Method for analyzing laser radar signal through intermediate frequency data

Abstract

The invention discloses a method for analyzing a laser radar signal through intermediate frequency data in the technical field of laser radar signals, and the method comprises the following steps: capturing an electric signal through a detector, and converting the electric signal into the intermediate frequency data through a frequency mixer; performing data cleaning on the intermediate frequency data; performing automatic statistical calculation on the cleaned data to obtain new signal parameters; the signal parameter reliability is manually and repeatedly confirmed; trusted signal parameters are stored in a signal parameter library, a regulation and control mechanism improves the detection performance and the anti-interference capability of a radar system, a feedback mechanism acts on a data selector, interference signals are reduced, and meanwhile the signal parameter library is automatically updated. According to the method for analyzing the laser radar signal through the intermediate frequency data, the data processing complexity is reduced, and the data accuracy and stability are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser radar signals, and in particular to a method for analyzing laser radar signals through intermediate frequency data. Background Art

[0002] As a high-precision environmental perception sensor, LiDAR is widely used in various fields. However, for subsequent data processing, strong computing power is required for real-time processing, which greatly increases the complexity and cost of the system. Intermediate frequency data processing and analysis of LiDAR signals is a key link in the radar system, mainly involving the acquisition, processing and analysis of intermediate frequency signals; intermediate frequency data processing plays a core role in radar signal processing. It involves converting the received RF signal into an intermediate frequency signal, and then performing a series of processing on the intermediate frequency signal to extract useful information. Intermediate frequency signal is the name of the radio frequency in the range of 300kHz to 3MHz in the LiDAR system. Part of this frequency band is the medium wave amplitude modulation broadcast band, and the intermediate frequency band is also called the hundred-meter band1. In the radar system, the antenna receives electromagnetic waves in space and converts them into electrical signals, namely RF signals. The RF module down-converts this high-frequency signal to a frequency that the intermediate frequency module can receive, such as 100MHz, to obtain an intermediate frequency signal. In LiDAR signal processing, intermediate frequency data processing is a key step. First, the electromagnetic waves received by the antenna are converted into RF signals, and then down-converted to a frequency that can be received by an IF module, such as 100MHz, through the RF module. Next, the IF signal undergoes a digital down-conversion (DDC) process to down-convert the signal to 0 frequency, i.e., the baseband signal. In this process, the signal is amplified, filtered, and demodulated for further processing and analysis. Traditional LiDAR signal processing methods have certain limitations, greatly increasing the complexity and cost of the system, and making subsequent LiDAR signal data processing difficult, with poor accuracy and stability. Summary of the invention

[0003] The purpose of the present invention is to provide a method for analyzing lidar signals through intermediate frequency data, so as to solve the technical problems of traditional lidar signal processing methods, such as high system complexity and cost, poor accuracy and stability. The invention combines intermediate frequency data processing technology to improve the performance of lidar. The intermediate frequency technology reduces the complexity of data processing and improves data accuracy and stability through preprocessing and feature extraction. The lidar system combined with intermediate frequency data processing shows stronger adaptability when dealing with extreme weather and complex geographical environments, and has broad development prospects.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows:

[0005] The present invention provides a method for analyzing laser radar signals through intermediate frequency data, comprising the following steps:

[0006] S1. Capture the electrical signal through the detector and convert it into intermediate frequency data through the mixer;

[0007] S2. Clean the intermediate frequency data; perform automatic statistical calculations on the cleaned data to obtain new signal parameters; and manually repeat and confirm the reliability of the signal parameters;

[0008] S3. The reliable signal parameters are stored in the signal parameter library. The control mechanism improves the detection performance and anti-interference ability of the radar system. The feedback mechanism acts on the data selector to reduce the interference signal while automatically updating the signal parameter library.

[0009] As one aspect of a method for analyzing a laser radar signal through intermediate frequency data of the present invention, S1 comprises the following steps:

[0010] S11. The laser radar transmitting device emits a detection laser beam, and the detector receives the echo signal and converts the optical signal into an electrical signal;

[0011] S12. When the electrical signal is transmitted to the data selector, it is converted into intermediate frequency data through a mixer according to different detection channel input signals.

[0012] As one aspect of a method for analyzing a laser radar signal through intermediate frequency data of the present invention, the S12 comprises the following steps:

[0013] S121. Preprocessing, filtering the collected electrical signals to remove noise and interference;

[0014] S122. Reshape the electrical signal to ensure that the waveform and amplitude of the electrical signal meet the subsequent input requirements;

[0015] S123. Select a mixer and configure parameters according to the type and characteristics of the electrical signal;

[0016] S124. Shape the intermediate frequency signal to ensure that the width, amplitude and interval meet the subsequent requirements;

[0017] S125. Perform statistics on the shaped intermediate frequency signal and input it into the back-end for processing.

[0018] As one aspect of a method for analyzing a laser radar signal through intermediate frequency data of the present invention, S2 comprises the following steps:

[0019] S21. Clean the intermediate frequency data to obtain intermediate frequency data matching the target signal;

[0020] S22. After obtaining the intermediate frequency data, the system automatically counts the signal parameters and determines them through manual comparison;

[0021] S23. Analyze the repeatability of the statistically analyzed signal parameters and the signal parameters in the parameter library.

[0022] As one aspect of a method for analyzing a laser radar signal through intermediate frequency data of the present invention, the S21 comprises the following steps:

[0023] S211. Using a digital signal processor to clean the matching target signal;

[0024] S212. Utilize the real azimuth angle of the target signal to filter and obtain intermediate frequency data matching the target signal.

[0025] As one aspect of a method for analyzing a laser radar signal through intermediate frequency data of the present invention, the S22 comprises the following steps:

[0026] S221. Analyze and obtain the signal parameters in the intermediate frequency data using the automatic statistical algorithm of the signal parameters;

[0027] S222. Automatically compare the signal parameters obtained after statistics with the signal parameters in the signal parameter library. If there are duplicates, remove them. If there are no duplicates, continue;

[0028] S223. For non-repetitive signal parameters, manually analyze the corresponding intermediate frequency data to confirm its credibility. If it is unreliable, it will be eliminated, and if it is reliable, it will be retained.

[0029] As one aspect of a method for analyzing a laser radar signal through intermediate frequency data of the present invention, the S221 includes the following steps:

[0030] S2211. Standardize the cleaned data to make it meet the initial requirements of statistical analysis;

[0031] S2212. Extract features from the intermediate frequency signal and perform statistics on the center frequency, maximum amplitude and phase;

[0032] S2213. Count the number of occurrences of each frequency or amplitude value to form a frequency distribution table or histogram;

[0033] S2214. Calculate the mean and variance of the frequency and amplitude respectively to determine whether the signal parameters are valid;

[0034] S2215. Perform correlation analysis on multiple characteristic parameters to understand the degree of correlation of the characteristic parameters;

[0035] S2216. Output the results of the statistical analysis in the form of a report or table to facilitate subsequent analysis and processing;

[0036] S2217. Compare the statistically obtained signal parameters in pairs, remove signal parameters with the same parameters, and finally obtain new signal parameters.

[0037] As one aspect of a method for analyzing a laser radar signal through intermediate frequency data of the present invention, S3 comprises the following steps:

[0038] S31. Storing reliable signal parameters in a signal parameter library to form a signal parameter library for use in multiple fields;

[0039] S32. The control mechanism dynamically mobilizes and allocates radar resources according to the radar detection task requirements to improve the detection performance and anti-interference capability of the radar system;

[0040] S33. The feedback mechanism acts on the data selector to reduce interference signals while automatically updating the signal parameter library.

[0041] By adopting the above technical solution, the present invention has the following advantages:

[0042] The present invention provides a method for analyzing laser radar signals through intermediate frequency data. The electrical signal is converted into intermediate frequency data through a mixer; the intermediate frequency data is cleaned, and reliable signal parameters are stored in a signal parameter library. The feedback mechanism acts on a data selector, which greatly reduces the disadvantages of redundant information interference, makes data processing more efficient, and improves the accuracy of data information. The intermediate frequency data processing technology is combined to improve the performance of laser radar. The intermediate frequency technology reduces the complexity of data processing and improves data accuracy and stability through preprocessing and feature extraction. The laser radar system combined with intermediate frequency data processing shows stronger adaptability when dealing with extreme weather and complex geographical environments, and has a very broad development prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A flowchart of a method for analyzing laser radar signals through intermediate frequency data of the present invention;

[0044] Figure 2 A flow chart of obtaining the signal parameters of intermediate frequency data using an automatic statistical algorithm for signal parameters. DETAILED DESCRIPTION

[0045] The technical solution of the present invention is described in detail below in conjunction with the drawings in the specification. It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0046] Figure 1 A flowchart of a method for analyzing a laser radar signal through intermediate frequency data of the present invention is shown; a method for analyzing a laser radar signal through intermediate frequency data is specifically as follows Figure 1 As shown, the following steps are included:

[0047] S1. Capture the electrical signal through the detector and convert it into intermediate frequency data through the mixer;

[0048] Among them, S1 includes the following specific steps:

[0049] S11. Use the laser radar's transmitting device to emit a detection laser beam, receive the echo signal through the detector, and convert the optical signal into an electrical signal.

[0050] S12. When the electrical signal is transmitted to the data selector, the electrical signal is converted into intermediate frequency data through the mixer according to different detection channel input signals. Among them, the data selector has many signal channels, and the received signal selects the output channel. When the mixer channel is selected, the received signal will be converted, and the digital mixer multiplies the digital intermediate frequency signal and the orthogonal local oscillator signal generated by the digital control oscillator to down-convert it to zero intermediate frequency.

[0051] Wherein, S12 includes the following specific steps:

[0052] S121. Preprocessing, filtering the collected electrical signals to remove noise and interference;

[0053] S122. Reshape the electrical signal to ensure that the waveform and amplitude of the electrical signal meet the subsequent input requirements;

[0054] S123. Select a mixer and configure parameters according to the type and characteristics of the electrical signal;

[0055] S124. Shape the intermediate frequency signal to ensure that the width, amplitude and interval meet the subsequent requirements;

[0056] S125. Perform statistics on the shaped intermediate frequency signal and input it into the back-end for processing.

[0057] S2. Clean the intermediate frequency data; perform automatic statistical calculations on the cleaned data to obtain new signal parameters; and manually repeat and confirm the reliability of the signal parameters;

[0058] Among them, S2 includes the following specific steps:

[0059] S21. Clean the intermediate frequency data to obtain intermediate frequency data matching the target signal;

[0060] Wherein, S21 includes the following specific steps:

[0061] S211. Using a digital signal processor to clean the matching target signal;

[0062] S212. Utilize the real azimuth angle of the target signal to filter and obtain intermediate frequency data matching the target signal.

[0063] In a specific embodiment, data cleaning of the intermediate frequency data is specifically shown in Table 1 below:

[0064] Table 1: Data cleaning of intermediate frequency data

[0065]

[0066]

[0067] Among many laser radar signals, a laser radar signal is selected as the target signal; the true azimuth of the target signal at 12:00:01 is 15°, and the intermediate frequency data matching the target signal is obtained by screening using the true azimuth, as shown in Table 2 below:

[0068] Table 2: Intermediate frequency data of the selected targets

[0069]

[0070] S22. After obtaining the intermediate frequency data, the system automatically counts the signal parameters and determines them through manual comparison;

[0071] Wherein, S22 includes the following specific steps:

[0072] S221. Analyze and obtain the signal parameters in the intermediate frequency data using the automatic statistical algorithm of the signal parameters;

[0073] Among them, S221 includes the following steps: Figure 2 As shown:

[0074] S2211. Standardize the cleaned data to make it meet the initial requirements of statistical analysis;

[0075] S2212. Extract features from the intermediate frequency signal and perform statistics on the center frequency, maximum amplitude and phase;

[0076] S2213. Count the number of occurrences of each frequency or amplitude value to form a frequency distribution table or histogram;

[0077] S2214. Calculate the mean and variance of the frequency and amplitude respectively to determine whether the signal parameters are valid;

[0078] S2215. Perform correlation analysis on multiple characteristic parameters to understand the degree of correlation of the characteristic parameters;

[0079] S2216. Output the results of the statistical analysis in the form of a report or table to facilitate subsequent analysis and processing;

[0080] S2217. Compare the statistically obtained signal parameters in pairs, remove signal parameters with the same parameters, and finally obtain new signal parameters.

[0081] In a specific embodiment, according to the two dimensional data of frequency and bandwidth of the intermediate frequency data, the signal parameters in the intermediate frequency data are analyzed using an automatic statistical algorithm of signal parameters, as shown in Table 3 below.

[0082] Table 3: Signal parameters obtained by automatic statistics

[0083] Serial number Frequency (MHz) Bandwidth (MHz) 1. 456 3.5 2. 462 4.5

[0084] S222. Automatically compare the signal parameters obtained after statistics with the signal parameters in the signal parameter library. If there are duplicates, remove them. If there are no duplicates, continue;

[0085] In a specific embodiment, the newly statistically obtained signal parameters (Table 3) are automatically compared with the parameters of the signal parameter library (Table 4), and the non-repetitive signal parameters are analyzed and obtained as shown in Table 5 below.

[0086] Table 4: Signal parameter library

[0087] Serial number Frequency (MHz) Bandwidth (MHz) Lidar name 1. 456 3.5 A1

[0088] Table 5: Signal parameters that are not repeated in the signal parameter library

[0089] Serial number Frequency (MHz) Bandwidth (MHz) 2. 462 4.5

[0090] S223. For non-repetitive signal parameters, manually analyze the corresponding intermediate frequency data to confirm its credibility. If it is unreliable, it will be eliminated, and if it is reliable, it will be retained.

[0091] In a specific embodiment, for the signal parameters in Table 5, the intermediate frequency data corresponding to the signal parameters in Table 5 are manually analyzed to obtain that the signal parameters are credible and the radar name is A1. After confirmation, the signal parameters are shown in Table 6 below.

[0092] Table 6: Signal parameters after confirmation

[0093] Serial number Frequency (MHz) Bandwidth (MHz) Lidar name 1. 462 4.5 A1

[0094] S23. Analyze the repeatability of the statistically analyzed signal parameters and the signal parameters in the parameter library.

[0095] S3. The reliable signal parameters are stored in the signal parameter library. The control mechanism improves the detection performance and anti-interference ability of the radar system. The feedback mechanism acts on the data selector to reduce the interference signal while automatically updating the signal parameter library.

[0096] Among them, S3 includes the following specific steps:

[0097] S31. Storing reliable signal parameters in a signal parameter library to form a signal parameter library for use in multiple fields;

[0098] S32. The control mechanism dynamically mobilizes and allocates radar resources according to the radar detection task requirements to improve the detection performance and anti-interference capability of the radar system;

[0099] S33. The feedback mechanism acts on the data selector to reduce interference signals while automatically updating the signal parameter library.

[0100] Finally, it should be pointed out that although the present invention has been described with reference to the current specific embodiments, ordinary technicians in this technical field should realize that the above embodiments are only used to illustrate the present invention and are not used as a limitation of the present invention. Various equivalent changes or substitutions can be made without departing from the concept of the present invention. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present invention, they will fall within the scope of the claims of the present invention.

Claims

1. A method for analyzing laser radar signals through intermediate frequency data, characterized in that: The following steps are involved: S1. Capture the electrical signal through the detector and convert it into intermediate frequency data through the mixer; S2. Clean the intermediate frequency data; perform automatic statistical calculations on the cleaned data to obtain new signal parameters; and manually repeat and confirm the reliability of the signal parameters; S3. The reliable signal parameters are stored in the signal parameter library. The control mechanism improves the detection performance and anti-interference ability of the radar system. The feedback mechanism acts on the data selector to reduce the interference signal while automatically updating the signal parameter library.

2. The method for analyzing laser radar signals by intermediate frequency data according to claim 1, characterized in that: The S1 comprises the following steps: S11. The laser radar transmitting device emits a detection laser beam, and the detector receives the echo signal and converts the optical signal into an electrical signal; S12. When the electrical signal is transmitted to the data selector, it is converted into intermediate frequency data through a mixer according to different detection channel input signals.

3. The method for analyzing laser radar signals by intermediate frequency data according to claim 2, characterized in that: The S12 comprises the following steps: S121. Preprocessing, filtering the collected electrical signals to remove noise and interference; S122. Reshape the electrical signal to ensure that the waveform and amplitude of the electrical signal meet the subsequent input requirements; S123. Select a mixer and configure parameters according to the type and characteristics of the electrical signal; S124. Shape the intermediate frequency signal to ensure that the width, amplitude and interval meet the subsequent requirements; S125. Perform statistics on the shaped intermediate frequency signal and input it into the back-end for processing.

4. The method for analyzing laser radar signals by intermediate frequency data according to claim 1, characterized in that: The S2 comprises the following steps: S21. Clean the intermediate frequency data to obtain intermediate frequency data matching the target signal; S22. After obtaining the intermediate frequency data, the system automatically counts the signal parameters and determines them through manual comparison; S23. Analyze the repeatability of the statistically analyzed signal parameters and the signal parameters in the parameter library.

5. The method for analyzing laser radar signals by intermediate frequency data according to claim 4, characterized in that: The S21 comprises the following steps: S211. Using a digital signal processor to clean the matching target signal; S212. Utilize the real azimuth angle of the target signal to filter and obtain intermediate frequency data matching the target signal.

6. The method for analyzing laser radar signals by intermediate frequency data according to claim 4, characterized in that: The S22 comprises the following steps: S221. Analyze and obtain the signal parameters in the intermediate frequency data using the automatic statistical algorithm of the signal parameters; S222. Automatically compare the signal parameters obtained after statistics with the signal parameters in the signal parameter library. If there are duplicates, remove them. If there are no duplicates, continue; S223. For non-repetitive signal parameters, manually analyze the corresponding intermediate frequency data to confirm its credibility. If it is unreliable, it will be eliminated, and if it is reliable, it will be retained.

7. The method for analyzing laser radar signals through intermediate frequency data according to claim 6, characterized in that: The S221 includes the following steps: S2211. Standardize the cleaned data to make it meet the initial requirements of statistical analysis; S2212. Extract features from the intermediate frequency signal and perform statistics on the center frequency, maximum amplitude and phase; S2213. Count the number of occurrences of each frequency or amplitude value to form a frequency distribution table or histogram; S2214. Calculate the mean and variance of the frequency and amplitude respectively to determine whether the signal parameters are valid; S2215. Perform correlation analysis on multiple characteristic parameters to understand the degree of correlation of the characteristic parameters; S2216. Output the results of the statistical analysis in the form of a report or table to facilitate subsequent analysis and processing; S2217. Compare the statistically obtained signal parameters in pairs, remove signal parameters with the same parameters, and finally obtain new signal parameters.

8. The method for analyzing laser radar signals through intermediate frequency data according to claim 1, characterized in that: The S3 comprises the following steps: S31. Storing reliable signal parameters in a signal parameter library to form a signal parameter library for use in multiple fields; S32. The control mechanism dynamically mobilizes and allocates radar resources according to the radar detection task requirements to improve the detection performance and anti-interference capability of the radar system; S33. The feedback mechanism acts on the data selector to reduce interference signals while automatically updating the signal parameter library.

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