An imaging radar echo adaptive gain control method, device and storage medium

Abstract

The application discloses an imaging radar echo adaptive gain control method and device and a storage medium. An AD acquisition module acquires echo signals of each sampling point obtained by an echo receiving channel in a set time period; the echo data amplitude is calculated to construct a histogram; the histogram is converted into a binary histogram; a binary histogram of an echo template is obtained; a gain state corresponding to an echo template corresponding to a maximum correlation coefficient is selected as a gain state of the acquired echo data; and the gain of the echo receiving channel is adjusted. The application calculates the histogram from the echo data, sets a threshold M according to the number of sampling points, obtains a binary histogram of the echo data, does not need to consider other information of the data, judges the size of the echo data according to the correlation coefficient of the binary histogram of the echo template, and can determine the gain state of the echo receiving channel according to the state of the echo by the digital end when there is no AGC circuit.

Description

Technical Field

[0001] This invention belongs to the field of radar signal processing technology, specifically relating to an adaptive gain control method, device, and storage medium for imaging radar echoes. Background Technology

[0002] Radar imaging technology is increasingly developing towards higher resolution, higher integration, and higher reliability, placing higher demands on radar sampling channels and data transmission speeds. AD sampling equipment quantizes radar echo samples and then performs a series of digital signal processing steps, including digital demodulation, decimation filtering, beamforming, FFT, and pulse compression. Meanwhile, a single SAR image can generate hundreds of gigabytes (GB) to terabytes (TB) of echo data. To avoid system failures, abnormal parameter configurations, and other errors that could lead to abnormal echo states and waste of resources, echo data status detection is crucial.

[0003] Currently, radar echo data transmission links are all based on high-speed interfaces, resulting in large amounts of echo data. During the initial debugging phase, echo data status monitoring relies on connecting to a debugging simulator to capture the status. While this monitoring method can quickly locate problems during the initial debugging phase, it wastes manpower during the mid-term debugging phase, and becomes unsuitable after product delivery.

[0004] Another common method is to statistically analyze the size of echo data. Data below a threshold is considered noise, data above the threshold is considered overflow, and data between the thresholds is considered valid. For example, a radar echo data processing method disclosed in patent application number 202010512096.5 replaces the corresponding initial judgment parameters based on at least one of a determined top-height echo threshold, vertical gradient value, and echo change threshold, and then filters the radar base data based on the replaced initial judgment parameters. Because this method statistically analyzes the size of echo data, it consumes a lot of resources and has a large echo processing delay.

[0005] Furthermore, the link gain plays a crucial role in echo monitoring. When the link gain is too low, the system sensitivity decreases, failing to reach the target monitoring threshold; conversely, when the link gain is too high, it can cause signal saturation by including the target echo along with other background targets, making it difficult to distinguish the target echo. Therefore, by determining the state of the acquired echoes, the link gain can be assessed, and adjusting the link gain can prevent signal overload and saturation when monitoring the target echo. Summary of the Invention

[0006] The purpose of this invention is to address the aforementioned problems in the prior art by providing an adaptive gain control method, device, and storage medium for imaging radar echo. The method involves acquiring the signal amplitude of the echo data after AD acquisition, calculating a binarized histogram, and performing autocorrelation calculations with echo templates representing different gain states. The echo templates are distributed according to gain from weak to strong. The autocorrelation calculation determines the state of the echo data, indicating the gain status of the echo receiving channel link. Adjusting the gain state yields the optimal echo data.

[0007] The present invention solves the above-mentioned technical problems through the following technical means:

[0008] An adaptive gain control method for imaging radar echo includes the following steps:

[0009] Step 1: The AD acquisition module acquires the echo signals from each sampling point obtained by the echo receiving channel within a set time period;

[0010] Step 2: Calculate the real and imaginary parts of the echo data based on the echo data from each sampling point, further calculate the echo data amplitude, and construct a histogram. The horizontal axis of the histogram represents the bit depth, and the vertical axis represents the number of echo data points whose amplitudes are merged to the bit depth.

[0011] Step 3: Convert the histogram to a binary histogram;

[0012] Step 4: Obtain the binarized histograms of various echo templates representing different gain states;

[0013] Step 5: Calculate the correlation coefficient between the binarized histogram and the binarized histogram of each echo template obtained in Step 3, and select the gain state corresponding to the echo template with the largest correlation coefficient as the gain state of the acquired echo data corresponding to the binarized histogram obtained in Step 3.

[0014] Step 6: Adjust the gain of the echo receiving channel according to the gain status of the collected echo data.

[0015] As mentioned above in step 2, each bit corresponds to an echo data amplitude. If the amplitude of the acquired echo data is between the echo data amplitudes represented by two bit points, then the acquired echo data amplitude is merged into the nearest bit point.

[0016] As mentioned above in step 2, the difference in echo data amplitude represented by adjacent bit points on the horizontal axis of the histogram is B / (2). N-1 N is the number of sampling bits of the AD sampling module, and B is the input range amplitude of the AD acquisition module.

[0017] As described above, converting a histogram into a binary histogram includes: setting the threshold M to 10-20% of the number of sampling points within a set time period; setting the ordinate value of the histogram where the number of echo data is greater than or equal to the set threshold M to 1; and setting the ordinate value of the histogram where the number of echo data is less than the set threshold M to 0.

[0018] As mentioned above, the correlation coefficient is based on the following formula:

[0019]

[0020] R is the correlation coefficient, A is the number of bit points whose ordinate values ​​of the corresponding bit points in the binary histogram and echo template obtained in step 3 equal 0 after modulo 2 operation, and D is the number of bit points whose ordinate values ​​of the corresponding bit points in the binary histogram and echo template obtained in step 3 equal 1 after modulo 2 operation.

[0021] As mentioned above, the gain states include weak echo, optimal echo, and strong echo.

[0022] Step 6, adjusting the gain of the echo receiving channel, includes the following steps:

[0023] If the gain status of the acquired echo data is weak echo, then increase the gain of the echo receiving channel by the set gain step size and return to step 1.

[0024] If the gain state of the collected echo data is optimal, then the gain of the echo receiving channel does not need to be changed, and return to step 1.

[0025] If the gain state of the acquired echo data is strong echo, then reduce the gain of the echo receiving channel by the set gain step size and return to step 1.

[0026] A computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the above-described gain control method.

[0027] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described gain control method.

[0028] A computer program product includes a computer program that, when executed by a processor, implements the steps of the above-described gain control method.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] The echo data is calculated to obtain a histogram. Then, a threshold M is set by the number of sampling points to obtain a binary histogram of the echo data. There is no need to consider other information of the data. The magnitude of the echo data is determined by the correlation coefficient with the binary histogram of the echo template. In the absence of an AGC circuit, the gain state of the echo receiving channel can be determined by the digital end based on the state of the echo.

[0031] The correlation coefficient is calculated between the binarized histogram of the echo data transformation and the binarized histogram of the echo template representing different gain states pre-written in the FPGA. Since the sampled echo data has been processed into a binarized histogram, which is equivalent to a 0 / 1 sequence, the FPGA does not need to perform too complicated processing to obtain the relationship between the echo data and the pre-written echo template representing various gain states, and adjust the gain state of the echo receiving channel. Attached Figure Description

[0032] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0033] To facilitate understanding and use of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to embodiments. It should be understood that the embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0034] Example 1:

[0035] like Figure 1 The aforementioned imaging radar echo adaptive gain control method includes the following steps:

[0036] Step 1: Acquire echo data. The digital terminal acquires the echo signal obtained by the echo receiving channel through the AD acquisition module, and obtains the echo data of each sampling point within a set time period by reading the data register of the AD acquisition module.

[0037] Step 2: Calculate the real part I and imaginary part Q of the echo data based on the echo data from each sampling point. Further calculate the echo data amplitude (I). 2 +Q 2 ) 1 / 2 Construct a histogram where the horizontal axis represents the bit depth and the vertical axis represents the number of echo data points whose amplitudes are merged to the bit depth.

[0038] The echo data amplitude within a set time period is converted into a histogram for statistical analysis. In this embodiment, the AD acquisition module is a bipolar sampling module that can acquire input positive and negative analog signals. B is the input range amplitude of the AD acquisition module. The maximum absolute value of the positive and negative analog signals that the AD acquisition module can acquire is the same, both being B. The highest bit in the data register of the bipolar AD acquisition module represents the sign bit. Each horizontal axis of the histogram represents a bit point, and each bit point corresponds to an echo data amplitude. The acquired echo data amplitudes are merged into the echo data amplitudes corresponding to each bit point. If the acquired echo data amplitude is between the echo data amplitudes represented by two bit points, the acquired echo data amplitude is merged into the nearest bit point (i.e., the bit point with the smallest difference in echo data amplitudes). The difference in echo data amplitudes represented by adjacent bit points on the horizontal axis is B / (2π / 3). N-1 N is the number of sampling bits in the AD sampling module. For a bipolar AD sampling module, the highest bit is the sign bit, so the resolution is B / (2πf). N-1 The vertical axis of the histogram represents the number of echo data points corresponding to the bit points.

[0039] Step 3: Convert the histogram obtained in Step 2 into a binary histogram with only 0 and 1 on the ordinate. First, set a threshold M based on the sampling points. The threshold M is set to 10-20% of the number of sampling points X within a set time period. Set the ordinate value of the histogram where the number of echo data points is greater than or equal to the threshold M to 1, and set the ordinate value of the histogram where the number of echo data points is less than the threshold M to 0, thus generating a binary histogram. Converting the histogram to a binary histogram facilitates subsequent correlation coefficient calculations, reducing the computational workload. The threshold M can also be adjusted according to the actual situation.

[0040] Step 4: Obtain binarized histograms of various echo templates representing different gain states. As a preferred option, the binarized histograms of various echo templates representing different gain states are pre-written into the FPGA. The difference in echo data amplitude represented by adjacent bit points on the horizontal axis of the binarized histogram of the echo template and the binarized histogram in Step 3 is the same. In this embodiment, the gain states include weak echo, best echo, and strong echo.

[0041] Step 5: Calculate the correlation coefficient between the binarized histogram obtained in Step 3 and the binarized histograms of each echo template. Select the gain state corresponding to the echo template with the largest correlation coefficient as the gain state of the acquired echo data corresponding to the binarized histogram obtained in Step 3.

[0042] The correlation coefficient R is based on the following formula:

[0043]

[0044] A represents the number of bit points whose ordinate values ​​equal 0 after modulo 2 operation of the corresponding bit points in the binary histogram and echo template obtained in step 3, and D represents the number of bit points whose ordinate values ​​equal 1 after modulo 2 operation of the corresponding bit points in the binary histogram and echo template obtained in step 3. This represents modulo-2 operation, and the rules of modulo-2 operation are as follows:

[0045] Step 6: Adjust the gain of the echo receiving channel according to the gain status of the collected echo data.

[0046] If the gain status of the acquired echo data is weak echo, then increase the gain of the echo receiving channel by the set gain step size and return to step 1.

[0047] If the gain state of the collected echo data is optimal, then the gain of the echo receiving channel does not need to be changed, and return to step 1.

[0048] If the gain state of the acquired echo data is strong echo, then reduce the gain of the echo receiving channel by the set gain step size and return to step 1.

[0049] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. 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 methods.

[0050] Example 2:

[0051] This embodiment provides a computer device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the various steps in Embodiment 1 above.

[0052] Example 3:

[0053] This embodiment provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in Embodiment 1 above.

[0054] Example 4:

[0055] A computer program product includes a computer program that, when executed by a processor, implements the steps in Embodiment 1 described above.

[0056] It should be noted that the embodiments described in this invention are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains can make various modifications or additions to the described embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. An imaging radar return adaptive gain control method, characterized by, Includes the following steps: Step 1: The AD acquisition module acquires the echo signals from each sampling point obtained by the echo receiving channel within a set time period; Step 2: Calculate the real and imaginary parts of the echo data based on the echo data from each sampling point, further calculate the echo data amplitude, and construct a histogram. The horizontal axis of the histogram represents the bit depth, and the vertical axis represents the number of echo data points whose amplitudes are merged to the bit depth. Step 3: Convert the histogram to a binary histogram; Step 4: Obtain the binarized histograms of various echo templates representing different gain states; Step 5: Calculate the correlation coefficient between the binarized histogram and the binarized histogram of each echo template obtained in Step 3, and select the gain state corresponding to the echo template with the largest correlation coefficient as the gain state of the acquired echo data corresponding to the binarized histogram obtained in Step 3. Step 6: Adjust the gain of the echo receiving channel according to the gain status of the collected echo data.

2. The imaging radar echo adaptive gain control method according to claim 1, characterized in that, In step 2, each bit point corresponds to an echo data amplitude. If the amplitude of the acquired echo data is between the echo data amplitudes represented by two bit points, then the acquired echo data amplitude is merged into the nearest bit point.

3. The method of claim 1, wherein, In step 2, the difference in echo data amplitude represented by adjacent bit points on the horizontal axis of the histogram is B / (2). N -1), N is the number of sampling bits of the AD sampling module, and B is the input range amplitude of the AD acquisition module.

4. The method of claim 1, wherein, The process of converting a histogram into a binary histogram includes: setting a threshold M to 10-20% of the number of sampling points within a set time period; setting the ordinate value of the histogram where the number of echo data is greater than or equal to the set threshold M to 1; and setting the ordinate value of the histogram where the number of echo data is less than the set threshold M to 0.

5. The method of claim 1, wherein, The correlation coefficient is based on the following formula: R is the correlation coefficient, A is the number of bit points whose ordinate values ​​of the corresponding bit points in the binary histogram and echo template obtained in step 3 equal 0 after modulo 2 operation, and D is the number of bit points whose ordinate values ​​of the corresponding bit points in the binary histogram and echo template obtained in step 3 equal 1 after modulo 2 operation.

6. The method of claim 1, wherein, The gain states include weak echo, optimal echo, and strong echo. Step 6, adjusting the gain of the echo receiving channel, includes the following steps: If the gain status of the acquired echo data is weak echo, then increase the gain of the echo receiving channel by the set gain step size and return to step 1. If the gain state of the collected echo data is optimal, then the gain of the echo receiving channel does not need to be changed, and return to step 1. If the gain state of the acquired echo data is strong echo, then reduce the gain of the echo receiving channel by the set gain step size and return to step 1. 7.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-6 when the computer program is executed by the processor. When the processor executes the computer program, it implements the steps of the gain control method according to any one of claims 1 to 6.

8. A computer readable storage medium having stored thereon a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the gain control method according to any one of claims 1 to 6.

9. A computer program product comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the gain control method according to any one of claims 1 to 6.

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