A millimeter-wave radar target detection method

Abstract

This invention relates to the field of radar target detection, specifically a millimeter-wave radar target detection method that solves the problems of low detection accuracy in miniaturized and low-power millimeter-wave radars in existing technologies. The invention includes the following steps: S1: Calibration of the test environment; S2: The radar operates in a first working mode with a low frame rate to confirm whether it is the same target and determine whether to switch modes; S3: The radar switches to a second working mode with a high frame rate. If the target can be detected within time T3, proceed to step S4; S4: Actions taken by the radar after detecting the target in the second working mode. This invention significantly reduces the average power consumption of radar detection by using multi-mode switching; by partitioning the test environment and identifying interference in the environment, it improves anti-interference performance, detection accuracy, and stability under low power conditions.

Description

Technical Field

[0001] This invention relates to the field of radar target detection, and in particular to a millimeter-wave radar target detection method. Background Technology

[0002] In recent years, with the development of the consumer millimeter-wave market in smart homes, security, and industrial fields, and driven by considerations such as cost reduction, ease of installation, and widespread application, more and more markets are demanding that millimeter-wave radar possess miniaturization, high performance, and long battery life. Therefore, miniaturized low-power radar has become a development trend in millimeter-wave radar in recent years. However, miniaturization and low-power design have also led to a decrease in radar detection accuracy and increased susceptibility to interference.

[0003] There is an urgent need for a new target detection method using millimeter-wave radar that can solve the above problems. Summary of the Invention

[0004] The present invention proposes a millimeter-wave radar target detection method, which solves the problems of low detection accuracy of miniaturized and low-power millimeter-wave radar in the prior art.

[0005] The technical solution of this invention is implemented as follows: A millimeter-wave radar target detection method includes the following steps: S1: Test environment calibration: The radar is in calibration mode to acquire signals from the test environment and send them to the main control unit for analysis, acquiring and storing distance, velocity, angle information and signal-to-noise ratio; the calibration holding time is T1; S2: Radar operates in a first working mode with a low frame rate: Target detection is performed in each frame, range-velocity spectrum analysis is performed on the signal, and the presence of a target is determined according to a set threshold. If the signal exceeds the threshold, the distance, velocity, and angle information of the target are acquired and target association is performed; when the distance, velocity, and angle information of the targets detected in two frames meet the threshold, it is confirmed that they are the same target; in the Nth frame to... If the same target is detected with a probability of more than P% within the N+W frames, the radar proceeds to step S3; otherwise, it remains in S2. S3: The radar switches to a second working mode with a high frame rate. The second working mode is maintained for T3 hours. For each frame, the radar detects the target's distance, speed, and angle information. If the radar does not detect the target within T3 hours, it exits the second working mode and returns to S2. If the target is detected within T3 hours, it proceeds to step S4. S4: The radar's actions after detecting the target in the second working mode can be set autonomously. After step S4, the millimeter-wave radar can be set to enter a sleep state with a sleep time window T4. After T4, it returns to step S2 to restart detection.

[0006] The calibration mode can divide the area to be tested into zones and store the distance, speed, and angle information of different zones separately for comparison with subsequent tests.

[0007] Interference information elimination: Targets continuously detected in S1 are stored as interference signals. When the radar operates in the second working mode of S3, the stored interference signals are eliminated first.

[0008] Step S2 also includes frame period setting: the frame period is set to M levels, with the frame period gradually increasing at each level; when the radar starts or returns from S3 or S4 to S2: the frame period starts from the first level, and if the mode switching conditions are not met within the set time period, the frame period is gradually increased according to the time window T2 to reduce the frame rate.

[0009] The actions after the target is detected in step S4 may include: (1) tracking the target. After the target is detected, continue to detect it in the next time window T3 until no target is detected in time window T3, and then return to S2; (2) feeding back to the main control unit: send a signal that the target has been detected to the main control unit, return to the detection state or issue an instruction to the controlled device, and the main control or the controlled device shall carry out subsequent actions.

[0010] This invention discloses a millimeter-wave radar target detection method that significantly reduces the average power consumption of radar detection by using multi-mode switching; by partitioning the test environment and identifying interference in the environment, it improves anti-interference performance, detection accuracy and stability under low power consumption conditions. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 Radar normal operation flowchart;

[0013] Figure 2 Calibration mode flowchart. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] This invention discloses a millimeter-wave radar target detection method, comprising the following steps:

[0016] S1: Test Environment Calibration: The radar is in calibration mode, used to acquire signals from the test environment and send them to the main control unit for analysis, acquiring and storing distance, speed, angle information and signal-to-noise ratio; the calibration hold time is T1; if T1 is set to 1 minute, it means that each calibration will last for 1 minute; at this time, the current environment must be the environment that the user needs the radar to detect, and it must be ensured that there are no pedestrians or vehicles waiting to be detected in the current environment;

[0017] S2: The radar operates in the first working mode, a low frame rate state for coarse detection: precise identification is not required, so the millimeter-wave radar is set to operate in a low frame rate state to reduce overall power consumption. During the detection process, it needs to be compared with the stored calibration information to eliminate interference from complex environments and improve the reliability of detection. Target detection is performed within each frame, and range-velocity spectrum analysis is performed on the signal. The presence of a target is determined according to the set threshold. If the signal exceeds the threshold, the target's range, velocity, and angle information are obtained and target association is performed. If the range, velocity, and angle information of the targets detected in two frames meet the threshold, they are confirmed to be the same target. The target's range and velocity information can be obtained based on its position in the range-velocity spectrum. The target's angle information can be obtained by performing DOA (Direction of Arrival) localization estimation on the signal. Target association is performed between different frames. If the range, velocity, and angle information of the targets detected in two frames meet the threshold, they are considered to be the same target. If the same target is detected with a probability greater than P in frames N to N+W, the radar proceeds to step S3; otherwise, it remains in S2. The detection time window W and the detection probability P can be set by the user according to actual needs.

[0018] S3: The radar switches to the second working mode for high-frame-rate precision detection: the second working mode is maintained for T3 hours; the second working mode performs precise detection and identification of targets from the first working mode; similarly, for each frame of signal detected by the radar, environmental interference during calibration must first be eliminated, and then the target's distance, speed, and angle information must be detected. If the radar does not detect the target within T3 hours, it exits the second working mode and returns to S2; if the target can be detected within T3 hours, it proceeds to step S4.

[0019] S4: The radar's action after detecting a target in the second operating mode can be set autonomously. After step S4, the millimeter-wave radar can be set to enter a sleep state with a sleep time window T4. After T4, it returns to step S2 to restart detection. The user can set this sleep time window according to actual needs to avoid frequent entry into the second operating mode caused by the target moving within the detection area, as well as poor user experience caused by frequent signal transmission to the main and controlled devices, while also reducing power consumption.

[0020] The calibration mode can partition the test area and store the distance, velocity, and angle information of different areas separately for comparison with subsequent detections. By storing the signal characteristics of different areas for comparison with subsequent detections, the detection accuracy is improved. For example, if a target can be continuously detected in area A of the calibration mode, the target may be due to interference in the environment. In this case, the influence of this interference can be eliminated when processing area A.

[0021] Interference information elimination: Targets continuously detected in S1 are stored as interference signals. When the radar operates in the second working mode of S3, the stored interference signals are eliminated first.

[0022] When the environment to be tested remains unchanged, the calibration mode only needs to be run once during initial power-on. If the environment changes, recalibration is required. For example, if the radar is installed on the eaves and needs to detect whether a person or vehicle has entered the yard, only one calibration is needed if the yard environment remains unchanged. However, if new landscaping trees are planted in the yard, recalibration is required. This avoids the impact of environmental changes on detection accuracy.

[0023] Step S2 further includes setting the frame period: setting the frame period to M levels, with the frame period gradually increasing at each level; when the radar starts or returns from S3 or S4 to S2: the frame period starts from the first level, and if the mode switching condition is not met within the set time period, the frame period is increased step by step according to the time window T2, and the frame rate is reduced; for example, if the mode switching condition is not met within T2 time, the frame period rises to the second level, and if the mode switching condition is not met within the subsequent T2 time, the frame period rises to the third level, and so on, and the frame period remains at the Mth level and does not increase further.

[0024] The actions after the target is detected in step S4 may include: (1) tracking the target. After the target is detected, continue to detect it in the next time window T3 until no target is detected in time window T3, and then return to S2; (2) feeding back to the main control unit: send a signal that the target has been detected to the main control unit, return to the detection state or issue an instruction to the controlled device, so that the main control or the controlled device can carry out subsequent actions, such as sending a detected signal to the mobile phone or controlling the camera to start recording.

[0025] Combination Figure 1 Radar normal operation flowchart and Figure 2As shown in the calibration mode flowchart, when the radar equipment starts working, it first enters the calibration mode to calibrate the test environment. The test environment is divided into zones, and the range, velocity, angle information, and signal-to-noise ratio of each zone are extracted and stored. Continuously detected targets in the environment are excluded, and this information is stored in the main control unit. The equipment then enters the first working mode, identifying the environment at a low frame rate. Each frame is compared with the stored calibration information to eliminate interference from complex environments and improve detection reliability. Range-velocity spectrum analysis is performed on the signal, and the presence of a target is determined based on a set threshold. If the signal exceeds the threshold, a target is considered to exist. The target's range and velocity information can be obtained based on its position in the range-velocity spectrum. DOA (Direction of Arrival) estimation is performed on the signal to obtain the target's angle information. Target association is performed between different frames; if the range, velocity, and angle information of targets detected in two frames meet the thresholds, they are considered to be the same target.

[0026] If the same target is detected with a probability exceeding P within frames N to N+W, the radar switches to the second operating mode for more precise high-frame-rate detection. Each frame is compared with stored calibration information to eliminate interference from complex environments before detecting the target's distance, velocity, and angle. If the radar detects the target within time T3, it proceeds to step S4, where the user specifies subsequent actions.

[0027] After the subsequent actions are completed, the system can enter a dormant period or the first working mode according to user settings.

[0028] By switching modes, the radar can reduce power consumption while maintaining detection accuracy.

[0029] In the first operating mode, if no target is detected, the power consumption is further reduced by gradually decreasing the frame period, thereby reducing the average power consumption of the radar.

[0030] To address the issue of decreased detection accuracy in low-power radar: a two-level operating mode is set up. When a target is roughly detected, the second-level operating mode is entered for precise detection, which can improve detection accuracy and stability while maintaining low power consumption.

[0031] To address the issue of low-power radar being susceptible to interference: Before using the radar, a calibration mode is used to calibrate the test environment. This eliminates interference that may exist in complex environments, such as metal, building, and plant movement, thus avoiding the impact of interference detection and improving detection accuracy.

[0032] A lower power consumption detection solution is provided: the calibration mode performs feature extraction and region division of the test environment to avoid false detections caused by interference during the detection process, effectively reducing power consumption; a two-level working mode is used. In the absence of a target, the radar operates in the first working mode. The first working mode sets multiple frame periods, which can reduce power consumption in scenarios where there is no target for a long time; furthermore, it can effectively reduce the average power consumption of the entire device.

[0033] This invention discloses a millimeter-wave radar target detection method that significantly reduces the average power consumption of radar detection by using multi-mode switching; by partitioning the test environment and identifying interference in the environment, it improves anti-interference performance, detection accuracy and stability under low power consumption conditions.

[0034] Of course, those skilled in the art should be able to make various corresponding changes and modifications based on the present invention without departing from its spirit and essence, but all such changes and modifications should fall within the protection scope of the appended claims.

Claims

1. A millimeter-wave radar target detection method, characterized in that: Includes the following steps: S1: Test Environment Calibration: The radar is in calibration mode to acquire signals from the test environment and send them to the main control unit for analysis, acquiring and storing distance, speed, angle information and signal-to-noise ratio; the calibration hold time is T1; the calibration mode divides the test area into zones and stores the distance, speed and angle information of different zones separately for comparison with subsequent detection. S2: The radar operates in the first working mode at a low frame rate: target detection is performed in each frame, range-velocity spectrum analysis is performed on the signal, and the presence of a target is determined according to the set threshold. If the signal exceeds the threshold, the target's range, velocity, and angle information are acquired and the target is associated. If the distance, velocity, and angle information of the target detected in two frames meet the threshold, it is confirmed that they are the same target; If the same target is detected with a probability of more than P in frames N to N+W, the radar proceeds to step S3; otherwise, it remains in step S2. S3: The radar operating mode switches to the second operating mode of high frame rate: the second operating mode is held for T3. The radar detects signals in each frame, including the target's distance, speed, and angle information. If the radar does not detect the target within time T3, it exits the second working mode and returns to S2. If the target can be detected within time T3, proceed to step S4; S4: The radar autonomously sets its actions after detecting a target in the second operating mode; After step S4 is completed, the millimeter-wave radar is set to enter a sleep state, and a sleep time window T4 is set. After T4, the process returns to step S2 to start detection again.

2. The millimeter-wave radar target detection method according to claim 1, characterized in that: Interference information elimination: Targets continuously detected in S1 are stored as interference signals. When the radar operates in the second working mode of S3, the stored interference signals are eliminated first.

3. The millimeter-wave radar target detection method according to claim 2, characterized in that: Step S2 also includes frame period setting: the frame period is set to M levels, and the frame period of each level gradually increases; When the radar is started or returns from S3 or S4 to S2: the frame period starts from the first level. If the mode switching conditions are not met within the set time period, the frame period is increased step by step according to the time window T2, and the frame rate is reduced.

4. The millimeter-wave radar target detection method according to claim 3, characterized in that: The actions taken after detecting the target in step S4 include: (1) Track the target. After the target is detected, continue to detect it in the next time window T3 until no target is detected in time window T3, then return to S2; (2) Feedback to the main control unit: Send a signal that the target has been detected to the main control unit, return the detection status or issue an instruction to the controlled device, and the main control or the controlled device shall carry out subsequent actions.

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