0157] In an embodiment of the present application, a feasible method is provided for automatically switching the center frequency of each radar sensor at the next moment when the current frequency adjustment mode and the next frequency adjustment mode are consistent and in the side front obstacle mode, thereby achieving continuous detection of obstacles.

[0158] Furthermore, the present application embodiment provides a specific implementation method of S702 in the above embodiment, see Figure 9 , Figure 9 A schematic flow chart of determining the center frequency of a radar sensor adjacent to a first target radar sensor at a next moment is provided, specifically comprising the following steps:

[0159] S901 : Determine a detection blind spot of the first target radar sensor according to a detection parameter corresponding to a center frequency of the first target radar sensor at a next moment.

[0160] For example, the detection parameters may include a detection distance and a detection range. Based on the detection distance and detection range corresponding to the center frequency of the first target radar sensor at the next moment, as well as the range of the lateral front area within the target external area, the detection blind spot of the first target radar sensor, i.e., the range that cannot be detected by the first target radar sensor, can be determined.

[0161] S902 : Determine the center frequency of a radar sensor adjacent to the first target radar sensor at a next moment based on the detection blind area and detection parameters corresponding to each candidate center frequency.

[0162] Furthermore, the center frequency of the radar sensor adjacent to the first target radar sensor at the next moment can be determined based on the detection blind spot and the detection parameters corresponding to each candidate center frequency, so that the detection parameters corresponding to the center frequency of the radar sensor adjacent to the first target radar sensor at the next moment can cover the detection blind spot.

[0163] In an embodiment of the present application, by setting the center frequency of a radar sensor adjacent to the first target radar sensor located in the side front area at the next moment, the detection range and distance of the first target radar sensor are compensated, thereby avoiding the detection range of the first target radar sensor not being able to cover the entire side front area, thereby accurately detecting the movement trend and direction of the obstacle.

[0164] For example, in Figure 6 On this basis, an embodiment of the present application provides a pre-established center frequency corresponding to each radar sensor at each moment in a frequency adjustment cycle in the side front obstacle mode, and takes an example in which a frequency adjustment cycle in the obstacle-free mode includes 3 moments.

[0165] When the front side is the left front, the center frequencies of the radar sensors at each moment in a frequency adjustment cycle are as follows:

[0166] T1: (sensor1=E2)(sensor2=F0)(sensor3=D2)(sensor4=E1)(sensor5=A0)(sensor6=F0);

[0167] T2: (sensor1=E1)(sensor2=C0)(sensor3=D1)(sensor4=E2)(sensor5=B1)(sensor6=D2);

[0168] T3: (sensor1=D2) (sensor2=B2) (sensor3=B1) (sensor4=A0) (sensor5=B2) (sensor6=D1).

[0169] In this mode, when an obstacle appears in the left front, the center frequency of sensor2 at time T1 is selected as F0, which has the longest detection distance, but the detection range is small. Therefore, the center frequencies of sensor1 and sensor3 are selected as E2 and D2, which can make up for the detection range of sensor2; and E2 and D2 are decreasing, and the detection distance is from far to near. If it is a moving obstacle, the direction of the obstacle's movement can be monitored.

[0170] At time T2, the center frequency of sensor 1 is E1, and it detects from near to far. Sensor 1 is installed on the left side of the front guard, and has a large angle deviation from sensor 2 adjacent to the front side. Therefore, it can predict whether the obstacle is moving to the left and close to sensor 1. The center frequencies of sensor 2 and sensor 3 are C0 and D1 respectively. The installation angle deviation between the two is small, and they can also achieve continuous monitoring of whether the obstacle is stationary or moving, and continuously monitor the direction of the obstacle's movement.

[0171] At time T3, the detection distance of sensor2 continues to decrease, and the center frequencies of sensor1 and sensor3 are selected as D2 and B1 to compensate for the detection distance and detection range of sensor2, so as to continuously monitor whether the obstacle is stationary or moving, and continuously monitor the direction of the obstacle's movement.

[0172] When the front side is the right front, the center frequencies corresponding to the radar sensors numbered 6, 5, and 4 at each moment in one frequency adjustment cycle are adjusted in the same manner as the center frequencies corresponding to the radar sensors numbered 1, 2, and 3 when the front side is the left front; the center frequencies corresponding to the radar sensors numbered 1, 2, and 3 are adjusted in the same manner as the center frequencies corresponding to the radar sensors numbered 6, 5, and 4 when the front side is the left front.

[0173] When the front side is the right front, the center frequencies of the radar sensors at each moment in a frequency adjustment cycle are as follows:

[0174] T1: (sensor6=E2)(sensor5=F0)(sensor4=D2)(sensor3=E1)(sensor2=A0)(sensor1=F0);

[0175] T2: (sensor6=E1)(sensor5=C0)(sensor4=D1)(sensor3=E2)(sensor2=B1)(sensor1=D2);

[0176] T3: (sensor6=D2) (sensor5=B2) (sensor4=B1) (sensor3=A0) (sensor2=B2) (sensor1=D1).

[0177] The rule followed by the center frequency corresponding to each radar sensor at each moment in a frequency adjustment cycle is similar to that in the case where the front side is the right front, and will not be repeated here.

[0178] In some optional implementations, an embodiment of the present application provides an implementable method for determining the center frequency of each radar sensor at the next moment when the current frequency adjustment mode and the next frequency adjustment mode are consistent and the obstacle ahead mode is in progress.

[0179] For example, see Figure 10 , Figure 10 A schematic diagram of another process for determining the center frequency of each radar sensor at the next moment is provided, which specifically includes the following steps:

[0180] S1001: If the current frequency adjustment mode is the front obstacle mode, and the center frequency assigned to each second target radar sensor located in the front area of ​​the target external area at the current moment is a variable frequency center frequency, then an inverse transformation is performed on the frequency change trend of the variable frequency center frequency of each second target radar sensor in the corresponding frequency range, and the inversely transformed center frequency of each second target radar sensor is alternately transformed to obtain the center frequency of each second target radar sensor at the next moment.

[0181] For example, taking the case where the radar sensors deployed in the area directly in front of the target external area include at least two, for example, Figure 6 Sensor 3 and sensor 4 are used as second target radar sensors located in the front area of ​​the target external area.

[0182] If the current frequency adjustment mode is the forward obstacle mode, and the center frequency assigned to each second target radar sensor located in the forward area of ​​the target outer area at the current moment is a variable frequency center frequency, then to prevent unreceived echo signals from the previous moment from being interfered with by the sensor signal transmitted at the next moment, the frequency variation trend of the variable frequency center frequency of each second target radar sensor within the corresponding frequency range needs to be inversely transformed. For example, the frequency variation trend of the variable frequency center frequency of each second target radar sensor within the corresponding frequency range can be transformed from increasing to decreasing, or from decreasing to increasing. The inversely transformed center frequencies of each second target radar sensor are then alternately transformed to obtain the center frequency of each second target radar sensor at the next moment.

[0183] For example, if the center frequencies of sensor3 and sensor4 at the previous moment are E2 and D1 respectively, then the center frequencies of sensor3 and sensor4 at the next moment will be D2 and E1 respectively.

[0184] S1002 : Allocate a maximum center frequency or a minimum center frequency at the next moment to radar sensors adjacent to the second target radar sensor based on the detection parameters corresponding to the center frequency of the second target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency.

[0185] For example, in order to predict whether an obstacle has a tendency to move to the left or right, the maximum center frequency or the minimum center frequency can be assigned to the radar sensor adjacent to the second target radar sensor at the next moment based on the detection parameters corresponding to the center frequency of the second target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency.

[0186] Optionally, when predicting whether the obstacle has a tendency to move to the left, the maximum center frequency can be allocated to the radar sensor sensor2 adjacent to the second target radar sensor at the next moment, and the minimum center frequency can be allocated to the radar sensor sensor5 adjacent to the second target radar sensor at the next moment, so as to use sensor2 to detect whether the obstacle has a tendency to move to the left, and use sensor5 to make up for the detection range of sensor4.

[0187] When predicting whether the obstacle has a tendency to move to the right, the maximum center frequency can be allocated to the radar sensor sensor5 adjacent to the second target radar sensor at the next moment, and the minimum center frequency can be allocated to the radar sensor sensor2 adjacent to the second target radar sensor at the next moment, so as to use sensor5 to detect whether the obstacle has a tendency to move to the right, and use sensor2 to make up for the detection range of sensor3.

[0188] S1003 , with the goal of satisfying the frequency constraint condition between two adjacent radar sensors, allocate the center frequencies at the next moment to the remaining radar sensors.

[0189] For example, when assigning the next center frequency to the remaining radar sensors, sensor1 and sensor6, the goal is to ensure that the frequency constraints between two adjacent radar sensors are met, and to avoid co-channel interference between the center frequencies of radar sensors sensor1 and sensor6 and the already assigned center frequencies. For example, while ensuring that the center frequencies of radar sensors sensor1 and sensor6 do not interfere with the already assigned center frequencies, a larger center frequency can be assigned to sensor1 and sensor6 as much as possible to increase the detection range of the radar sensors on both sides of the target area, thereby promptly detecting whether there are obstacles on both sides of the target area.

[0190] For example, when the side front is the front, the center frequency corresponding to each radar sensor at each moment in a frequency adjustment cycle is as follows:

[0191] T1: (sensor1=B1)(sensor2=A0)(sensor3=E2)(sensor4=D1)(sensor5=F0)(sensor6=B1);

[0192] T2: (sensor1=B2)(sensor2=F0)(sensor3=D2)(sensor4=E1)(sensor5=A0)(sensor6=B2);

[0193] T3: (sensor1=B1)(sensor2=A0)(sensor3=E2)(sensor4=D1)(sensor5=F0)(sensor6=B1);

[0194] T4: (sensor1=B2) (sensor2=F0) (sensor3=D2) (sensor4=E1) (sensor5=A0) (sensor6=B2).

[0195] First, sensor3 and sensor4 are set to E2 and D1 frequencies, and then they are exchanged to D1 and E2 frequencies. After obtaining the direct echo distance and the indirect echo distance, the coordinates of the detected obstacle under the vehicle coordinate axis are solved based on triangulation positioning, and the approximate direction of the obstacle can be known.

[0196] Sensor5 at time T1 and sensor2 at time T2 are set to F0, with the longest detection distance. This is the threshold value for distinguishing the left and right movement trend of obstacles. When the obstacle has a left and right movement trend, sensor5 and sensor2 will be triggered, and the echo signal will be received, and then the side and front obstacle mode will be switched.

[0197] Because the safety mechanism requires repeated checks to further determine whether the obstacle is moving, and if it is a moving obstacle, it can continuously track the direction of movement. In this way, the entire area directly ahead can be scanned and the position of the obstacle relative to the vehicle can be calculated.

[0198] In an embodiment of the present application, by setting the center frequency of the second target radar sensor located in the area directly ahead, it is possible to detect whether an obstacle has a tendency to approach the vehicle; and by setting the center frequency of the radar sensor adjacent to the second target radar sensor located in the area directly ahead at the next moment, it is possible to detect whether the obstacle has a tendency to move to the left or right, thereby accurately detecting the movement trend and direction of the obstacle.

[0199] It should be noted that if an obstacle appears in at least two of the forward, left, and right forward areas, the center frequencies assigned to the radar sensors in each area at each moment can be based on satisfying the frequency constraints between adjacent radar sensors. Specifically, the center frequencies assigned to the radar sensors in each area at each moment can be based on the principle that the detection range of the radar sensors in each area gradually decreases, while the center frequencies of adjacent radar sensors compensate for their detection range, without causing co-frequency interference. This allows for continuous detection of the movement and direction of obstacles.

[0200] It should be noted that the detection data detected by each radar sensor in various frequency adjustment modes in the above embodiments can be combined with data collected by other sensors to detect obstacles more accurately, which helps to enhance the diversity of conditions for intelligent driving algorithm design and functional scenario judgment.

[0201] In some optional implementations, see Figure 11 , Figure 11 A flowchart of another obstacle detection method is provided, which specifically includes the following steps:

[0202] S1101, obtaining current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency allocated at the current moment.

[0203] S1102: Determine the obstacle detection status of the vehicle based on the current detection data.

[0204] S1103: Determine the next frequency adjustment mode at the next moment according to the obstacle detection situation.

[0205] S1104 : Determine the center frequency of each radar sensor at the next moment based on the consistency between the current frequency adjustment mode at the current moment and the next frequency adjustment mode.

[0206] S1105 : Based on the center frequency of each radar sensor at the next moment, adjust the frequency of each radar sensor to continuously detect obstacles around the vehicle.

[0207] In intelligent driving, the ultrasonic radar system needs multiple cycles to transmit signals in a round-trip manner to detect the entire environment around the vehicle body. The round-trip mode is complex to design, and it is impossible for all ultrasonic radar systems to work at the same time. The cycle of scanning the entire environment is long and the timeliness is low.

[0208] The obstacle detection method provided by the embodiments of this application enables radar sensors to operate simultaneously at all times, without considering the interval between groups or the cycle change time. This allows each radar sensor to switch its center frequency without delay according to the actual scenario. Furthermore, by setting different candidate center frequencies, co-channel interference can be avoided even if the radar sensors' FOVs overlap.

[0209] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0210] Based on the same inventive concept, embodiments of the present application further provide an obstacle detection device for implementing the aforementioned obstacle detection method. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more obstacle detection device embodiments provided below can be found in the above-described limitations of the obstacle detection method and will not be further elaborated here.

[0211] In one embodiment, Figure 12 As shown, an obstacle detection device is provided, comprising:

[0212] An acquisition module 10 is configured to acquire current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency allocated at the current moment;

[0213] A determination module 20 is used to determine the obstacle detection status of the vehicle based on each current detection data;

[0214] An adjustment module 30 is used to adjust the frequency of each radar sensor according to the obstacle detection situation to continuously detect obstacles around the vehicle;

[0215] The radar sensors are of the same type, and frequency constraints are satisfied between two adjacent radar sensors. The frequency constraints include whether frequency intervals corresponding to the center frequencies of the two adjacent radar sensors overlap or do not overlap. In the event of overlap, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval, and the frequency change trends of the two variable frequency center frequencies within the corresponding frequency interval are opposite and the frequency change rates are different, and the frequency change trends of the variable frequency center frequencies within the corresponding frequency interval are increasing or decreasing.

[0216] In one embodiment, the center frequency currently assigned to each radar sensor is selected from candidate center frequencies; wherein the number of candidate center frequencies is the same as the number of radar sensors deployed within the target external area, and the candidate center frequencies include a fixed frequency center frequency and a variable frequency center frequency.

[0217] The obstacle detection device acquires current detection data collected by each radar sensor within the target area on the vehicle based on the currently assigned center frequency. Based on the current detection data, it determines the vehicle's obstacle detection status. Furthermore, based on the obstacle detection status, it adjusts the frequency of each radar sensor to continuously detect obstacles around the vehicle. If the radar sensors are of the same type, the frequency intervals corresponding to the center frequencies of two adjacent radar sensors may or may not overlap. If there is overlap, the center frequencies of the two adjacent radar sensors include a variable frequency center frequency and a fixed frequency center frequency, with the variable frequency center frequencies increasing or decreasing within the corresponding frequency interval. In this way, if the frequency intervals corresponding to the center frequencies of two adjacent radar sensors do not overlap, the problem of co-frequency resonance will not arise; even if the frequency intervals corresponding to the center frequencies of two adjacent radar sensors overlap, one of the center frequencies of the two adjacent radar sensors is a variable frequency center frequency and the other is a fixed frequency center frequency, and the variable frequency center frequency increases or decreases within the corresponding frequency interval, so that the waveforms of the variable frequency center frequency and the fixed frequency center frequency are different. Even if there is an intersection, the signal receiver can correctly receive and analyze the radar sensor signal based on the waveforms of the variable frequency center frequency and the fixed frequency center frequency; or in the case of two variable frequency center frequencies with the same frequency interval, the frequency change trends of the two variable frequency center frequencies within the corresponding frequency interval are opposite and the frequency change rates are different, so there will be no intersection, and the signal receiver can also correctly receive and analyze the radar sensor signal, thereby improving the accuracy of detecting the distance between the vehicle and surrounding obstacles.

[0218] In one embodiment, the determination module 20 is further configured to:

[0219] The operating frequency range of the radar sensor is divided to obtain at least two fixed-frequency center frequencies; wherein the frequency intervals corresponding to the two adjacent fixed-frequency center frequencies do not overlap; when the number of deployed radar sensors is greater than the number of frequencies of the fixed-frequency center frequencies, the difference between the number of deployed radar sensors and the number of frequencies is determined; and variable-frequency center frequencies by the number of the difference are added between adjacent fixed-frequency center frequencies; wherein the frequency intervals corresponding to the two adjacent variable-frequency center frequencies do not overlap.

[0220] In one embodiment, the adjustment module 30 specifically includes:

[0221] A first determining unit, configured to determine a next frequency adjustment mode at a next moment according to an obstacle detection situation;

[0222] a second determining unit, configured to determine the center frequency of each radar sensor at a next moment according to consistency between the current frequency adjustment mode at a current moment and the next frequency adjustment mode;

[0223] The adjustment unit is used to adjust the frequency of each radar sensor based on the center frequency of each radar sensor at a next moment.

[0224] In one embodiment, the second determining unit specifically includes:

[0225] a first determining subunit, configured to determine, if the current frequency adjustment mode at the current moment and the next frequency adjustment mode are consistent, a center frequency of each radar sensor at the next moment according to the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment;

[0226] The second determining subunit is configured to determine the center frequency of each radar sensor at the next moment according to the next frequency adjustment mode if the current frequency adjustment mode at the current moment and the next frequency adjustment mode are inconsistent.

[0227] In one embodiment, the first determining subunit is specifically configured to:

[0228] If the current frequency adjustment mode is the obstacle-free mode, the frequency change trend of the frequency conversion center frequency in the corresponding frequency interval of the center frequency currently assigned to each radar sensor is reversed to obtain a new center frequency currently assigned to each radar sensor. For each radar sensor, the new center frequency currently assigned to the radar sensor is used as the center frequency of the radar sensor corresponding to the next sensor number at the next moment. The sensor numbers of two adjacent radar sensors are incremented, and the sensor number next to the last sensor number is the first sensor number.

[0229] In one embodiment, the first determining subunit is specifically configured to:

[0230] If the current frequency adjustment mode is the side-front obstacle mode, the center frequency of the first target radar sensor at the next moment is determined based on the center frequency assigned to the first target radar sensor located in the side-front area of ​​the target external area at the current moment, the detection parameters corresponding to each candidate center frequency, and a frequency conversion rule. The frequency conversion rule is that the detection distance corresponding to the center frequency of the first target radar sensor at the next moment is less than the detection distance corresponding to the center frequency at the current moment. The center frequencies of radar sensors adjacent to the first target radar sensor at the next moment are determined based on the detection parameters corresponding to the center frequency of the first target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency. The center frequencies at the next moment are assigned to the remaining radar sensors with the goal of satisfying the frequency constraint condition between two adjacent radar sensors.

[0231] In one embodiment, the first determining subunit is specifically configured to:

[0232] A detection blind spot of the first target radar sensor is determined based on detection parameters corresponding to a center frequency of the first target radar sensor at a next moment, wherein the detection parameters include a detection distance and a detection range. A center frequency of a radar sensor adjacent to the first target radar sensor at a next moment is determined based on the detection blind spot and the detection parameters corresponding to each candidate center frequency. The detection parameters corresponding to the center frequency of the radar sensor adjacent to the first target radar sensor at the next moment can cover the detection blind spot.

[0233] In one embodiment, the first determining subunit is specifically configured to:

[0234] If the current frequency adjustment mode is the front obstacle mode, and the center frequency assigned to each second target radar sensor located in the area directly in front of the target external area at the current moment is the variable frequency center frequency, then the frequency change trend of the variable frequency center frequency of each second target radar sensor in the corresponding frequency interval is inversely transformed, and the inversely transformed center frequencies of each second target radar sensor are alternately transformed to obtain the center frequency of each second target radar sensor at the next moment; based on the detection parameters corresponding to the center frequency of the second target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency, the maximum center frequency or the minimum center frequency is assigned to the radar sensor adjacent to the second target radar sensor at the next moment; and with the goal of satisfying the frequency constraint condition between two adjacent radar sensors, the center frequencies of the remaining radar sensors are assigned at the next moment.

[0235] In one embodiment, the first determining unit is specifically configured to:

[0236] If the obstacle detection situation is that no obstacle is detected, the next frequency adjustment mode at the next moment is determined to be the no obstacle mode; if the obstacle detection situation is that an obstacle is detected in front of the side of the target external area, the next frequency adjustment mode at the next moment is determined to be the side-front obstacle mode; if the obstacle detection situation is that an obstacle is detected directly in front of the target external area, the next frequency adjustment mode at the next moment is determined to be the directly in front obstacle mode.

[0237] Each module in the obstacle detection device described above may be implemented in whole or in part through software, hardware, or a combination thereof. Each module may be embedded in or independent of a processor in a computer device in the form of hardware, or may be stored in a memory in the computer device in the form of software, so that the processor can call and execute the corresponding operations of each module.

[0238] In one embodiment, a computer device is provided, which includes a SOC, and its internal structure diagram can be as follows: Figure 13 As shown. The computer device includes a processor, a memory, and a network interface connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The database of the computer device is used to store data on various candidate center frequencies. The network interface of the computer device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, an obstacle detection method is implemented.

[0239] Those skilled in the art will understand that Figure 13 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0240] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps of the obstacle detection method described in any of the above embodiments when executing the computer program.

[0241] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the obstacle detection method described in any of the above embodiments are implemented.

[0242] In one embodiment, a computer program product is provided, including a computer program. When the computer program is executed by a processor, the steps of the obstacle detection method described in any of the above embodiments are implemented.

[0243] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory may include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processor involved in the various embodiments provided herein may be, but are not limited to, a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic unit, a data processing logic unit based on quantum computing, and the like.

[0244] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0245] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. An obstacle detection method, characterized in that: The method comprises: Obtaining current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency assigned at the current moment; Determining an obstacle detection status of the vehicle based on each current detection data; According to the obstacle detection situation, the frequency of each radar sensor is adjusted to continuously detect obstacles around the vehicle; The radar sensors are of the same type, and frequency constraints are satisfied between two adjacent radar sensors. The frequency constraints include whether frequency intervals corresponding to center frequencies of the two adjacent radar sensors overlap or do not overlap. If overlap exists, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval. The two variable frequency center frequencies have opposite frequency change trends and different frequency change rates within the corresponding frequency interval, and the frequency change trend of the variable frequency center frequencies within the corresponding frequency interval is increasing or decreasing.

2. The method according to claim 1, characterized in that The center frequency currently assigned to each radar sensor is selected from candidate center frequencies; wherein the number of candidate center frequencies is the same as the number of radar sensors deployed within the target external area, and the candidate center frequencies include a fixed-frequency center frequency and a variable-frequency center frequency.

3. The method according to claim 2, characterized in that Each candidate center frequency is determined by: The operating frequency range of the radar sensor is divided to obtain at least two fixed-frequency center frequencies; wherein the frequency intervals corresponding to two adjacent fixed-frequency center frequencies do not overlap; When the number of deployed radar sensors is greater than the number of frequencies of the fixed-frequency center frequency, determining a difference between the number of deployed radar sensors and the number of frequencies; Adding the variable frequency center frequencies of the said difference value between adjacent fixed frequency center frequencies; wherein the frequency intervals corresponding to two adjacent variable frequency center frequencies do not overlap.

4. The method according to claim 1, wherein The frequency adjustment of each radar sensor according to the obstacle detection situation includes: determining a next frequency adjustment mode at a next moment according to the obstacle detection situation; determining the center frequency of each radar sensor at a next moment according to consistency between the current frequency adjustment mode at the current moment and the next frequency adjustment mode; Based on the center frequency of each radar sensor at the next moment, the frequency of each radar sensor is adjusted.

5. The method according to claim 4, characterized in that The determining, based on consistency between the current frequency adjustment mode at the current moment and the next frequency adjustment mode, the center frequency of each radar sensor at the next moment includes: If the current frequency adjustment mode at the current moment is consistent with the next frequency adjustment mode, determining the center frequency of each radar sensor at the next moment according to the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment; If the current frequency adjustment mode at the current moment is inconsistent with the next frequency adjustment mode, the center frequency of each radar sensor at the next moment is determined according to the next frequency adjustment mode.

6. The method according to claim 5, characterized in that The determining, according to the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment, the center frequency of each radar sensor at the next moment includes: If the current frequency adjustment mode is the obstacle-free mode, performing an inverse transformation on a frequency change trend of a frequency conversion center frequency in a corresponding frequency interval of the center frequency currently allocated to each radar sensor to obtain a new center frequency currently allocated to each radar sensor; For each radar sensor, the center frequency newly allocated to the radar sensor at the current moment is used as the center frequency of the radar sensor corresponding to the next sensor number at the next moment; The sensor numbers of two adjacent radar sensors are incremented, and the next sensor number after the last sensor number is the first sensor number.

7. The method according to claim 5, characterized in that The determining, according to the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment, the center frequency of each radar sensor at the next moment includes: If the current frequency adjustment mode is the side-front obstacle mode, determining the center frequency of the first target radar sensor at a next moment based on the center frequency currently assigned to the first target radar sensor located in the side-front area of ​​the target external area, detection parameters corresponding to each candidate center frequency, and a frequency conversion rule; wherein the frequency conversion rule is such that the detection range corresponding to the center frequency of the first target radar sensor at the next moment is less than the detection range corresponding to the center frequency at the current moment; determining, based on the detection parameter corresponding to the center frequency of the first target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency, a center frequency of a radar sensor adjacent to the first target radar sensor at the next moment; With the goal of satisfying the frequency constraint condition between two adjacent radar sensors, the center frequencies at the next moment are allocated to the remaining radar sensors.

8. The method according to claim 7, characterized in that The determining, based on the detection parameter corresponding to the center frequency of the first target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency, the center frequency of the radar sensor adjacent to the first target radar sensor at the next moment includes: determining a detection blind spot of the first target radar sensor based on detection parameters corresponding to the center frequency of the first target radar sensor at a next moment; wherein the detection parameters include a detection distance and a detection range; Determine, based on the detection blind spot and detection parameters corresponding to each candidate center frequency, a center frequency of a radar sensor adjacent to the first target radar sensor at a next moment; wherein the detection parameters corresponding to the center frequency of the radar sensor adjacent to the first target radar sensor at the next moment can cover the detection blind spot.

9. The method according to claim 5, characterized in that The determining, according to the current frequency adjustment mode and the center frequency allocated to each radar sensor at the current moment, the center frequency of each radar sensor at the next moment includes: If the current frequency adjustment mode is the front obstacle mode, and the center frequency assigned to each second target radar sensor located in the area directly in front of the target external area at the current moment is the frequency conversion center frequency, then performing an inverse transformation on the frequency change trend of the frequency conversion center frequency of each second target radar sensor in the corresponding frequency interval, and alternately transforming the inversely transformed center frequencies of each second target radar sensor to obtain the center frequency of each second target radar sensor at the next moment; allocating a maximum center frequency or a minimum center frequency at the next moment to a radar sensor adjacent to the second target radar sensor based on the detection parameter corresponding to the center frequency of the second target radar sensor at the next moment and the detection parameters corresponding to each candidate center frequency; With the goal of satisfying the frequency constraint condition between two adjacent radar sensors, the center frequencies at the next moment are allocated to the remaining radar sensors.

10. The method according to claim 4, characterized in that Determining a next frequency adjustment mode at a next moment according to the obstacle detection situation includes: If the obstacle detection condition is that no obstacle is detected, determining that the next frequency adjustment mode at the next moment is the obstacle-free mode; If the obstacle detection condition is that an obstacle is detected in front of the side of the target external area, determining the next frequency adjustment mode at the next moment to be the side-front obstacle mode; If the obstacle detection condition is that an obstacle is detected right in front of the target external area, the next frequency adjustment mode at the next moment is determined to be the front obstacle mode.

11. An obstacle detection device, characterized in that: The device comprises: An acquisition module is used to obtain current detection data collected by each radar sensor in the target external area on the vehicle based on the center frequency allocated at the current moment; A determination module, configured to determine an obstacle detection status of the vehicle based on each current detection data; an adjustment module, configured to adjust the frequency of each radar sensor according to the obstacle detection situation, so as to continuously detect obstacles around the vehicle; The radar sensors are of the same type, and frequency constraints are satisfied between two adjacent radar sensors. The frequency constraints include whether frequency intervals corresponding to center frequencies of the two adjacent radar sensors overlap or do not overlap. If overlap exists, the center frequencies of the two adjacent radar sensors are a variable frequency center frequency and a fixed frequency center frequency, or two variable frequency center frequencies with the same frequency interval. The two variable frequency center frequencies have opposite frequency change trends and different frequency change rates within the corresponding frequency interval, and the frequency change trend of the variable frequency center frequencies within the corresponding frequency interval is increasing or decreasing.

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