A high-speed target stepping detection method and system based on dual channels

Abstract

The present invention provides a high-speed target step detection method and system based on dual channels, and relates to the technical field of target passive detection. The method is specifically as follows: S1: performing target search on the current radio frequency signal search area in the dual channels according to the task parameters, and obtaining two target signals; S2: performing target detection on the two target signals according to the correlation of the dual channels, and judging whether a valid target signal is detected according to the detection result, if so, going to step S3, if not, going to step S1, and performing target search on the next radio frequency signal search area; S3: obtaining target data of a corresponding satellite ground station according to the valid target signal, and substituting the target data of the corresponding satellite ground station into a satellite-ground joint positioning equation for calculation, and calculating to obtain target position information of the valid target signal, which can improve the detection accuracy of the satellite-ground joint positioning.

Description

Technical Field

[0001] The present invention relates to the technical field of target passive detection, and in particular to a high-speed target stepping detection method and system based on dual channels. Background Art

[0002] In the process of passive target detection, commonly used technical means include single-station multi-point intersection positioning, multi-station passive positioning and multi-satellite positioning. However, the above three technical means each have their own defects, as follows:

[0003] Single-station multi-point intersection positioning requires the detection equipment to be loaded onto a mobile carrier. Common mobile carriers, such as airborne platforms, vehicle-mounted platforms, ship-mounted platforms, and satellite-mounted platforms, have high requirements for the environmental adaptability of target detection equipment. There are many restrictions on the size, weight, power consumption, and antenna accuracy of the detection equipment. There are requirements for azimuth and elevation two-dimensional direction finding for the antenna, and the R&D cost is high.

[0004] Multi-station passive positioning requires multiple ground stations to work together, and has high requirements for the antenna frequency band, beam coverage, common view area and detection distance. At the same time, multiple stations that meet the conditions may not be able to cover the flight area of ​​high-speed targets. Traditional multi-station passive positioning needs to solve the time and space synchronization problems between multiple receiving stations, the weak signal detection problem of target echoes, and the high-precision positioning equation solution method. Because the signal of the measured radiation source is unknown, the multi-radiation environment pulse pairing and signal sorting problems are more complicated;

[0005] Satellite positioning has many restrictions on the satellite's transit time, satellite transponder operating frequency band and beam common view area. In addition, the construction period of satellite earth stations is very long, and the synchronization accuracy between earth station equipment is required to be high. Because the satellite covers a wide area, the search range is large and the target detection time is long. Summary of the invention

[0006] The purpose of the present invention is to provide a high-speed target step detection method and system based on dual channels. The method mainly detects target signals based on dual channels, and adopts a stepping method in a single channel to meet the automatic search for targets in the entire airspace and wide frequency band, and then detects the correlation of the two signals searched by the dual channels. When the target signal is detected, the characteristic parameters of the target signal are measured in real time, and then the satellite-ground joint positioning process is started. The single-station detection result is used as the prior information of the satellite-ground joint positioning, and the position information of the target is solved, which can improve the detection accuracy of the satellite-ground joint positioning.

[0007] In order to solve the above technical problems, the present invention adopts the following solutions:

[0008] A high-speed target stepping detection method based on dual channels, the method specifically comprises the following steps:

[0009] S0: obtaining a full spatial wide frequency band consisting of a plurality of radio frequency signal search areas, and the plurality of radio frequency signal search areas are sequentially arranged in the full spatial wide frequency band;

[0010] S1: Obtain the current RF signal search area in the full airspace wide frequency band, and perform target search in the current RF signal search area in dual channels according to the mission parameters to obtain two target signals;

[0011] S2: Target detection is performed on the two target signals according to the correlation of the two channels, and whether a valid target signal is detected is determined according to the detection result. If so, the process goes to step S3; if not, the process goes to step S1 and performs target search in the next RF signal search area;

[0012] S3: Obtain target data of the corresponding satellite ground station according to the effective target signal, and substitute the target data of the corresponding satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal.

[0013] Furthermore, in S0, the specific process of obtaining the full-space wide frequency band composed of multiple radio frequency signal search areas is as follows:

[0014] According to the receiving characteristics of the antenna, the entire preset frequency is divided into three frequency areas, each of which is used as a frequency band of a radio frequency signal search area, and two sets of antennas are used in the radio frequency signal search area to perform beam coverage within the frequency band.

[0015] Furthermore, in S2, the specific process of performing target detection on the two target signals according to the correlation of the two channels is as follows:

[0016] The baseband I / Q data of the channels corresponding to the two target signals are obtained, and the baseband I / Q data of the two channels are correlated. If the amplitude of the correlation peak is greater than the detection threshold, it is determined that a valid target signal is detected.

[0017] Furthermore, S3 specifically includes the following steps:

[0018] S31: measuring and obtaining characteristic parameters of effective target signals, and starting corresponding satellite receiving stations to collect data according to the characteristic parameters of effective target signals, so as to obtain collected data of satellite signals;

[0019] S32: preprocessing the characteristic parameters of the effective target signal and the collected data of the satellite, and aggregating the preprocessed results to form the target data of the satellite ground station;

[0020] S34: Substitute the target data of the satellite ground station into the satellite-ground joint positioning equation for calculation, and calculate the target position information of the effective target signal.

[0021] Further, the characteristic parameters of the effective target signal include the frequency, bandwidth, power, and signal-to-noise ratio of the effective target signal; in S31, the measurement process of obtaining the characteristic parameters of the effective target signal is specifically as follows:

[0022] Perform Fourier transform FFT on the effective target signal to obtain spectrum data, perform maximum retention on multiple frames of spectrum, select the frequency corresponding to the maximum spectrum amplitude as the frequency of the effective target signal; and use the power corresponding to the maximum spectrum amplitude as the power of the effective target signal; use the frequency interval within a preset range near the maximum spectrum amplitude as the bandwidth of the effective target signal; and calculate the power and noise ratio of the bandwidth within the preset range as the signal-to-noise ratio of the effective target signal.

[0023] Furthermore, in S32, the characteristic parameters of the effective target signal and the satellite collected data are preprocessed, which specifically includes the following processing: signal mixing, filtering, extraction, digital channelization and time-frequency difference parameter estimation.

[0024] Furthermore, in S31, the satellite receiving station includes a satellite receiving station for collecting primary satellite signals and a satellite receiving station for collecting neighboring satellite signals. A common viewing area is generated between the coverage range of the satellite receiving station for collecting primary satellite signals and the coverage range of the satellite receiving station for collecting neighboring satellite signals, and the common viewing area includes a coverage range of the entire airspace and a wide frequency band.

[0025] Furthermore, the target signal is an intermediate frequency signal. After the antenna receiving front end receives and low-noise-amplifies the frequency band of the RF signal search area, it is output to the frequency converter, and the RF signal is down-converted to an intermediate frequency signal through the frequency converter.

[0026] A high-speed target stepping detection system based on dual channels, comprising:

[0027] A radio frequency signal search area acquisition module: obtains a full airspace wide frequency band consisting of multiple radio frequency signal search areas, and the multiple radio frequency signal search areas are sequentially arranged in the full airspace wide frequency band;

[0028] The dual-channel target signal search module obtains the current RF signal search area in the full airspace wide frequency band, and performs target search on the current RF signal search area in the dual channels according to the mission parameters to obtain two target signals.

[0029] Target detection module: Target detection is performed on two target signals according to the correlation of the two channels, and whether a valid target signal is detected is determined based on the detection results;

[0030] Target position information positioning module: obtain the target data of the corresponding satellite ground station according to the effective target signal, and substitute the target data of the corresponding satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal.

[0031] Furthermore, the target location information positioning module also includes the following modules:

[0032] Satellite start module: measure the characteristic parameters of the effective target signal, and start the corresponding satellite receiving station to collect data according to the characteristic parameters of the effective target signal to obtain the collected data of the satellite signal;

[0033] Target data collection module: pre-processes the characteristic parameters of effective target signals and the collected data of satellite signals, and collects the pre-processed results into target data of satellite ground stations;

[0034] Satellite-ground joint positioning module: Substitute the target data of the satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal.

[0035] Beneficial effects of the present invention:

[0036] The present invention provides a high-speed target step detection method and system based on dual channels. The method mainly detects target signals based on dual channels, and adopts a stepping method in a single channel to meet the automatic search for targets in the entire airspace and wide frequency band, and then detects the correlation of the two signals searched by the dual channels. When the target signal is detected, the characteristic parameters of the target signal are measured in real time, and then the satellite-ground joint positioning process is started, and the single-station detection result is used as the prior information of the satellite-ground joint positioning, and the position information of the target is solved, so as to improve the detection accuracy of the satellite-ground joint positioning.

[0037] In addition, there is no need to move the equipment to complete single-station multi-point intersection positioning. By intercepting the target uplink communication signal and utilizing the existing satellite communication earth station, the target position can be solved by joint satellite-ground positioning. The equipment covers a wide frequency band and has strong adaptability to geosynchronous orbit satellites. It fully integrates the advantages of multi-station passive positioning and satellite positioning, saving resources and costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a flowchart of a high-speed target stepping detection method based on dual channels in Example 1 of the present invention.

[0039] Figure 2 The figure is a flowchart of automatic target search in the entire airspace and wide frequency band in Embodiment 1 of the present invention.

[0040] Figure 3This is a schematic diagram of the structural connection of the automatic target search using a wide frequency band in the entire airspace in Example 1 of the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The relative arrangement of components and steps, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

[0043] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0044] Additionally, descriptions of well-known structures, functions, and configurations may be omitted for clarity and conciseness.One of ordinary skill in the art will recognize that various changes and modifications may be made to the examples described herein without departing from the spirit and scope of the present disclosure.

[0045] Technologies, methods, and apparatus known to ordinary technicians in the relevant field may not be discussed in detail, but where appropriate, such technologies, methods, and apparatus should be considered part of the authorization specification.

[0046] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0047] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments:

[0048] Example 1

[0049] like Figure 1 As shown, a high-speed target stepping detection method based on dual channels, the method specifically comprises the following steps:

[0050] S0: obtaining a full spatial wide frequency band consisting of a plurality of radio frequency signal search areas, and the plurality of radio frequency signal search areas are sequentially arranged in the full spatial wide frequency band;

[0051] S1: Obtain the current RF signal search area in the full airspace wide frequency band, and perform target search in the current RF signal search area in dual channels according to the mission parameters to obtain two target signals;

[0052] S2: Target detection is performed on the two target signals according to the correlation of the two channels, and whether a valid target signal is detected is determined according to the detection result. If so, the process goes to step S3; if not, the process goes to step S1 and performs target search in the next RF signal search area;

[0053] S3: Obtain target data of the corresponding satellite ground station according to the effective target signal, and substitute the target data of the corresponding satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal.

[0054] Preferably, in S0, the specific process of obtaining the full spatial domain wide frequency band composed of multiple radio frequency signal search areas is:

[0055] According to the receiving characteristics of the antenna, the entire preset frequency is divided into three frequency areas, each of which is used as a frequency band of a radio frequency signal search area, and two sets of antennas are used in the radio frequency signal search area to perform beam coverage within the frequency band.

[0056] Preferably, in S2, the specific process of performing target detection on two target signals according to the correlation of the two channels is:

[0057] The baseband I / Q data of the channels corresponding to the two target signals are obtained, and the baseband I / Q data of the two channels are correlated. If the amplitude of the correlation peak is greater than the detection threshold, it is determined that a valid target signal is detected.

[0058] Preferably, S3 specifically includes the following steps:

[0059] S31: measuring and obtaining characteristic parameters of effective target signals, and starting corresponding satellite receiving stations to collect data according to the characteristic parameters of effective target signals, so as to obtain collected data of satellite signals;

[0060] S32: preprocessing the characteristic parameters of the effective target signal and the collected data of the satellite signal, and aggregating the preprocessed results to form the target data of the satellite ground station;

[0061] S34: Substitute the target data of the satellite ground station into the satellite-ground joint positioning equation for calculation, and calculate the target position information of the effective target signal.

[0062] Preferably, the characteristic parameters of the effective target signal include the frequency, bandwidth, power, and signal-to-noise ratio of the effective target signal; in S31, the measurement process of obtaining the characteristic parameters of the effective target signal is specifically as follows:

[0063] Perform Fourier transform FFT on the effective target signal to obtain spectrum data, perform maximum retention on multiple frames of spectrum, select the frequency corresponding to the maximum spectrum amplitude as the frequency of the effective target signal; and use the power corresponding to the maximum spectrum amplitude as the power of the effective target signal; use the frequency interval within a preset range near the maximum spectrum amplitude as the bandwidth of the effective target signal; and calculate the power and noise ratio of the bandwidth within the preset range as the signal-to-noise ratio of the effective target signal.

[0064] Preferably, in S32, preprocessing the characteristic parameters of the effective target signal and the satellite collected data specifically includes the following processing: signal mixing, filtering, extraction, digital channelization and time-frequency difference parameter estimation.

[0065] Preferably, in S31, the satellite receiving station includes a satellite receiving station for collecting primary satellite signals and a satellite receiving station for collecting neighboring satellite signals, and a common viewing area is generated between the coverage range of the satellite receiving station for collecting primary satellite signals and the coverage range of the satellite receiving station for collecting neighboring satellite signals, and the common viewing area includes a coverage range of the entire airspace and a wide frequency band.

[0066] Preferably, the target signal is an intermediate frequency signal. After the antenna receiving front end receives and low-noise amplifies the frequency band of the RF signal search area, it is output to the frequency converter, and the RF signal is down-converted to an intermediate frequency signal through the frequency converter.

[0067] Based on the above principles, the present invention is further described:

[0068] The present invention mainly intercepts the target uplink communication signal and uses the existing satellite communication earth station to realize the joint satellite-ground positioning and solve the target position. The equipment covers a wide frequency band and has strong adaptability to geosynchronous orbit satellites. It fully integrates the advantages of multi-station passive positioning and satellite positioning, saving resources and costs.

[0069] Specifically, in order to cover a wide frequency band, the present invention adopts an antenna receiving front end and a frequency converter. The antenna receiving front end has a two-dimensional joint scanning capability in the spatial / frequency domain, and the frequency converter has an ultra-wide frequency band coverage capability of 100MHz~50GHz. For radio frequency signals of 100MHz~50GHz, two independent channels are used to receive, convert, collect and process radio frequency signals of specified frequencies. By changing the frequency of the frequency converter, frequency domain scanning of different signals can be achieved, and by changing the direction of the antenna, spatial domain scanning of different signals can be achieved, thereby realizing frequency domain-spatial domain two-dimensional scanning of radio frequency signals in the area of ​​concern.

[0070] In this embodiment, 100MHz ~ 50GHz is selected, which is mainly suitable for portable installation platforms to achieve reception signal coverage of the 100MHz ~ 50GHz frequency band. Then, according to the reception characteristics of the antenna, the entire preset frequency is divided into three frequency regions, each of which is used as a frequency band of a radio frequency signal search area, and two sets of antennas are used in the radio frequency signal search area to perform beam coverage within the frequency band. Specifically, the three frequency regions correspond to 100MHz~2GHz, 2GHz~20GHz and 20GHz~50GHz, respectively. Each frequency band is composed of two sets of antennas, and is installed in a 45° oblique polarization manner.

[0071] When the above settings are completed, you can search for wide-band targets in the entire airspace according to the mission parameters, such as Figure 2 , Figure 3 As shown, the antenna receiving front end receives and low-noise amplifies 100MHz~50GHz, and the frequency converter down-converts the RF signal to the intermediate frequency 140MHz / 70MHz, and then realizes signal synchronous acquisition, signal preprocessing and dual-channel correlation detection of the intermediate frequency signal. Specifically, the signal detection adopts a frequency stepping method, and the frequency stepping method is adopted based on the dual channels. Then, for the dual-channel area, target detection is performed in three frequency areas of 100MHz~2GHz, 2GHz~20GHz and 20GHz~50GHz in turn. When no target is detected, it jumps from the current frequency area to the next frequency area for target detection, that is, the next frequency domain is scanned. In addition, the present invention uses an antenna to search in each frequency area, that is, in each frequency domain, the spatial domain scanning of different signals is realized by changing the direction of the antenna, then based on the stepping method, the frequency domain-spatial domain two-dimensional scanning of the RF signal in the area of ​​interest can be satisfied.

[0072] When a target is detected, the target's frequency, bandwidth, power, signal-to-noise ratio and other parameters are measured, and the intermediate frequency signal is subjected to fast Fourier transform (FFT) to obtain spectrum data. The multi-frame spectrum is held at maximum. Then, the frequency corresponding to the maximum spectrum amplitude is selected as the target frequency; the power corresponding to the maximum spectrum amplitude is selected as the target power; the frequency interval within the -3dB range near the maximum spectrum amplitude is the target signal bandwidth; the power and noise ratio of the 3dB bandwidth is calculated as the signal-to-noise ratio;

[0073] Then, after the target parameters are measured, the satellite-ground joint positioning process is started, which refers to using the existing two satellites and two ground stations, and the satellite's beam range covers the activity area and target working frequency band of the mobile target, to prepare for the satellite-ground joint positioning; collecting the collected data of the established system or other positioning system, mainly collecting the target data of the two satellites (primary satellite and neighboring satellite) and the target data of the portable high-speed target detection equipment, and collecting the target data of the two satellites (primary satellite and neighboring satellite) mainly refers to collecting the baseband I / Q target data of the satellites (primary satellite and neighboring satellite). Specifically, in this embodiment, it is represented by performing signal preprocessing on the characteristic parameters of the effective target signal and the collected data of the satellite signal, and collecting the preprocessed results to collect the target data of the satellite ground station, and the signal preprocessing includes signal mixing, filtering, extraction, digital channelization and time-frequency difference parameter estimation;

[0074] Then, by solving the satellite-ground joint positioning equation, which refers to the solution of three nonlinear equations with three unknowns, the solution result (x, y, z) corresponds to the location information of the high-speed target radiation source. In addition, when the high-speed target position result is correct, the detection process ends, otherwise it returns to the next frequency band and airspace search.

[0075] Among them, in the present invention, target detection is performed on two target signals according to the correlation of the two channels, that is, the target signal is collected through the dual-channel correlation detection, so as to calculate the position information of the target signal.

[0076] For the dual-channel correlation detection method, it is assumed that the signal emitted by the target is: ,in, is the target amplitude, is the frequency of the signal, j is the complex factor, and t is the time;

[0077] If the radiation source moves relative to the receiving station, the mathematical expression of the signal received by the two antennas is:

[0078] ;

[0079] in, is the target 1 signal received by the antenna, For target 1 amplitude, Delay the target 1 signal; is the target 2 signal received by the antenna, For target 2 amplitude, Delay the target 2 signal.

[0080] In addition, the DTO / DFO estimation expression based on the second-order statistics usually uses the complex ambiguity function (CAF) of the two signals to complete the signal correlation calculation, which is expressed as follows:

[0081] ,

[0082] Where T is the integration period, is the cross-correlation function of the input signal x and the input signal y, is the time delay, f is the frequency, is the received target signal 1, is the noise added to the target signal 1, is the received target signal 2, is the noise added to the target signal 2. is the mutual ambiguity function of target signal 1 and target signal 2, is the mutual ambiguity function of the noise added to target signal 1 and the noise added to target signal 2, is the mutual ambiguity function of target signal 1 and the noise added to target signal 2, is the mutual ambiguity function of the noise added to target signal 1 and target signal 2, is the final result of the mutual fuzzy function, is the time delay corresponding to the maximum value of the correlation peak of the cross-ambiguity function, is the frequency corresponding to the maximum value of the correlation peak of the mutual ambiguity function.

[0083] From the definition of the fuzzy function, it can be seen that it can completely suppress the influence of independent noise. In fact, it is a time-frequency representation based on the generalized cross-correlation of the signal. Each dimension operation can be regarded as a correlation operation. Therefore, the correlation of the signal directly affects the calculation result of the cross-fuzzy function. and When the mutual fuzzy function reaches the maximum value, the parameter estimation is realized, that is: ,in, is the estimated time delay corresponding to the maximum value of the cross-ambiguity function correlation peak, is the frequency estimate corresponding to the maximum value of the cross-ambiguity function correlation peak.

[0084] It can be seen from the mutual ambiguity function that since the two target signals are correlated, and the correlation between this signal and the noise and other signals is very weak, as long as the accumulation time T is long enough, the peak value of the mutual ambiguity function of this signal will be much larger than the peak value of clutter and noise.

[0085] Based on the principle of the above-mentioned dual-channel correlation detection method, specifically, when performing target detection, the downconverter carrier of channel 1 is set to F0, and the downconverter carrier of channel 2 is set to F0+10KHz. The baseband I / Q data of the two channels are calculated through the mutual ambiguity function, and it is obtained that there is a correlation between the target signal of channel 1 and the target signal of channel 2, completing the in-phase superposition and improving the signal-to-noise ratio. The amplitude of the correlation peak is greater than or equal to 20dB, that is, it is determined that the target signal is detected. Because the distance between the two receiving antennas is very close, the time delay of the high-speed target relative to the two antennas is negligible, and the downconverter carrier frequency has a frequency deviation of 10KHz when setting, so the correlation peak is in the three-dimensional result diagram of time difference-frequency difference-amplitude, the time difference parameter estimation result, the frequency difference parameter estimation result ;

[0086] Then, when a valid high-speed target is detected, the satellite-ground joint positioning process is started. The satellite-ground joint positioning selects the 172° satellite as the main satellite and 53°E as the neighboring satellite, and selects a portable high-speed target detection device as an uplink signal receiving station. Specifically, in this embodiment, the portable high-speed target detection device is mainly composed of an antenna receiving front end, a frequency converter, and a portable acquisition and processing device. The antenna receiving front end has a two-dimensional joint scanning capability in the air / frequency domain; the frequency converter has an ultra-wide frequency band coverage capability of 100MHz~50GHz, and the frequency converter can realize step-by-step frequency selection through a selection switch; the acquisition and processing device has the functions of multi-channel intermediate frequency signal acquisition and processing, and has the functions of loading a special algorithm dynamic library and application software; at the same time, the equipment is easy to disassemble and install, convenient to transport and carry, and suitable for outdoor operation.

[0087] Specifically, when the 172° and 53° two-star combination is selected, combined with a portable high-speed target detection equipment receiving station, the positioning error in most areas can be controlled within 5km.

[0088] In summary, the dual-channel correlation detection method of the present invention utilizes the correlation of target signals and can detect weak target signals. Compared with the traditional time domain detection method and frequency domain detection method, the detection performance is greatly improved. The prior information of target detection and measurement results is used to guide the joint satellite-ground positioning, thereby improving the timeliness of target positioning.

[0089] In addition, a three-choice step selection is performed for the dual channels, which can satisfy the automatic search for targets in the entire airspace and wide frequency band. By dividing 100MHz~50GHz into three frequency bands, the corresponding antenna can realize signal reception, acquisition and processing. An independent local oscillator is used in the frequency converter to make the paths between each frequency band completely independent of each other. Reasonable planning divides the equipment into three independent parts: antenna receiving front end, frequency converter, and portable acquisition and processing equipment. This ensures fault isolation in the signal reception, frequency conversion, and acquisition and processing parts.

[0090] Example 2

[0091] A high-speed target stepping detection system based on dual channels, comprising:

[0092] A radio frequency signal search area acquisition module: obtains a full airspace wide frequency band consisting of multiple radio frequency signal search areas, and the multiple radio frequency signal search areas are sequentially arranged in the full airspace wide frequency band;

[0093] The dual-channel target signal search module obtains the current RF signal search area in the full airspace wide frequency band, and performs target search on the current RF signal search area in the dual channels according to the mission parameters to obtain two target signals.

[0094] Target detection module: Target detection is performed on two target signals according to the correlation of the two channels, and whether a valid target signal is detected is determined based on the detection results;

[0095] Target position information positioning module: obtain the target data of the corresponding satellite ground station according to the effective target signal, and substitute the target data of the corresponding satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal.

[0096] Preferably, the target location information positioning module also includes the following modules:

[0097] Satellite start module: measure the characteristic parameters of the effective target signal, and start the corresponding satellite receiving station to collect data according to the characteristic parameters of the effective target signal to obtain the collected data of the satellite signal;

[0098] Target data collection module: pre-processes the characteristic parameters of effective target signals and the collected data of satellite signals, and collects the pre-processed results into target data of satellite ground stations;

[0099] Satellite-ground joint positioning module: Substitute the target data of the satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal.

[0100] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. According to the technical essence of the present invention, within the spirit and principles of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.

Claims

1. A high-speed target stepping detection method based on dual channels, It is characterized in that The method specifically comprises the following steps: S0: obtaining a full spatial wide frequency band consisting of a plurality of radio frequency signal search areas, and the plurality of radio frequency signal search areas are sequentially arranged in the full spatial wide frequency band; S1: Obtain the current RF signal search area in the full airspace wide frequency band, and perform target search in the current RF signal search area in dual channels according to the mission parameters to obtain two target signals; S2: Target detection is performed on the two target signals according to the correlation of the two channels, and whether a valid target signal is detected is determined according to the detection result. If so, the process goes to step S3; if not, the process goes to step S1 and performs target search in the next RF signal search area; S3: Obtain target data of the corresponding satellite ground station according to the effective target signal, and substitute the target data of the corresponding satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal; The S3 specifically includes the following steps: S31: measuring and obtaining characteristic parameters of effective target signals, and starting corresponding satellite receiving stations to collect data according to the characteristic parameters of effective target signals, so as to obtain collected data of satellite signals; S32: preprocessing the characteristic parameters of the effective target signal and the collected data of the satellite signal, and aggregating the preprocessed results to form the target data of the satellite ground station; S34: Substitute the target data of the satellite ground station into the satellite-ground joint positioning equation for calculation, and calculate the target position information of the effective target signal.

2. According to claim 1, a high-speed target stepping detection method based on dual channels, It is characterized in that In S0, the specific process of obtaining a full-space wide frequency band consisting of multiple RF signal search areas is as follows: According to the receiving characteristics of the antenna, the entire preset frequency is divided into three frequency areas, each of which is used as a frequency band of a radio frequency signal search area, and two sets of antennas are used in the radio frequency signal search area to perform beam coverage within the frequency band.

3. According to the dual-channel high-speed target stepping detection method of claim 1, It is characterized in that In S2, the specific process of performing target detection on two target signals according to the correlation of the two channels is as follows: The baseband I / Q data of the channels corresponding to the two target signals are obtained, and the baseband I / Q data of the two channels are correlated. If the amplitude of the correlation peak is greater than the detection threshold, it is determined that a valid target signal is detected.

4. According to the dual-channel high-speed target stepping detection method of claim 1, It is characterized in that The characteristic parameters of the effective target signal include the frequency, bandwidth, power, and signal-to-noise ratio of the effective target signal. In S31, the measurement process of obtaining the characteristic parameters of the effective target signal is specifically as follows: Perform Fourier transform FFT on the effective target signal to obtain spectrum data, perform maximum retention on multiple frames of spectrum, select the frequency corresponding to the maximum spectrum amplitude as the frequency of the effective target signal; and select the power corresponding to the maximum spectrum amplitude as the power of the effective target signal; The frequency interval within a preset range near the maximum value of the spectrum amplitude is used as the bandwidth of the effective target signal; and the power and noise ratio of the bandwidth within the preset range is calculated as the signal-to-noise ratio of the effective target signal.

5. According to the dual-channel high-speed target stepping detection method of claim 1, It is characterized in that In S32, the characteristic parameters of the effective target signal and the satellite collected data are preprocessed, which specifically includes the following processing: signal mixing, filtering, extraction, digital channelization and time-frequency difference parameter estimation.

6. A high-speed target stepping detection method based on dual channels according to claim 1, It is characterized in that In S31, the satellite receiving station includes a satellite receiving station for collecting primary satellite signals and a satellite receiving station for collecting neighboring satellite signals. A common viewing area is generated between the coverage range of the satellite receiving station for collecting primary satellite signals and the coverage range of the satellite receiving station for collecting neighboring satellite signals, and the common viewing area includes a coverage range of the entire airspace and a wide frequency band.

7. A high-speed target stepping detection method based on dual channels according to claim 2, It is characterized in that The target signal is an intermediate frequency signal. After the antenna receiving front end receives and low-noise-amplifies the frequency band of the RF signal search area, it is output to the frequency converter, and the RF signal is down-converted to an intermediate frequency signal through the frequency converter.

8. A high-speed target stepping detection system based on dual channels, It is characterized in that include: A radio frequency signal search area acquisition module: obtains a full airspace wide frequency band consisting of multiple radio frequency signal search areas, and the multiple radio frequency signal search areas are sequentially arranged in the full airspace wide frequency band; The dual-channel target signal search module obtains the current RF signal search area in the full airspace wide frequency band, and performs target search on the current RF signal search area in the dual channels according to the mission parameters to obtain two target signals. Target detection module: Target detection is performed on two target signals according to the correlation of the two channels, and whether a valid target signal is detected is determined based on the detection results; Target position information positioning module: obtain the target data of the corresponding satellite ground station according to the effective target signal, and substitute the target data of the corresponding satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal; The target location information positioning module also includes the following modules: Satellite start module: measure the characteristic parameters of the effective target signal, and start the corresponding satellite receiving station to collect data according to the characteristic parameters of the effective target signal to obtain the collected data of the satellite signal; Target data collection module: pre-processes the characteristic parameters of effective target signals and the collected data of satellite signals, and collects the pre-processed results into target data of satellite ground stations; Satellite-ground joint positioning module: Substitute the target data of the satellite ground station into the satellite-ground joint positioning equation for calculation to obtain the target position information of the effective target signal.

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