Study On Parameters Estimation Of Psk Signal With Non-gaussian Noise

In recent years, with the development of communication environment increasingly complex, the digital signal processing methods in Gauss white noise have many shortcomings in the actual communication environment. Through the study, the noise in practical communication system often has a notable pulse characteristic, and usually modeled by Alpha stable distributionling. Because the PSK signals have strong anti-jamming ability, and can effectively broaden the bandwidth of signals, they are widely used in high speed data transmission. In addition, in the field of non-cooperation communication, effective and accurate parameter estimations of signals can provide important basis to demodulation, identification, signal recovery and other subsequent work, so it is the essential factor in signal processing. Therefore, some parameters estimation for PSK signal in Alpha stable distribution noise environment are propose in this paper. The author’s major contributions are outlined as follows:1. Aimming at that the carrier frequency estimation method for PSK signals in Alpha stable distribution noise has poor performance in the low SNR conditions, a new method based on cyclic covariance spectral is proposed in this paper to solve this problem. In the method, the cyclic covariance function is consructed, then the circulation covariation spectrum is derived, and the feature of spectrum section is extracted. According to the relationship between the section feature and the carrier frequency, the realization of the carrier frequency estimation method for PSK signals in Alpha stable distribution noise is well completed. In addition, the Cramer Rao bound(CRLB) of the estimation above is also derived and analyzed in this paper. The final simulation results show that the proposed method has a better performance in the Alpha stable distribution noise at low SNR.2. Aiming at the difficulties in estimating the symbol rate of PSK signals with Alpha stable distribution noise, a new method based on fractional order discrete-time region accumulation was proposed to solve this problem. The method did fractional order operations on both the discrete-time points and their accumulations, and construct the fractional order discrete-time region accumulation map, then there will be peak values at the. Finally, searched the minimum distance between two of the phase hopping positions to get the symbol rate. In addition, the Cramer-Rao Lower Bound(CRLB) of the symbol rate of PSK signals with Alpha stable distribution noise was theoretically analyzed and derived. Simulation results show that the proposed method not only has better performance but also has lower computation complexity in an Alpha stable distribution noise environment.