Date Added: Mar 2012
The well known problem in an Orthogonal Frequency Division Multiplexing (OFDM) system is its sensitivity to frequency offset. Most of the coherent OFDM systems transmit pilot symbols on some of the subcarriers to estimate channel attenuation and also add a Cyclic Prefix (CP) to avoid inter carrier interference and inter symbol interference. An estimation algorithm based on the redundancy of both cyclic prefix and pilot subcarriers is proposed for the correction of frequency offset. If the frame timing is synchronized in advance, by considering the two kinds of redundancy simultaneously, the performance of the proposed hybrid algorithm achieves significant improvement under low SNR and short CP.