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CN-122027051-A - Real-time full capture detection method for sporadic coupled signals and storage medium

CN122027051ACN 122027051 ACN122027051 ACN 122027051ACN-122027051-A

Abstract

The invention discloses a real-time full capture detection method of an occasional coupled signal and a storage medium, wherein the method comprises the following steps of carrying out time-frequency joint analysis according to an input signal, obtaining the center frequency and bandwidth of an effective carrier, judging the type of the effective carrier according to the duty ratio, amplitude fluctuation, burst frequency and periodic characteristics to form a carrier detection result, wherein the carrier detection result comprises the center frequency, bandwidth, amplitude and type of each effective carrier, carrying out carrier change detection, namely obtaining a historical carrier parameter set, comparing each effective carrier in the carrier detection result with the historical carrier parameter set, judging whether the effective carrier in the carrier detection result is newly added or unchanged, judging whether the historical carrier in the historical carrier parameter set is disappeared, storing the input signal according to the center frequency when the newly added carrier exists, and deleting corresponding storage data when the historical carrier disappears. And the carrier wave is rapidly detected and stored.

Inventors

  • ZENG ZHAOLI
  • LI JUNFU

Assignees

  • 浙江扬铭科技发展有限公司

Dates

Publication Date
20260512
Application Date
20260330

Claims (10)

  1. 1. The real-time full capture detection method for the sporadic coupled signals is characterized by comprising the following steps of: The carrier detection comprises the steps of carrying out time-frequency joint analysis according to an input signal, obtaining the center frequency and the bandwidth of an effective carrier, judging the type of the effective carrier according to the duty ratio, the amplitude fluctuation, the burst frequency and the periodic characteristic, and forming a carrier detection result, wherein the carrier detection result comprises the center frequency, the bandwidth, the amplitude and the type of the effective carrier; And detecting carrier variation, namely comparing the effective carrier in the carrier detection result with a linked list to be detected, and storing the carrier detection result into the linked list to be detected according to the comparison result.
  2. 2. The method according to claim 1, wherein in carrier detection, performing time-frequency joint analysis according to an input signal to obtain a center frequency and a bandwidth of an effective carrier comprises the steps of: Performing anti-aliasing filtering processing and windowing processing on an input signal to obtain a time domain signal; performing sliding FFT on the time domain signal and calculating corresponding power spectral density; Extracting a frequency spectrum region formed by frequency points with the power spectrum density larger than a power threshold value in the time domain signal as a candidate carrier region; combining adjacent candidate carrier wave areas with the frequency interval smaller than the frequency threshold value to form an effective carrier wave area; and calculating the center frequency by adopting a centroid method aiming at each combined effective carrier region, and obtaining the bandwidth based on the power spectrum densities of a plurality of frequency points near the peak value.
  3. 3. The method of claim 2, wherein the power spectral density is calculated by the formula: ; In the formula, In order to be a power spectral density, For the index of the frequency point, The number of calculation points for the FFT, In order to achieve a signal sampling rate, In the form of a discrete fourier transform, For the input sequence of time-domain signals, Is a sequence of window functions; The power threshold is calculated by the following formula: ; In the formula, The average absolute value deviation is used as the average absolute value deviation, As a result of the power threshold value, As a function of the median number of the functions, Is an empirical coefficient.
  4. 4. The method of detecting according to claim 2, wherein obtaining the bandwidth based on the power spectral densities of the plurality of frequency bins near the peak value comprises the steps of: selecting a frequency point corresponding to the maximum value of the power spectrum density And two adjacent frequency points on the left and right sides thereof And Respectively marked as Wherein 、 、 The power spectrum density values of the corresponding frequency points are respectively; fitting a parabolic function according to three frequency points: ; wherein a is a parabolic coefficient; the bandwidth is obtained according to the following formula: ; In the formula, Is a half-high power value, Is a parabolic coefficient.
  5. 5. The method of claim 2 or 4, wherein the frequency threshold is 50Hz.
  6. 6. The method according to claim 1, wherein in carrier detection, determining the type of the effective carrier according to the duty ratio, the amplitude fluctuation, the burst number, and the periodicity characteristics comprises the steps of: When the duty ratio is more than 80% and the amplitude fluctuation is less than 5%, judging that the effective carrier is a continuous carrier; when the duty ratio is less than 30% and the burst frequency is less than 5 times/min, judging that the effective carrier is a burst carrier; when the duty ratio is 30% -70%, and the autocorrelation function has a significant peak value at the time slot period, calculating the time slot period corresponding to the peak value When the slot cycle is 10 consecutive cycles Fluctuation is less than 5%, and the TDMA carrier is judged.
  7. 7. The method according to claim 1, wherein in carrier change detection, comparing the effective carrier in the carrier detection result with the linked list to be detected, and storing the carrier detection result into the linked list to be detected according to the comparison result comprises the steps of: the chain table to be detected comprises a plurality of history carriers which are arranged in ascending order according to the center frequency; Initializing the index value of a linked list to be detected to be 1; Reading an effective carrier in the carrier detection result as a carrier which needs to be detected to change currently; reading the linked list data to be detected corresponding to the current index value, and comparing the linked list data to be detected with the center frequency, the signal bandwidth and the signal amplitude of the carrier wave of which the change is required to be detected currently; if the center frequency of the carrier wave to be detected is larger than the center frequency of the linked list to be detected, adding 1 to the index value of the linked list to be detected; If the center frequency of the carrier wave to be detected is smaller than the center frequency of the linked list to be detected, inserting a new linked list element before the current index value of the linked list to be detected, storing the data of the carrier wave to be detected into the new element, judging that the carrier wave is a new carrier wave, and adding 1 to the index value of the linked list to be detected; If the center frequency of the carrier wave to be detected and changed currently is equal to the center frequency of the linked list data to be detected and the signal bandwidth is equal to the signal bandwidth of the linked list data to be detected, judging that the carrier wave is unchanged, updating the data of the carrier wave to be detected and changed currently to the linked list to be detected of the current index, and then adding 1 to the index value of the linked list; if the center frequency of the carrier wave to be detected and changed currently is equal to the center frequency of the linked list data to be detected, but the signal bandwidth is not equal to the signal bandwidth of the linked list data to be detected, judging that the carrier wave is subjected to parameter change, updating the data of the carrier wave to be detected and changed currently to a historical carrier wave linked list element of a current index, and then adding 1 to the index value of the linked list; And repeatedly executing the steps until the comparison of the effective carriers of the carrier detection results is completed.
  8. 8. The method of detecting according to claim 7, further comprising the steps of: judging whether the maximum value of the index of the chain table to be detected is larger than the current index value, if so, deleting the chain table data after the current chain table index value, and enabling the maximum value of the chain table index to be equal to the current chain table index value.
  9. 9. The method according to claim 1, further comprising the step of, in carrier change detection: Storage is handled by DDC.
  10. 10. A storage medium storing a computer program, wherein the computer program when executed by a processor performs the steps of a method for real-time full capture detection of sporadic coupled signals according to any one of claims 1 to 9.

Description

Real-time full capture detection method for sporadic coupled signals and storage medium Technical Field The application relates to the field of space-based signal detection, in particular to a real-time full-capture detection method for sporadic coupled signals and a storage medium. Background Under the space-based reconnaissance scene, the geosynchronous orbit station can realize continuous monitoring of a specific area, and the unsynchronized orbit station has wide area coverage and maneuver reconnaissance capability, and the complexity of sporadic signal detection is further increased due to the differences of different platforms in the aspects of observation view angle, signal receiving gain, dynamic range and the like. Coupling signals are a type of communication format used by a particular user. Such users often belong to high value targets that require significant attention. The communication behavior of such users is characterized by bursts, short periods, irregular patterns, etc., for example, the coupling duration is only 500ms within 1 hour. Particularly, when the input signal is 950 MHz-2150 MHz, how to realize reliable detection and capture of the coupling signal in the 1.2GHz bandwidth is a key technical challenge for improving important target reconnaissance. To ensure that the coupled signal can be reliably detected and captured, real-time processing is required, i.e., detection and capture of any short burst signal cannot be missed. The sporadic signal is usually not hard-wired to the time at which the result is detected, i.e. the processing delay. Nevertheless, it is still necessary to perform signal detection and processing within an effective time by technical means. In order to avoid signal missing, the traditional signal detection method is often complex in algorithm, has long processing time and is difficult to process in real time, or has the problem that the algorithm simply meets the real-time processing requirement but the signal missing detection exists, and the requirements on coupled signal detection cannot be met. Disclosure of Invention In view of the above problems, the application provides a real-time full capture detection method and a storage medium for an occasional coupled signal, which solve the problems of incomplete capture or long time of the conventional occasional coupled signal. In order to achieve the above purpose, the present inventors provide a real-time full capture detection method for sporadic coupled signals, comprising the following steps: The carrier detection comprises the steps of carrying out time-frequency joint analysis according to an input signal, obtaining the center frequency and the bandwidth of an effective carrier, judging the type of the effective carrier according to the duty ratio, the amplitude fluctuation, the burst frequency and the periodic characteristic, and forming a carrier detection result, wherein the carrier detection result comprises the center frequency, the bandwidth, the amplitude and the type of the effective carrier; And detecting carrier variation, namely comparing the effective carrier in the carrier detection result with a linked list to be detected, and storing the carrier detection result into the linked list to be detected according to the comparison result. Further, in carrier detection, performing time-frequency joint analysis according to an input signal to obtain a center frequency and a bandwidth of an effective carrier includes the following steps: Performing anti-aliasing filtering processing and windowing processing on an input signal to obtain a time domain signal; performing sliding FFT on the time domain signal and calculating corresponding power spectral density; Extracting a frequency spectrum region formed by frequency points with the power spectrum density larger than a power threshold value in the time domain signal as a candidate carrier region; combining adjacent candidate carrier wave areas with the frequency interval smaller than the frequency threshold value to form an effective carrier wave area; and calculating the center frequency by adopting a centroid method aiming at each combined effective carrier region, and obtaining the bandwidth based on the power spectrum densities of a plurality of frequency points near the peak value. Further, the power spectral density is calculated by the following formula: ; In the formula, In order to be a power spectral density,For the index of the frequency point,The number of calculation points for the FFT,In order to achieve a signal sampling rate,In the form of a discrete fourier transform,For the input sequence of time-domain signals,Is a sequence of window functions; The power threshold is calculated by the following formula: ; In the formula, The average absolute value deviation is used as the average absolute value deviation,As a result of the power threshold value,As a function of the median number of the functions,Is an empirical coefficient. Further