Compensation Algorithm Of The Phase Noise In SC-FDE Satellite Systems

With the continuous development of digital multimedia communication and information globalization,satellite communication is moving towards higher communication frequency area to achieve the grand goal of Gigabit connection worldwide.The frequency band of satellite communication is rising,and the system is facing more serious phase noise interference.SC-FDE system is simple and the peak to average power ratio of RF power is relatively low,which is conducive to the miniaturization of the system and to reduce the nonlinear distortion of RF power amplifier.In this paper,problems of phase noise generation,the influence of phase noise to SC-FDE,estimation and compensation of phase noise in satellite communication system are discussed:The method of generating and expressing phase noise is expounded.The adverse effects of phase noise interference on SC-FDE satellite system are analyzed,and the traditional phase noise estimation and compensation algorithm are introduced.16QAM and 64QAM are used for the constellation mapping.Phase noise model uses Wiener model and DVB-S2 model.The MMSE equalization technique is used in the SC-FDE receiver.Two self-correction phase noise compensation algorithms are proposed.The proposed two algorithms are divided into phase noise rough compensation module and phase noise fine compensation module.In the coarse compensation module,the two self-correction algorithms use the pilot point phase noise for linear interpolation,and then complete the rough compensation for the signal.In the fine compensation module,the threshold based algorithm uses the pilot phase noise value as threshold to filter the phase noise of each symbol point,and determines whether to replace the phase noise on the symbol point According to the degree of membership of phase noise,the FCM based algorithm determine whether to replace the phase noise on the symbol.Finally,the phase noise replacement method is constantly updated by the decision feedback iteration.The simulation results show that when the rough compensation module worked only,The system BER performance of the Wiener model is superior to the DVB-S2 model.After adding the fine compensation processing module,with the increase of the cycle times,the two self-correction algorithms can improve the system BER performance.The performance of the self-correction algorithm based on the threshold is better than the self-correction algorithm based on the improved FCM.