Very high frequency coherent scatter radar data product generation method and system

Abstract

The invention provides a very high frequency coherent scatter radar data product generation method and system, and the method comprises the steps: carrying out the multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherent accumulation, autocorrelation analysis, power spectrum calculation and parameter extraction of an ionized layer echo signal collected by a very high frequency coherent scatter radar; obtaining standardized processing data; based on the standardized processing data, generating a four-level hierarchical data product; performing whole-process quality control on the four-level data product; standard marking is carried out on the four-level data product subjected to quality control by adopting a unified space-time reference, and a very high frequency coherent scattering radar data product is output; by means of the method, full-chain standardized processing of ionosphere echo data from collection to product output can be achieved, and high-quality and high-compatibility data support is provided for ionosphere observation, space weather research and related engineering application.

Description

Technical Field

[0001] This invention relates to the field of ionospheric space weather observation technology, specifically to a method and system for generating VHF coherent scattering radar data products. Background Technology

[0002] Currently, the ionosphere, as a key component of the Earth's atmosphere, directly impacts the stability of technological systems such as radio communication, navigation and positioning, and satellite tracking and control due to the distribution, movement, and evolution of its inhomogeneities. The low-latitude ionosphere, influenced by the complex effects of the geomagnetic field, solar radiation, and atmospheric circulation, exhibits active inhomogeneity activity, making it a core target for ground-based monitoring of the space environment. Very High Frequency (VHF) coherent scattering radar, as the core equipment for low-latitude ionospheric observation, directly determines the application value of its data through the scientific rigor and standardization of its data processing and product generation.

[0003] However, existing VHF coherent scattering radar data processing and product generation technologies have many prominent problems, which severely restrict the availability and application scope of the data: The product system is incomplete and difficult to adapt to the needs of multiple users: existing solutions mostly only output raw IQ data or single power spectrum data, lacking a full-chain hierarchical system from raw data to processed data, application parameters and visualization products. It cannot simultaneously meet the needs of researchers for in-depth analysis of raw data and the needs of engineering users for quick use of intuitive parameters and visualization results, thus limiting the data application scenarios. The processing procedures are not standardized and the data consistency is poor: key processing steps such as radio frequency interference suppression, coherence accumulation, autocorrelation analysis and power spectrum calculation lack unified standards, core processing parameters are not clearly defined, and the processing procedures and parameter settings differ at different sites and at different times, resulting in insufficient data consistency and making it difficult to meet the research needs of multi-site joint analysis and long-term sequence comparison. The lack of a quality control mechanism results in insufficient data reliability: Existing technologies have limited means for data error correction, file format verification, and abnormal data identification, and have not formed a quality control system covering the entire data processing process. As a result, hardware errors, spectral leakage, and abnormal values ​​are easily left in the data, and the data reliability cannot meet the requirements of high-precision observation and application. Inconsistent spatiotemporal benchmarks and poor data compatibility: Non-standard time annotation formats and inconsistent spatial coordinate systems result in poor spatiotemporal correlation of observation data from different stations and time periods, making it difficult to effectively integrate them into the data system and thus hindering spatiotemporal correlation analysis across stations and time periods. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a method for generating VHF coherent scattering radar data products, comprising: Ionospheric echo signals were acquired using a very high frequency coherent scattering radar. The echo signal is sequentially subjected to multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherence accumulation, autocorrelation analysis, power spectrum calculation and parameter extraction to obtain standardized processed data. Based on the standardized processed data, a four-level hierarchical data product is generated, corresponding sequentially to the original data, processed data, application parameters, and visualization products. The four-level data products are subjected to full-process quality control to obtain quality-controlled four-level data products. The quality-controlled Level 4 data products are standardized and labeled using a unified spatiotemporal reference, and standardized VHF coherent scattering radar data products are output. The four-level hierarchical data products include raw echo information, spectral feature information, core application parameters, and intuitive visualization results.

[0005] Optionally, the VHF coherent scattering radar is adapted to preset hardware parameters and deployed with an antenna array to collect backscattered echo signals from inhomogeneities in the E and F regions of the ionosphere. The preset hardware parameters include one or more of the following: operating frequency, transmission power, pulse parameters, beamwidth, and detection range configuration; The pulse parameters include one or more of the following: pulse width, duty cycle, and pulse repetition frequency; The antenna array is an array structure consisting of multiple rows and groups of three-element Yagi antennas.

[0006] Optionally, radio frequency interference suppression is performed on the signal synthesized from multiple channels, including: Fixed interference signals outside the operating frequency band of the VHF coherent scattering radar are filtered out by bandpass filtering; Random interference signals in the echo signal after multi-channel signal synthesis are suppressed by adaptive filtering.

[0007] Optionally, the signal after radio frequency interference suppression is subjected to IQ sampling and digital filtering, including: The signal after radio frequency interference suppression is subjected to high-speed IQ sampling to obtain in-phase I signal and quadrature Q signal; The sampled signal is downsampled using a preset decimation factor, and then combined with matched filtering and amplitude-phase weighting to output a single-channel IQ echo signal.

[0008] Optionally, coherent accumulation of the single-channel IQ echo signal includes: Obtain the operating mode of the VHF coherent scattering radar; When the operating mode is in zone E mode, a first preset number of pulses are used for coherent accumulation; When the operating mode is in the F-zone mode, a second preset number of pulses are used for coherent accumulation; When the operating mode is in scanning mode, a third preset number of pulses are used for coherent accumulation; The coherent accumulation is achieved by superimposing signal energy through arithmetic summation.

[0009] Optionally, autocorrelation analysis, power spectrum calculation, and parameter extraction are performed on the coherently accumulated signal, including: The coherently accumulated signal is partitioned according to a preset distance gate partitioning rule, and the autocorrelation function of the signal within each distance gate is calculated; the time delay range of the autocorrelation function is adapted to the pulse width. The power spectrum is obtained by performing a discrete Fourier transform on the autocorrelation function. The power spectrum was fitted with a Gaussian function to extract core application parameters. The core application parameters include one or more of the following: echo intensity, signal-to-noise ratio, spectral width, and Doppler velocity.

[0010] Optionally, the step of performing full-process quality control on the Level 4 data products to obtain quality-controlled Level 4 data products includes: The error-corrected Level 4 data product is obtained by performing error correction on the Level 4 data product. The error-corrected Level 4 data product is then subjected to file verification to obtain a file-verified Level 4 data product. Anomaly identification is performed on the Level 4 data product after file verification, and numerical anomalies that exceed the preset parameter value range are marked to obtain a Level 4 data product that has passed quality control. The error correction includes: hardware sampling error correction and spectrum leakage error correction; The hardware sampling error correction includes: AD sampling nonlinearity correction and antenna phase deviation correction; The file verification includes: filename format verification, file header information verification, file size verification, and data point count verification.

[0011] Optionally, the unified spatiotemporal reference includes a time reference, a spatial reference, and a velocity reference; The time base adopts Coordinated Universal Time (UTC) format and is used to mark the time of product file names and file contents; The spatial reference uses the geographic coordinate system GEO to mark the latitude and longitude of the stations and the geodetic system WGS84 to mark the altitude. The velocity reference is the Doppler velocity, marked with the direction away from the VHF coherent scattering radar as the positive direction.

[0012] Based on the same inventive concept, the present invention also provides a VHF coherent scattering radar data product generation system, comprising: The signal acquisition module is used to acquire ionospheric echo signals through a very high frequency coherent scattering radar. The standardization processing module is used to sequentially perform multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherence accumulation, autocorrelation analysis and power spectrum calculation and parameter extraction on the echo signal to obtain standardized processed data. The data processing module is used to generate a four-level hierarchical data product based on the standardized processed data, which sequentially corresponds to the original data, processed data, application parameters, and visualization products. The quality control module is used to perform full-process quality control on the Level 4 data products to obtain Level 4 data products that have undergone quality control. The product output module is used to standardize and annotate the quality-controlled Level 4 data products using a unified spatiotemporal reference, and output standardized VHF coherent scattering radar data products. The four-level hierarchical data products include raw echo information, spectral feature information, core application parameters, and intuitive visualization results.

[0013] Optionally, the VHF coherent scattering radar is adapted to preset hardware parameters and deployed with an antenna array to collect backscattered echo signals from inhomogeneities in the E and F regions of the ionosphere. The preset hardware parameters include one or more of the following: operating frequency, transmission power, pulse parameters, beamwidth, and detection range configuration; The pulse parameters include one or more of the following: pulse width, duty cycle, and pulse repetition frequency; The antenna array is an array structure consisting of multiple rows and groups of three-element Yagi antennas.

[0014] Optionally, the standardization processing module includes: an interference suppression submodule, specifically including: A fixed interference filtering unit is used to filter out fixed interference signals outside the operating frequency band of the VHF coherent scattering radar by bandpass filtering; The random interference filtering unit is used to suppress random interference signals in the echo signal after multi-channel signal synthesis through adaptive filtering.

[0015] Optionally, the standardization processing module includes: a digital filtering submodule, specifically including: The high-speed sampling unit is used to perform high-speed IQ sampling on the signal after radio frequency interference suppression to obtain in-phase I signals and quadrature Q signals; The downsampling unit is used to downsample the sampled signal using a preset decimation factor, and combined with matched filtering and amplitude and phase weighting, outputs a single-channel IQ echo signal.

[0016] Optionally, the standardization processing module includes: a coherent accumulation submodule, specifically including: The mode acquisition unit is used to acquire the operating mode of the VHF coherent scattering radar. The first accumulation unit is used to perform coherent accumulation using a first preset number of pulses when the operating mode is in the E-zone mode. The second accumulation unit is used to perform coherent accumulation using a second preset number of pulses when the operating mode is in the F-zone mode. The third accumulation unit is used to perform coherent accumulation using a third preset number of pulses when the operating mode is in scanning mode. The coherent accumulation is achieved by superimposing signal energy through arithmetic summation.

[0017] Optionally, the standardization processing module includes: a parameter extraction submodule, specifically including: The signal partitioning unit is used to partition the coherently accumulated signal according to a preset distance gate partitioning rule and calculate the autocorrelation function of the signal within each distance gate; the time delay range of the autocorrelation function is adapted to the pulse width. The function transformation unit is used to perform a discrete Fourier transform on the autocorrelation function to obtain the power spectrum; The signal fitting unit is used to fit the power spectrum with a Gaussian function and extract core application parameters. The core application parameters include one or more of the following: echo intensity, signal-to-noise ratio, spectral width, and Doppler velocity.

[0018] Optionally, the quality control module includes: The error correction submodule is used to perform error correction on the Level 4 data product to obtain the Level 4 data product after error correction. The file verification submodule is used to perform file verification on the error-corrected Level 4 data product to obtain the file-verified Level 4 data product. The anomaly identification submodule is used to identify anomalies in the Level 4 data products after file verification, mark numerical anomalies that exceed the preset parameter value range, and obtain Level 4 data products that have passed quality control. The error correction includes: hardware sampling error correction and spectrum leakage error correction; The hardware sampling error correction includes: AD sampling nonlinearity correction and antenna phase deviation correction; The file verification includes: filename format verification, file header information verification, file size verification, and data point count verification.

[0019] Optionally, the unified spatiotemporal reference includes: a time reference, a spatial reference, and a velocity reference; The time base adopts Coordinated Universal Time (UTC) format and is used to mark the time of product file names and file contents; The spatial reference uses the geographic coordinate system GEO to mark the latitude and longitude of the stations and the geodetic system WGS84 to mark the altitude. The velocity reference is the Doppler velocity, marked with the direction away from the VHF coherent scattering radar as the positive direction.

[0020] In another aspect, the present invention also provides an electronic device, comprising: at least one processor and a memory; the memory and the processor are connected via a bus; The memory is used to store one or more programs; When the one or more programs are executed by the at least one processor, a method for generating VHF coherent scattering radar data products as described above is implemented.

[0021] In another aspect, the present invention also provides a computer device readable storage medium having an executable program stored thereon, wherein when the executable program is executed, it implements a method for generating VHF coherent scattering radar data products as described above.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a method and system for generating VHF coherent scatter radar data products, comprising: acquiring ionospheric echo signals through VHF coherent scatter radar; sequentially performing multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherent accumulation, autocorrelation analysis, and power spectrum calculation and parameter extraction on the echo signals to obtain standardized processed data; generating a four-level hierarchical data product based on the standardized processed data, corresponding sequentially to original data, processed data, application parameters, and visualization products; performing full-process quality control on the four-level data products to obtain quality-controlled four-level data products; standardizing and annotating the quality-controlled four-level data products using a unified spatiotemporal reference to output standardized VHF coherent scatter radar data products; wherein, the four-level hierarchical data products respectively include original echo information, spectral characteristic information, core application parameters, and intuitive visualization results. This invention utilizes VHF coherent scattering radar to directionally acquire ionospheric echo signals, ensuring the relevance and effectiveness of the data source. By sequentially performing standardized processing steps such as multi-channel signal synthesis and radio frequency interference suppression on the echo signals, the invention guarantees the standardization and consistency of data processing. The generation of four-level hierarchical data products—corresponding sequentially to raw data, processed data, application parameters, and visualization products—covers the differentiated needs of various users. Full-process quality control of the four-level data products effectively improves data reliability and accuracy. Standardized annotation using a unified spatiotemporal benchmark facilitates cross-site spatiotemporal correlation and integration compatibility of data. Therefore, the method of this invention enables standardized processing of ionospheric echo data from acquisition to product output, providing high-quality and highly compatible data support for ionospheric observation, space weather research, and related engineering applications. Attached Figure Description

[0023] Figure 1 A flowchart illustrating a method for generating VHF coherent scattering radar data products provided by the present invention; Figure 2 A schematic diagram of the overall framework of a method for generating VHF coherent scattering radar data products provided by the present invention; Figure 3 A schematic diagram illustrating a method for generating VHF coherent scattering radar data products, provided as a specific embodiment of the present invention; Figure 4 A schematic diagram of the antenna array distribution for a method of generating VHF coherent scattering radar data products provided in a specific embodiment of the present invention; Figure 5 A schematic diagram of the structural composition of a VHF coherent scattering radar data product generation system provided by the present invention; Figure 6 This is a schematic diagram of the structure of an electronic device provided by the present invention. Detailed Implementation

[0024] This invention proposes a method, system, device, and medium for generating VHF coherent scattering radar data products. The specific embodiments of this invention will be further described in detail below with reference to the accompanying drawings.

[0025] Example 1: This invention provides a method for generating VHF coherent scattering radar data products, the flowchart of which is shown below. Figure 1 As shown, it includes: Step 1: Acquire ionospheric echo signals using VHF coherent scattering radar; Step 2: Perform multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherence accumulation, autocorrelation analysis, power spectrum calculation and parameter extraction on the echo signal in sequence to obtain standardized processed data; Step 3: Based on the standardized processed data, generate a four-level hierarchical data product that corresponds sequentially to the original data, processed data, application parameters, and visualization products; Step 4: Perform full-process quality control on the Level 4 data products to obtain Level 4 data products that have undergone quality control; Step 5: Standardize and annotate the quality-controlled Level 4 data products using a unified spatiotemporal reference, and output standardized VHF coherent scattering radar data products. The four-level hierarchical data products include raw echo information, spectral feature information, core application parameters, and intuitive visualization results.

[0026] In one implementation, the VHF coherent scattering radar in step 1 above is adapted to preset hardware parameters and an antenna array is deployed to collect backscattered echo signals from inhomogeneous bodies in the E and F regions of the ionosphere. The preset hardware parameters may include one or more of the following: operating frequency, transmit power, pulse parameters, beamwidth, and detection range configuration; The pulse parameters may include one or more of the following: pulse width, duty cycle, and pulse repetition frequency; The antenna array can be an array structure composed of multiple rows and multiple groups of three-element Yagi antennas; For example, in this implementation, the antenna array can be deployed in an east-west oriented three-row structure, with each row containing 12 groups of three-element Yagi antennas, and the antenna element spacing... ( With a signal wavelength of 47.5MHz (approximately 6.31m), it can form a 10°×22° beam. The peak power of the VHF coherent scatter radar transceiver system can preferably be set to 48KW, the sampling rate of the receiver can be set to 40MHz, the bit depth of the AD converter can be set to 16bit (16bit each for I / Q), and the bandwidth of the RF filter can be set to 1MHz (corresponding to a center frequency of 47.5MHz). In this implementation, the VHF coherent scattering radar is adapted to preset hardware parameters including operating frequency, transmit power, pulse parameters (including pulse width, duty cycle, and pulse repetition frequency), beamwidth, and detection range. This allows for targeted matching of the detection requirements of inhomogeneities in the E and F regions of the ionosphere. Differentiated pulse parameters balance detection resolution and efficiency. The array structure composed of multiple rows and groups of three-element Yagi antennas ensures detection coverage and directional accuracy, and improves the reception strength and directionality of echo signals.

[0027] In one implementation, the process of suppressing radio frequency interference in the multi-channel signal synthesized signal in step 2 above may include: Fixed interference signals outside the operating frequency band of the VHF coherent scattering radar are filtered out by bandpass filtering; Random interference signals in the echo signal after multi-channel signal synthesis are suppressed by adaptive filtering; In this implementation, bandpass filtering can filter out fixed interference signals (such as broadcast signals) outside the operating frequency band of VHF coherent scatter radar, thus isolating the echo signal from non-target frequency band interference at the source. Then, adaptive filtering is used to specifically suppress the random interference signals remaining after multi-channel signal synthesis, which can make up for the shortcomings of bandpass filtering in suppressing dynamic and sudden interference. The two form a synergistic and complementary interference suppression system, which can not only ensure that fixed interference is effectively isolated, but also dynamically track and weaken the impact of random interference, ensuring that the original amplitude and phase information of the echo signal is not lost, while significantly improving the signal-to-noise ratio.

[0028] In one implementation, the process of performing IQ sampling and digital filtering on the signal that has undergone radio frequency interference suppression may include: The signal after radio frequency interference suppression is subjected to high-speed IQ sampling to obtain in-phase I signal and quadrature Q signal; The sampled signal is downsampled using a preset decimation factor, and then combined with matched filtering and amplitude-phase weighting to output a single-channel IQ echo signal. In this implementation, high-speed IQ sampling of the signal after radio frequency interference suppression accurately captures the in-phase I and quadrature Q signals of the echo signal, completely preserving the original amplitude and phase information of the echo signal and avoiding signal feature loss caused by the sampling process. Downsampling of the sampled signal using a preset decimation factor effectively reduces the amount of sampled data without losing key signal information, reducing computational power consumption in subsequent data processing and balancing processing efficiency and data integrity. Furthermore, by combining matched filtering and amplitude-phase weighting, residual interference can be further filtered out and the signal-to-noise ratio improved through matched filtering, while signal consistency is optimized through amplitude-phase weighting. The final output is a high-quality single-channel IQ echo signal, avoiding the impact of redundant signals or signal distortion on subsequent coherent accumulation and parameter extraction steps, ensuring the accuracy of standardized data processing, and providing reliable intermediate processing data support for the generation of four-level hierarchical data products.

[0029] In one implementation, the process of coherently accumulating the single-channel IQ echo signal may include: Obtain the operating mode of the VHF coherent scattering radar; When the operating mode is in zone E mode, a first preset number of pulses are used for coherent accumulation; When the operating mode is in the F-zone mode, a second preset number of pulses are used for coherent accumulation; When the operating mode is in scanning mode, a third preset number of pulses are used for coherent accumulation; The coherent accumulation is achieved by superimposing signal energy through arithmetic summation; For example, in this implementation, the parameters for the running mode can be set as shown in Table 1 below: Table 1 Operating Mode Parameter Table

[0030] In this implementation, by acquiring the operating mode of the VHF coherent scattering radar, first, second, and third preset numbers of pulses are configured for coherent accumulation in the E-zone mode, F-zone mode, and scanning mode. This can accurately adapt to the detection requirements of different operating modes. Specifically, the E-zone and F-zone modes focus on precise detection of specific ionospheric regions, while the scanning mode emphasizes large-area coverage detection. The differentiated pulse number configuration can ensure the detection accuracy of the E-zone and F-zone modes while taking into account the detection efficiency of the scanning mode, avoiding insufficient accuracy or wasted computing power caused by a single pulse number configuration. By using arithmetic summation to achieve signal energy superposition, the effective energy of a single IQ echo signal can be aggregated in a simple and efficient manner, significantly improving the signal-to-noise ratio, reducing the interference of random noise on signal characteristics, and preventing weak echo signals from being masked by noise. It can also reduce the computing power consumption of the accumulation process and ensure processing efficiency, ultimately outputting an accumulated signal with concentrated energy and clear characteristics.

[0031] In one implementation, the process of performing autocorrelation analysis, power spectrum calculation, and parameter extraction on the coherently accumulated signal may include: The coherently accumulated signal is partitioned according to a preset distance gate partitioning rule, and the autocorrelation function of the signal within each distance gate is calculated; the time delay range of the autocorrelation function is adapted to the pulse width. The power spectrum is obtained by performing a discrete Fourier transform on the autocorrelation function. The power spectrum was fitted with a Gaussian function to extract core application parameters. The core application parameters include one or more of the following: echo intensity, signal-to-noise ratio, spectral width, and Doppler velocity; In this implementation, by partitioning the coherently accumulated signal according to a preset range gate division rule, echo signals at different detection distances can be accurately located, avoiding mutual interference between signals from different range segments and ensuring the independence and integrity of signal characteristics within each range gate. Combined with the settings for the time delay range and pulse width adaptation of the autocorrelation function, the temporal correlation characteristics of the signal can be accurately captured, avoiding autocorrelation calculation deviations caused by inappropriate time delay ranges and ensuring the accuracy of the autocorrelation function. The power spectrum is obtained by performing a discrete Fourier transform on the autocorrelation function, converting the time-domain signal into a frequency-domain signal, clearly presenting the spectral distribution characteristics of the ionospheric inhomogeneity echo signal, providing... The core parameter extraction provides an intuitive and reliable analytical framework. By employing Gaussian function fitting to the power spectrum, it effectively avoids power spectrum noise interference and accurately extracts core application parameters such as echo intensity, signal-to-noise ratio, spectral width, and Doppler velocity. This ensures the high accuracy and stability of the extracted parameters, which cover key characteristic parameters required for ionospheric observation. It can be directly adapted to the needs of scientific research analysis and engineering applications, providing accurate and reliable core data support for the generation of application parameter-based and visualization-based products in the four-level hierarchical data product system. Simultaneously, it ensures the integrity and effectiveness of standardized data processing, further enhancing the practicality and scientific rigor of the entire data product generation method.

[0032] In one implementation, step 4 above, which involves performing full-process quality control on the Level 4 data product to obtain a quality-controlled Level 4 data product, may include: The error-corrected Level 4 data product is obtained by performing error correction on the Level 4 data product. The error-corrected Level 4 data product is then subjected to file verification to obtain a file-verified Level 4 data product. Anomaly identification is performed on the Level 4 data product after file verification, and numerical anomalies that exceed the preset parameter value range are marked to obtain a Level 4 data product that has passed quality control. The error correction includes: hardware sampling error correction and spectrum leakage error correction; The hardware sampling error correction includes: AD sampling nonlinearity correction and antenna phase deviation correction; The file verification includes: filename format verification, file header information verification, file size verification, and data point count verification; This implementation method achieves multi-dimensional quality control of Level 4 data products by conducting full-process quality control, including error correction, file verification, and anomaly identification. Specifically, hardware sampling error correction and spectrum leakage error correction can accurately eliminate systematic errors generated in the hardware acquisition and data processing stages, restoring the original true characteristics of the data and preventing errors from propagating within the product and affecting parameter accuracy. Full-dimensional file verification, including filename format, header information, file size, and data point count, strictly ensures the standardization, integrity, and readability of Level 4 data product files, preventing issues caused by inconsistent file formats, missing information, or abnormal data point counts. Product incompatibility and unresolved issues; by identifying and marking numerical anomalies that exceed the preset parameter range, invalid outliers in the data can be accurately filtered out, preventing abnormal data from misleading subsequent scientific research analysis and engineering applications. Ultimately, a closed-loop quality control system is formed, encompassing the entire chain from the data itself to the file format and numerical characteristics. This effectively improves the accuracy, reliability, and standardization of Level 4 data products, prevents unqualified data from entering the subsequent standardization and annotation process, ensures the effectiveness of standardization and annotation, and guarantees the quality of the final output of standardized VHF coherent scatter radar data products. This allows the product to meet the high-precision and high-requirement application scenarios such as multi-site joint analysis and long-term sequence comparison.

[0033] In one implementation, the unified spatiotemporal reference in step 5 above may include: a time reference, a spatial reference, and a velocity reference; The time base can be in Coordinated Universal Time (UTC) format, used to mark the time of product file names and file content; The spatial reference can be marked with the latitude and longitude of the station using the geographic coordinate system GEO, or with the elevation using the geodetic surveying system WGS84; The velocity reference can be a Doppler velocity marked with the direction away from the VHF coherent scattering radar as the positive direction; In this implementation, a unified three-dimensional spatiotemporal benchmark of time, space, and velocity is set for Level 4 data products, achieving standardized data annotation from multiple dimensions. The time benchmark uses Coordinated Universal Time (UTC) format to synchronously annotate product file names and contents, effectively ensuring precise time alignment of observation data from different time periods and stations, avoiding time series analysis deviations caused by inconsistent time formats, and guaranteeing the consistency of data time series characteristics. The spatial benchmark uses the Geographic Geometry (GEO) coordinate system to annotate station latitude and longitude, and the Geodetic Surveying System (WGS84) to annotate altitude, unifying the geospatial annotation system, eliminating spatial location errors caused by different coordinate system conversions, and ensuring the spatial correlation and location accuracy of multi-site data. The velocity benchmark annotates Doppler velocity with the direction away from VHF coherent scattering radar as the positive direction, enabling… This approach unifies the dimensions and direction definitions of velocity parameters, avoiding errors in parameter comparison and integration caused by inconsistent velocity annotation standards. It ensures the comparability of velocity characteristics, and the synergistic effect of the three-dimensional benchmark allows the quality-controlled Level 4 data products to form a unified annotation standard. This completely solves the problem of seamless integration and joint analysis of cross-time period and cross-site data caused by the inconsistency of traditional spatiotemporal benchmarks. At the same time, the standardized annotation format is highly compatible with the overall data management needs of multi-site ionospheric observation systems such as the Meridian Project. This ensures that the final output of standardized VHF coherent scatter radar data products has good interoperability, comparability, and integration. It can directly support high-precision scientific research and engineering applications such as multi-site joint analysis and large-scale spatiotemporal evolution research of the ionosphere, further expanding the application scope of data products and enhancing the overall application value of data products.

[0034] In summary, this invention addresses the prominent problems in existing VHF coherent scatter radar data processing and product generation technologies, such as incomplete product systems, non-standardized processing procedures, lack of quality control mechanisms, and inconsistent spatiotemporal references. It proposes a method for generating VHF coherent scatter radar data products, the overall framework of which is shown in the diagram below. Figure 2 As shown, echo signals from the ionosphere in regions E and F are acquired directionally using VHF coherent scattering radar, relying on the frame Figure 2The method described herein employs a coherent workflow involving multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherent accumulation, autocorrelation analysis, and power spectrum calculation and parameter extraction. This workflow sequentially generates intermediate processing results such as beam IQ, echo power spectrum, and power spectrum parameters. Ultimately, it constructs a four-level hierarchical data product comprising raw data (beam IQ records), processed data (echo power spectrum), application parameters (power spectrum parameters), and a visualization product (quick view). Through end-to-end quality control including error correction, document verification, and anomaly identification, as well as standardized annotation using a unified three-dimensional spatiotemporal benchmark of time, space, and velocity, the entire chain of standardized processing of ionospheric echo data from acquisition to product output is achieved. The method of this invention effectively improves the accuracy, consistency, reliability, and compatibility of data. It meets the needs of researchers for in-depth analysis of raw data such as beam IQ and also satisfies the needs of engineering users for rapid use of intuitive results such as power spectrum parameters and quick views. This provides high-quality data support for multi-site joint analysis, ionospheric observation, space weather research, and related engineering applications.

[0035] Example 2: The implementation process of the VHF coherent scattering radar data product generation method proposed in this invention is illustrated by a specific embodiment, as shown in the detection schematic diagram. Figure 3 As shown, the steps include: Step S1: Signal Acquisition (starting from time T0) The VHF coherent scattering radar radiates a 47.5MHz pulse signal according to the F-zone mode parameters. The antenna array receives backscattered echoes from inhomogeneous bodies in the F-zone within a range of 80-850km. 36 analog signals are transmitted to the equipment room via a feeder. A schematic diagram of the antenna array distribution is shown below. Figure 4 As shown, the parameter settings for the VHF coherent scattering radar are as follows: Power and pulse parameters: Peak power 48KW; Maximum duty cycle 10% (Gaussian pulse) / 15% (coded pulse); PRF50 / 100Hz; Pulse width 0.66us-200us (3.33us in area E, 13.33us in area F). Beam and detection range: Beamwidth 10° (east-west) × 22° (vertical); Number of beam positions 5 (±40°, ±20°, 0°); Detection range 80-850km; Range resolution 0.5km (E zone) / 2km (F zone); Time resolution 2min (E / F zone) / 5min (scanning mode).

[0036] Step S2: Multichannel synthesis (T0+1s) The 36 signals are combined into 6 channels through a power distribution network. Each channel is then filtered (e.g., 47.5±0.5MHz) and amplified with low noise (e.g., gain 30dB) before being transmitted to the receiver. Step S3: Radio Frequency Interference Suppression (T0+2s) Bandpass filtering: filters out fixed interference below 47MHz and above 48MHz (such as broadcast signals); Adaptive filtering: Based on the LMS algorithm (Least Mean Square algorithm), random interference is suppressed, and the interference signal is attenuated from -30dBm to below -60dBm; Step S4: IQ sampling and digital filtering (T0+5s) IQ sampling: The receiver samples 6 signals at 40MHz to obtain I / Q quadrature data (phase difference 90°), and the sampling time is 102.4s (corresponding to 10240 PRF cycles). PRF refers to pulse repetition frequency. Digital filtering: The sample is downsampled to a baseband bandwidth of 1MHz by a factor of 40, and combined with Hamming window matched filtering and amplitude and phase weighting to output one channel of IQ data with a data volume of about 240MB. This step can reduce the data volume and improve the signal-to-noise ratio. Step S5: Coherent accumulation (T0+10s) The number of accumulated pulses is adjusted according to the operating mode. The 1MHz baseband IQ data is arithmetically summed according to the PRF period (10ms). In E / F area mode, 10240 pulses (PRF 100Hz) are accumulated, and in scanning mode, 5120 pulses (PRF 50Hz) are accumulated, increasing the signal-to-noise ratio from 10dB to about 50dB. The signal energy is superimposed by arithmetic summation, and the signal-to-noise ratio improvement factor is proportional to the square root of the number of accumulated pulses.

[0037] Step S6: Autocorrelation analysis (T0+15s) The autocorrelation function is calculated for the echo signals from gates at different distances, and the corresponding settings are as follows: Distance gate division: starting distance 90km, ending distance 180km (E zone) / 850km (F zone), gate width 0.5km (E zone) / 2km (F zone). Autocorrelation calculation: The time delay range is 2-3 times the pulse width, the number of time delay sampling points is 32-64, and the time delay interval matches the power spectrum frequency range; specifically, the autocorrelation function of each distance gate is calculated for a time delay of 0-30us (i.e., 3 times the pulse width), with 32 time delay sampling points and an interval of 1μs.

[0038] Step S7: Power spectrum calculation and parameter extraction (T0+20s) The autocorrelation function is calculated from the echo signals of gates at different distances, as follows: Power spectrum calculation: Perform a 1024-point DFT (Discrete Fourier Transform) on the autocorrelation function to obtain the power spectrum from -500 to 500 Hz (frequency resolution of 1 Hz); Parameter extraction: The power spectrum was fitted using a Gaussian function, and four core parameters were extracted to obtain the echo intensity (the frequency domain integral value of the power spectrum, in dBmW), signal-to-noise ratio (the logarithmic value of the ratio of signal power to noise power, in dB), spectral width (the 3dB bandwidth of the power spectrum, in Hz), and Doppler velocity (the radial velocity converted from the frequency corresponding to the spectral peak, positive when farther away from the radar, in m / s) for 385 range gates. Step S8: Level 4 Product Generation (T0+30s) Level L0 (BIQR): Stored by distance gate and I / Q, generating a binary file named "SJ001_VHFR01_BIQR_L0_02H_20240101000000_V01.00.dat" (SJ001 is the station code), with a file size of 12GB (1 file every 2 hours). Level L1 (ECPS): Stored by time, distance, and frequency, generating a 15MB binary file named "SJ001_VHFR01_ECPS_L1_02H_20240101000000_V01.00.dat"; Level L2 (PSPP): The data is stored in blocks according to wave position, time, distance, and parameters as an ASCII file named "SJ001_VHFR01_PSPP_L2_DAY_20240101000000_V01.00.TXT", with a file size of 1.5MB (1 file per day). L2Q level (SPQP): Generate a PNG quick view named "SJ001_VHFR01_SPQP_L2Q_DAY_20240101000000_V01.00.png", containing 4 sub-images, with a size of 1390×820 pixels; The four product levels are L0, L1, L2, and L2Q. The specific details of L0 are shown in Table 2 below: Table 2 L0 Level Product Construction Contents Table level name Subclass coding Core Features Organizational methods Naming Rules L0 Beam IQ Recording BIQR AD sampling values ​​(unitless); time resolution 2 / 5 min; distance resolution 150 m; distance range 80-180 / 850 km Custom binary file; split every 2 hours (encoded 02H); single file 12GB; stored by distance gate -I / Q SJ001_VHFR01_BIQR_L0_02H_20240101000000_V01.00.dat

[0039] The specific details of L1 are shown in Table 3 below: Table 3 L1 Level Product Construction Contents Table level name Subclass coding Core Features Organizational methods Naming Rules L0 Beam IQ Recording BIQR AD sampling values ​​(unitless); time resolution 2 / 5 min; distance resolution 150 m; distance range 80-180 / 850 km Custom binary file; split every 2 hours (encoded 02H); single file 12GB; stored by distance gate -I / Q SJ001_VHFR01_BIQR_L0_02H_20240101000000_V01.00.dat

[0040] The specific details of L2 are shown in Table 4 below: Table 4 L2 Level Product Construction Contents Table level name Subclass coding Core Features Organizational methods Naming Rules L2 Power spectral parameters PSPP Echo intensity (-100~100dBmw), signal-to-noise ratio (0~100dB), spectral width (0~100Hz), Doppler velocity (-200~200m / s) Custom ASCII file; daily segmentation (encoded DAY); single file size 1.5MB; stored in blocks according to "wavelength-time-distance-parameter". SJ001_VHFR01_PSPP_L2_DAY_20240101000000_V01.00.TXT

[0041] The specific details of L2Q are shown in Table 5 below: Table 5 L2Q Level Product Construction Contents Table level name Subclass coding Core Features Organizational methods Naming Rules L2Q Power Spectrum Parameter Quick View SPQP Pseudo-color encoding; horizontal axis: time (24h); vertical axis: distance (80-180 / 850km); size: 1390×820 pixels PNG file; daily segmentation (encoded DAY); single file 12MB; TXT information blocks store auxiliary information. SJ001_VHFR01_SPQP_L2Q_DAY_20240101000000_V01.00.png

[0042] Step S9: Quality Control (T0+35s) Error correction: Corrects AD sampling nonlinearity error (≤3%) and power spectrum leakage (leakage energy ≤5%). File verification: Verify that L0 level files have the name "BIQR_L0_02H", the file header contains "Freq:47.5MHz", and the file size is 12GB±5%. If the verification passes, mark it as "Normal (T)". Anomaly identification: Mark outliers with Doppler velocities > 200 m / s, analyze echo intensity trends, and mark abrupt changes > 30 dB without physical cause as "suspicious". Record the quality information in the "xxx record table". The specific details of the above three-level quality control mechanism are shown in Table 6: Table 6. Full-process quality control mechanism control level Control Content Specific operations Level 1 (Error Correction) Hardware error and processing error correction 1. Hardware error: Correcting AD sampling nonlinearity and antenna phase deviation (error ≤ ±5%); 2. Processing error: Adding a Hanning window to suppress DFT spectral leakage (leakage energy ≤ 5%). Level 2 (Document Verification) Format verification, integrity verification 1. Format verification: Verify the filename (whether it conforms to the rules) and file header (whether it contains required fields such as quality markers); 2. Integrity verification: Check the file size (e.g., L0 level 12GB±5%) and the number of data points (e.g., L1 level distance gate 200 / 385). Level 3 (Anomaly Detection) Identification of numerical anomalies and trend anomalies; quality records 1. Numerical anomalies: Mark parameters that are out of range (e.g., Doppler velocity > 200 m / s); 2. Trend anomalies: Analyze sudden changes in sliding window parameters (e.g., echo intensity sudden change > 30 dB with no physical cause); 3. Quality recording: Store the results in a data recording table.

[0043] The contents of the unified spatiotemporal reference are shown in Table 7: Table 7 Spatiotemporal Reference Benchmark Category Specific standards Application scenarios Time base Coordinated Universal Time (UTC) is used; the time format is accurate to the second (YYYYMMDDhhmmss). Product file name, time stamp in file content Spatial reference 1. Site location: GEO coordinates for latitude and longitude, WGS84 coordinates for elevation (e.g., Shuangjiang station: 99.783°E, 23.483°N, 1058m); 2. Detection range: Slant distance (from target to equipment installation location); 3. Wavefront / Velocity: Wavefront is marked from west to east (0° is the center); Doppler velocity is positive when it is further away from the radar. 1. Site information labeling; 2. Spatial correlation of probe data; 3. Comparative analysis of multi-site data.

[0044] Step S10: Visualize the drawing Generate PNG / JPG format quick view based on power spectrum parameters Layout: A single image can contain 4 sub-images (echo intensity time-distance, signal-to-noise ratio-time-distance, spectral width-time-distance, Doppler velocity-time-distance); Size: 1390 (vertical) × 820 (horizontal) pixels, data area 400 × 820 pixels, using pseudo-color encoding parameter values; The above specific embodiments, based on clearly defining the hardware parameters of the VHF coherent scatter radar (such as 47.5MHz operating frequency, 48KW peak power, and 10°×22° beamwidth), refine the time nodes and operational standards for each processing step (such as bandpass filtering frequency band, LMS algorithm interference suppression, and 40MHz). The invention fully verifies the feasibility and effectiveness of its method by implementing IQ sampling, differentiated coherent accumulation pulse count, standardized naming rules and storage formats for Level 4 data products, and end-to-end quality control and unified spatiotemporal benchmark labeling. Practice shows that the method can accurately acquire echo signals from inhomogeneous bodies in the E and F regions of the ionosphere, effectively suppress fixed and random radio frequency interference (interference attenuation ≥30dB), and significantly improve the signal-to-noise ratio (from 10dB to approximately 50dB). The generated Level 4 data products have standardized formats, accurate parameters, and controllable quality. Furthermore, data from different stations and time periods exhibit good interoperability and comparability. This fully demonstrates that the invention can solve the core pain points of traditional technologies, providing stable, reliable, and standardized data support for large-scale spatiotemporal evolution research of the ionosphere, space weather early warning, and radio communication assurance, possessing strong engineering practicality and scientific research value.

[0045] Example 3: Based on the same inventive concept, this invention also provides a VHF coherent scattering radar data product generation system, the structural composition of which is shown in the schematic diagram below. Figure 5 As shown, it includes: The signal acquisition module is used to acquire ionospheric echo signals through a very high frequency coherent scattering radar. The standardization processing module is used to sequentially perform multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherence accumulation, autocorrelation analysis and power spectrum calculation and parameter extraction on the echo signal to obtain standardized processed data. The data processing module is used to generate a four-level hierarchical data product based on the standardized processed data, which sequentially corresponds to the original data, processed data, application parameters, and visualization products. The quality control module is used to perform full-process quality control on the Level 4 data products to obtain Level 4 data products that have undergone quality control. The product output module is used to standardize and annotate the quality-controlled Level 4 data products using a unified spatiotemporal reference, and output standardized VHF coherent scattering radar data products. The four-level hierarchical data products include raw echo information, spectral feature information, core application parameters, and intuitive visualization results.

[0046] For example, the very high frequency coherent scattering radar can be adapted to preset hardware parameters and deployed with an antenna array to collect backscattered echo signals from inhomogeneities in the E and F regions of the ionosphere. The preset hardware parameters may include one or more of the following: operating frequency, transmit power, pulse parameters, beamwidth, and detection range configuration; The pulse parameters may include one or more of the following: pulse width, duty cycle, and pulse repetition frequency; The antenna array can be an array structure composed of multiple rows and multiple groups of three-element Yagi antennas.

[0047] In one implementation, the standardization processing module may include: an interference suppression submodule, specifically including: A fixed interference filtering unit is used to filter out fixed interference signals outside the operating frequency band of the VHF coherent scattering radar by bandpass filtering; The random interference filtering unit is used to suppress random interference signals in the echo signal after multi-channel signal synthesis through adaptive filtering.

[0048] In one implementation, the standardization processing module may include: a digital filtering submodule, specifically including: The high-speed sampling unit is used to perform high-speed IQ sampling on the signal after radio frequency interference suppression to obtain in-phase I signals and quadrature Q signals; The downsampling unit is used to downsample the sampled signal using a preset decimation factor, and combined with matched filtering and amplitude and phase weighting, outputs a single-channel IQ echo signal.

[0049] In one implementation, the standardization processing module may include: a coherent accumulation submodule, specifically including: The mode acquisition unit is used to acquire the operating mode of the VHF coherent scattering radar. The first accumulation unit is used to perform coherent accumulation using a first preset number of pulses when the operating mode is in the E-zone mode. The second accumulation unit is used to perform coherent accumulation using a second preset number of pulses when the operating mode is in the F-zone mode. The third accumulation unit is used to perform coherent accumulation using a third preset number of pulses when the operating mode is in scanning mode. The coherent accumulation can be achieved by arithmetic summation to superimpose signal energy.

[0050] In one implementation, the standardization processing module may include: a parameter extraction submodule, specifically including: The signal partitioning unit is used to partition the coherently accumulated signal according to a preset distance gate partitioning rule and calculate the autocorrelation function of the signal within each distance gate; the time delay range of the autocorrelation function is adapted to the pulse width. The function transformation unit is used to perform a discrete Fourier transform on the autocorrelation function to obtain the power spectrum; The signal fitting unit is used to fit the power spectrum with a Gaussian function and extract core application parameters. The core application parameters may include one or more of the following: echo intensity, signal-to-noise ratio, spectral width, and Doppler velocity.

[0051] In one implementation, the quality control module may include: The error correction submodule is used to perform error correction on the Level 4 data product to obtain the Level 4 data product after error correction. The file verification submodule is used to perform file verification on the error-corrected Level 4 data product to obtain the file-verified Level 4 data product. The anomaly identification submodule is used to identify anomalies in the Level 4 data products after file verification, mark numerical anomalies that exceed the preset parameter value range, and obtain Level 4 data products that have passed quality control. The error correction includes: hardware sampling error correction and spectrum leakage error correction; The hardware sampling error correction includes: AD sampling nonlinearity correction and antenna phase deviation correction; The file verification includes: filename format verification, file header information verification, file size verification, and data point count verification.

[0052] For example, the unified spatiotemporal reference may include: a time reference, a spatial reference, and a velocity reference; The time base can be in Coordinated Universal Time (UTC) format, used to mark the time of product file names and file content; The spatial reference can be marked with the latitude and longitude of the station using the geographic coordinate system GEO, or with the elevation using the geodetic surveying system WGS84; The velocity reference can be a Doppler velocity marked with the direction away from the VHF coherent scattering radar as the positive direction.

[0053] Example 4: like Figure 6 As shown, the present invention also provides an electronic device, which may be a computer device, a microcontroller device, a smart mobile device, etc. The electronic device in this embodiment may include a processor, a memory, a transceiver component, etc. The memory, processor, and transceiver component are connected via a bus; the memory can be used to store executable programs, and an exemplary executable program may include instructions; the processor is used to execute the instructions stored in the memory. The memory can also be used to store data, which can be accessed and / or modified when instructions are executed.

[0054] The processor may be a Central Processing Unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and it is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions in the storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of the VHF coherent scattering radar data product generation method in the above embodiments.

[0055] Example 5: Based on the same inventive concept, this invention also provides a readable storage medium, specifically an electronic device readable storage medium (Memory). This readable storage medium is a memory device within an electronic device used to store programs and data. It is understood that the storage medium here can include both built-in storage media within the electronic device and extended storage media supported by the electronic device. The storage medium provides storage space, which stores the terminal's operating system. Furthermore, this storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more executable programs (including program code). It should be noted that the storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. Loading and executing one or more instructions stored in the storage medium by the processor can implement the steps of a VHF coherent scattering radar data product generation method in the above embodiments.

[0056] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0057] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0058] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0059] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit its scope of protection. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading the present invention, they can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the application, but these changes, modifications or equivalent substitutions are all within the scope of protection of the claims pending approval.

Claims

1. A method for generating VHF coherent scattering radar data products, characterized in that, include: Ionospheric echo signals were acquired using a very high frequency coherent scattering radar. The echo signal is sequentially subjected to multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherence accumulation, autocorrelation analysis, power spectrum calculation and parameter extraction to obtain standardized processed data. Based on the standardized processed data, a four-level hierarchical data product is generated, corresponding sequentially to the original data, processed data, application parameters, and visualization products. The four-level data products are subjected to full-process quality control to obtain quality-controlled four-level data products. The quality-controlled Level 4 data products are standardized and labeled using a unified spatiotemporal reference, and standardized VHF coherent scattering radar data products are output. The four-level hierarchical data products include raw echo information, spectral feature information, core application parameters, and intuitive visualization results.

2. The method as described in claim 1, characterized in that, The very high frequency coherent scattering radar is adapted to preset hardware parameters and deployed with an antenna array to collect backscattered echo signals of inhomogeneities in the E and F regions of the ionosphere. The preset hardware parameters include one or more of the following: operating frequency, transmission power, pulse parameters, beamwidth, and detection range configuration; The pulse parameters include one or more of the following: pulse width, duty cycle, and pulse repetition frequency; The antenna array is an array structure consisting of multiple rows and groups of three-element Yagi antennas.

3. The method as described in claim 1, characterized in that, Radio frequency interference suppression is performed on the signal synthesized from multiple channels, including: Fixed interference signals outside the operating frequency band of the VHF coherent scattering radar are filtered out by bandpass filtering; Random interference signals in the echo signal after multi-channel signal synthesis are suppressed by adaptive filtering.

4. The method as described in claim 1, characterized in that, IQ sampling and digital filtering are performed on the signal after radio frequency interference suppression, including: High-speed IQ sampling is performed on the signal after radio frequency interference suppression to obtain in-phase I signal and quadrature Q signal; The sampled signal is downsampled using a preset decimation factor, and then combined with matched filtering and amplitude-phase weighting to output a single-channel IQ echo signal.

5. The method as described in claim 4, characterized in that, Coherent accumulation of the single-channel IQ echo signal includes: Obtain the operating mode of the VHF coherent scattering radar; When the operating mode is in zone E mode, a first preset number of pulses are used for coherent accumulation; When the operating mode is in the F-zone mode, a second preset number of pulses are used for coherent accumulation; When the operating mode is in scanning mode, a third preset number of pulses are used for coherent accumulation; The coherent accumulation is achieved by superimposing signal energy through arithmetic summation.

6. The method as described in claim 1, characterized in that, Autocorrelation analysis, power spectrum calculation, and parameter extraction are performed on the coherently accumulated signal, including: The coherently accumulated signal is partitioned according to a preset distance gate partitioning rule, and the autocorrelation function of the signal within each distance gate is calculated; the time delay range of the autocorrelation function is adapted to the pulse width. The power spectrum is obtained by performing a discrete Fourier transform on the autocorrelation function. The power spectrum was fitted using a Gaussian function to extract core application parameters. The core application parameters include one or more of the following: echo intensity, signal-to-noise ratio, spectral width, and Doppler velocity.

7. The method as described in claim 1, characterized in that, The process of performing full-process quality control on the Level 4 data products to obtain quality-controlled Level 4 data products includes: The error-corrected Level 4 data product is obtained by performing error correction on the Level 4 data product. The error-corrected Level 4 data product is then subjected to file verification to obtain a file-verified Level 4 data product. Anomaly identification is performed on the Level 4 data product after file verification, and numerical anomalies that exceed the preset parameter value range are marked to obtain a Level 4 data product that has passed quality control. The error correction includes: hardware sampling error correction and spectrum leakage error correction; The hardware sampling error correction includes: AD sampling nonlinearity correction and antenna phase deviation correction; The file verification includes: filename format verification, file header information verification, file size verification, and data point count verification.

8. The method as described in claim 1, characterized in that, The unified spatiotemporal reference includes: a time reference, a spatial reference, and a velocity reference; The time base adopts Coordinated Universal Time (UTC) format and is used to mark the time of product file names and file contents; The spatial reference uses the geographic coordinate system GEO to mark the latitude and longitude of the stations and the geodetic system WGS84 to mark the altitude. The velocity reference is the Doppler velocity, marked with the direction away from the VHF coherent scattering radar as the positive direction.

9. A VHF coherent scattering radar data product generation system, characterized in that, include: The signal acquisition module is used to acquire ionospheric echo signals through a very high frequency coherent scattering radar. The standardization processing module is used to sequentially perform multi-channel signal synthesis, radio frequency interference suppression, IQ sampling and digital filtering, coherence accumulation, autocorrelation analysis and power spectrum calculation and parameter extraction on the echo signal to obtain standardized processed data. The data processing module is used to generate a four-level hierarchical data product based on the standardized processed data, which sequentially corresponds to the original data, processed data, application parameters, and visualization products. The quality control module is used to perform full-process quality control on the Level 4 data products to obtain Level 4 data products that have undergone quality control. The product output module is used to standardize and annotate the quality-controlled Level 4 data products using a unified spatiotemporal reference, and output standardized VHF coherent scattering radar data products. The four-level hierarchical data products include raw echo information, spectral feature information, core application parameters, and intuitive visualization results.

10. The system as described in claim 9, characterized in that, The very high frequency coherent scattering radar is adapted to preset hardware parameters and deployed with an antenna array to collect backscattered echo signals of inhomogeneities in the E and F regions of the ionosphere. The preset hardware parameters include one or more of the following: operating frequency, transmission power, pulse parameters, beamwidth, and detection range configuration; The pulse parameters include one or more of the following: pulse width, duty cycle, and pulse repetition frequency; The antenna array is an array structure consisting of multiple rows and groups of three-element Yagi antennas.

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