Performance of coarse and fine timing synchronization in OFDM receivers

The performance of OFDM receivers is very sensitive to timing synchronization errors. This paper makes an analysis of different proposed timing synchronization algorithms, their training symbol patterns and their effect on the performance of OFDM systems under severe frequency selective Rayleigh fading. We show BER and MSE performance of six popular preamble based algorithms using joint synchronization and channel estimation to make an insightful and thorough comparison. We analyze the performance with both coarse and fine timing recovery and show that BER performance with fine timing is better for every algorithm. We propose a new technique for timing synchronization that uses Constant Amplitude Zero Auto Correlation (CAZAC) sequences to acquire unit Peak to Average Power Ratio (PAPR) for the preambles. We show that the proposed technique is robust under high delay spread environments with BER and MSE performance comparable to the best case.