A Detection and Recognition Method of Direct Spread Signal

Abstract

The present invention provides a method for detection and identification of direct spread signals, the steps of which include: 1. Calculate the power spectrum of the received signal, and perform logarithmic calculation on the power spectrum; then use the logarithmic calculation result as the detection 2. Filter the detection spectrum; 3. Find the maximum value Vmax in the filtered signal, and obtain the mean value Vmean of the filtered signal; 4. The ratio of the maximum value Vmax and the mean value Vmean is used as the detection feature value E, that is, E=Vmax / Vmean; 5. The detection feature value E is compared with the set threshold ethreshold to judge: if E>ethreshold, it is judged that the received signal is a direct spread signal . This method makes full use of the periodicity of the pseudocode component in the direct sequence spread spectrum signal in the frequency domain and time domain, and uses logarithmic operations to enhance the discrete component submerged in the continuous quantity, thereby reducing the impact of noise on the recognition performance. It is simple to implement, easy to implement in engineering, and has high signal identification efficiency.

Description

technical field [0001] The invention relates to the field of communication signal processing, in particular to a method for detecting and identifying direct spread signals, which is used to distinguish conventional communication signals from direct spread signals. Background technique [0002] The detection and identification of communication signals is one of the key technologies in the field of single satellite electronic reconnaissance. The task of signal detection and identification is to determine whether there is a useful signal in the received signal, and to identify the modulation mode of the signal. The detection and recognition process may be disturbed by noise, and some modulation information needs to be known. Effective detection and identification can provide a basis for follow-up work such as demodulation, analysis, or interference. [0003] Most of the early detection and identification methods were to change the received high-frequency signal to intermediat...

AI Technical Summary

Problems solved by technology

But this kind of method also has some problems. For these methods, the conventional communication signal and the direct spread signal have similar characteristics, so although these methods can detect whether the signal exists, they cannot distinguish whether the target signal is a conventional signal or a direct spread signal. Signals, which means that methods of this class are susceptible to regular signals

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