Research And Implementation Of PSK Signal Parameter Estimation Methods In Non-Cooperative Communication

Non-cooperative communication is a communication method without certificated or any knowledge of transmitter.Signal parameter estimation is an important part of non-cooperative communication system,a prerequisite for digital signal processing such as modulation recognition and demodulation.Parameter estimation is also the key technology of Cognitive Radio?CR?which needs to analyze signals in various systems and frequency bands.Therefore,for the purpose communicating with each system ever mentioned,it is necessary to estimate several signal parameters such as carrier frequency and symbol rate.This article mainly focuses on the research of carrier frequency and symbol rate estimation of PSK signal,which introduces Hilbert-Huang and wavelet transform.It proposes a carrier frequency estimation algorithm of PSK signal based on HHT and analyzes several traditional methods.After analyzed traditional methods of estimating carrier frequency,an improved algorithm of PSK signal carrier frequency estimation based on HHT has been put forward,and simulation experiments have been done to compare the performance of the kinds of algorithm.The improved algorithm purposed in this paper could work lower than-5dB at the normalized mean square error less than 10^-1 and relative error less than 5%,which performs better than other traditional methods.The estimation of symbol rate has been studied based on the PSK baseband signal which could be obtained by down conversion.The article has researched multi-scale wavelet transform method and autocorrelation method and pointed that compared with autocorrelation method the wavelet transform is of better performance for less volunteer of frequency offset.Last,the article has designed a system of PSK signal parameter estimation based on a general SDR platform,including parameter estimation algorithm,hardware structure and SCA architecture.SCA waveform component and application of parameter estimation system have been developed,code of parameter estimation which could integrate with SCA waveform container designed,a PC interface program completed.The system based on SCA has been tested and obtained the result that the relative error of carrier frequency is less than 1%and of symbol rate 0.6%,which indicates accuracy of the SCA waveform component and application and the effectiveness of the parameter estimation algorithm.