Research Of Automatic Recognition Of Communication Signals Modulation

Automatic recognition of communication signals modulation has a very important position in the field of communication electrical antagonizing,radio signal management, etc, and it is the required function of Software Radio Receiver. With the rapid developing of communication technology, the system and modulation manner of communication signals become more and more complicated and various. It results in that in the recent years the theory of modulation recognition has become the hot problem in the field of signal processing.Automatic recognition of modulation is the method of distilling proper feature parameters and then recognizes the modulation manner by proper sorting arithmetic.This thesis presents the history and the actuality of the modulation recognition research, and summarizes the basic theory of the modulation of communication signal. First of all, the thesis studies the method to extract featureparameters(γ_max,R,P,σ_aa,μ₄₂^a,N1,N2,N4 ) from time domain and frequency domain, and identifies the familiar communication signal ( AM, DSB, SSE, 2ASK, 4ASK, 2FSK, 4FSK, BPSK, QPSK, 16QAM ) by wavelet transform. It researches how to ascertain the feature parameters thresholding in the theory. And it demonstrates the practicability of the method by simulation data and actual sampling data.Secondly, the thesis explores to constitute the feature parameters (f_x1,f_x2, f_x3, f_x4 ) through the high order accumulated amount, and identifies the digital communication signal by wavelet transform. In the presupposition of the awareness of precise carrier frequency, this method can classify the 6 signals 4ASK, 2FSK,...