Non-Data-Aided Sampling Frequency Synchronization  Algorithm for OFDM System

This paper studies the problem of sampling frequency synchronization for orthogonal frequency division multiplex (OFDM) systems， and proposed a low complexity Non-Data-Aided (NDA) Sampling frequency synchronization algorithm. The proposed algorithm use timedelay correlation (TDC) of received time domain OFDM signal to get the period marker which is inherit property of cyclic prefix (CP) based OFDM， then get sampling frequency offset (SFO) through comparing the received sample numbers with transmitted sample numbers in the same time. From analysis of the algorithm， we can find that the algorithm does not need do OFDM symbol synchronization and carrier estimation in advance because it works in time domain. The simulation results show that the performance of proposed algorithm is only affected by the cumulate time and cyclic prefix length， and not affected by sampling frequency offset， carrier frequency offset and the modulation type of OFDM subcarrier; and the simulation results also show the proposed algorithm has better performance in sixdelay typical urban area channel when compared with other algorithm.