A Joint Timing Offset and Channel Estimation Using Fractional Fourier Transform and Cazac Sequences

摘要

This paper deals with symbol timing offset and channel estimation in OFDM (orthogonal frequencydivision multiplexing) system in fast varying channel. Symbol timing offset (STO) estimation is a major taskin OFDM. Most of existing methods for estimating STO used cyclic prefix or training sequences. In thispaper, we consider a new system for STO estimation using constant amplitude zero autocorrelation(CAZAC) sequences as pilot sequences in conjunction with fractional Fourier transform (FRFT). After STOestimation is done, timing compensation is made. Thereafter, channel is estimated to well recover theoriginal transmitted signal. This method gives good results in terms of MSE in comparison with otherknown techniques, it estimated well the channel and it is important for fast varying channel. MATLABMonte-Carlo simulations are used to evaluate the performance of the proposed estimator.