Joint Estimation of Channel,Residual Carrier and Sampling Frequency Offset for OFDM Systems in Time-varying Rayleigh Channel

摘要

In this paper we establish a system model which roundly considers residual carrier frequency offset (RCFO),sampling frequency offset (SFO) and channel complex gains for orthogonal frequency-division multiplexing (OFDM) systems in a time-varying Rayleigh channel.Based on this system model,we propose a new pilot-assisted iterative algorithm for jointly estimation of RCFO,SFO and channel complex gains.In the proposed iterative algorithm,polynomial basis expansion model (P-BEM) is adopted to model the time-varying Rayleigh channel,QR-detection is employed to recover the data signal and a auto-regressive (AR) model is adopted to model the parameters to be estimated,which makes it possible to use the Extended Kalman Filtering (EKF) estimator.All of these mentioned above makes the iterative algorithm have advantages of high estimation accuracy and fast convergence speed.