Noise frequency modulation signal identification method

Abstract

The invention provides a noise frequency modulation signal identification method, and belongs to the technical field of communication. According to the method, the intrinsic characteristics of noise frequency modulation are extracted and judged by utilizing the characteristics of the noise frequency modulation in frequency spectrum and energy distribution, so that the purpose of accurately identifying the noise frequency modulation signal is achieved. Specifically, digital MPSK modulation signal judgment, digital MASK modulation signal judgment, digital MFSK modulation signal judgment and analog modulation judgment are sequentially carried out, and the residual frequency hopping signals are recursively sorted by utilizing the exclusiveness of two frequency hopping signals in the same period. Features are extracted through a signal time domain and a signal frequency domain, parameter estimation is carried out by means of spectral lines and frequency spectrums, noise frequency modulationsignal recognition is carried out according to a priority step-by-step confirmation method, and the method has the advantages of being simple in algorithm, small in calculated amount, easy in featureextraction and low in engineering implementation difficulty.

Description

technical field [0001] The invention belongs to the technical field of communication, in particular to a noise frequency modulation signal identification method. Background technique [0002] Noise frequency modulation technology has been applied in the field of electronic countermeasures as a means of covering communication interference. Its main principle is to use random noise to generate frequency modulation signals, which are used to flood and cover useful signals, so as to achieve the purpose of interfering with communication. [0003] At present, there have been many studies on the classification and recognition of conventional digital modulation signals, but there is still a certain gap in the method of distinguishing interference signals. For noise FM signals, due to the strong randomness of the signal, large coverage and relatively flat power, commonly used digital signal feature extraction techniques, such as instantaneous correlation estimation, rate estimation,...

AI Technical Summary

Problems solved by technology

[0003] At present, there have been many studies on the classification and recognition of conventional digital modulation signals, but there is still a certain gap in the method of distinguishing interference signals

For noise FM signals, due to the strong randomness of the signal, large coverage and relatively flat power, common digital signal feature extraction techniques, such as instantaneous correlation estimation, rate estimation, and constellation diagram judgment, are no longer able to extract noise FM signals. Instantaneous features, its correlation cannot be calculated, and its modulation feature information is difficult to extract

In addition, because it belongs to the frequency modulation signal, it has a certain characteristic that the amplitude of the frequency modulation signal does not change, and it is easy to be confused with the non-amplitude modulation modulation signal. Therefore, relying on the conventional modulation characteristic analysis method to detect and identify the noise frequency modulation signal has certain limitations.

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