Research On The Influence And Suppression Of Phase Noise In CE-OFDM Satellite Communication System

Satellite communication is a way of communication whose relay nodes are satellite.With continuous development of satellite communication,communication business is developing from traditional voice and data services to the emerging multimedia broadband services,however,the data transmission rate of single carrier modulation techniques is limited and it’s difficult to meet the need of future diversified business.Moreover,the increasing tense of low-band frequency resources leads to higher frequency band.Thus,multi-carrier communication technology is getting more and more attention in satellite communication.OFDM is the most popular communication technology due to its high spectrum efficiency and strong anti-interference ability.However,inherent high PAPR hinders its application in higher frequency satellite communication.In order to solve this problem,some new multi-carrier technologies are proposed.Constant envelop OFDM is a typical novel multi-carrier technology,it can effectively solve the inherent PAPR in OFDM by combining constant envelop modulation with OFDM,however,phase noise introduced by frequency source devices is still necessary to be solved.Phase noise will increase with the increase of communication band as usual,it’s vital to solve the high phase noise in satellite communication as future satellite communication’s band shall be higher than now.In this context,this paper focus on the study of the influence and suppression of high phase noise in CE-OFDM system.This paper mainly analyzes the change of some performance indexes in CE-OFDM system caused by phase noise and two phase noise cancellation schemes are proposed in this paper.The first scheme is based on the reference signal phase noise cancellation scheme.This scheme takes advantage of the independence of different components of received signal and the characteristic of frequency domain received signal.It can directly estimate the phase noise while transmitting reference signal and use this estimated phase noise to compensate other transmitted signals.Simulation results show that this scheme can effectively eliminate the impact of phase noise on the system when phase noise changes slowly.The second scheme is based on linear interpolation.This scheme takes advantage of Bayesian decision criterion of received signal.It can eliminate the impact of phase noise by using the estimated phase noise that can get the maximum probability of accurate decision.Simulation results show that this scheme can effectively estimate and suppress the interference caused by phase noise.