Sparse-training-sequence-aided OFDM systems for CFO effect mitigation

A sparse-training-sequence-aided orthogonal frequency division multiplexing system is proposed to enable channel estimation and data detection without being affected by carrier frequency offset (CFO) effect. With the aid of the sparse training sequence, an approximate maximum likelihood estimation on CFO effect and channel response is developed to retrieve the CFO and channel response information from the received signal, and then facilitate the corresponding CFO effect compensation during channel estimation and data detection. Simulation results show that the proposed approach provides similar error performance to that with perfectly known CFO and channel response.