Novel frequency offset estimation algorithms for OFDM systems with high performance

Frequency offset estimation is the critical part in orthogonal frequency division multiplexing (OFDM) systems. A novel frequency offset estimation algorithm with high performance is proposed in the paper where the received signal is correlated with the local training sequences to eliminate the influence of training sequence firstly and then the coarse frequency offset is realized by short sequence. Once coarse frequency offset compensated, the fine estimation is achieved by delay correlating the compensated data or by using cyclic prefix. In this paper, performance of the new method is analyzed theoretically and the lower bound of the estimation is also presented. The new method has better estimation accuracy and larger estimation span. Furthermore, it gives the flexibility in the training sequence design to acquire the best timing performance or channel estimation etc.