Timing and Frequency Synchronization Algorithm Based on CAZAC Sequences for OFDM Systems

Symbol timing offset and carrier frequency offset will seriously deteriorate the performance of the OFDM system. Based on the CAZAC sequences which have the repetitive structure, this paper presents a synchronization algorithm for OFDM system. The proposed algorithm utilizes only one symbol to realize the synchronization of symbol timing offset, integer frequency offset and fractional frequency offset. First, the proposed algorithm completes the coarse timing synchronization and integer frequency offset estimation simultaneously. Then, we use the integer frequency offset to update the timing offset estimation. At last, we get the fractional frequency offset. The analysis and simulation results demonstrate that compared with classical synchronization algorithms, the proposed algorithm not only increases the transmission efficiency of the OFDM systems, but also significantly improves the performance of the estimation of timing offset and frequency offset. Therefore, compared with other CAZAC synchronization algorithms, the proposed algorithm enhances the adaptability to the multi-path channel.