A novel OFDM receiver in the flat-fading channel

Coherent orthogonal frequency division multiple access (OFDM) systems are highly sensitive to the carrier frequency offset (CFO) and the channel estimation errors. In this paper, we develop a novel scheme for joint carrier frequency offset and channel estimation in a Rayleigh flat-fading channel. Unlike existing alternatives, the proposed CFO estimators relying on second-order statistics of OFDM signals don´t require the transmission of known sequences. A simple time-domain weighted algorithm based channel estimation with pilot-data multiplexed scheme is investigated. The only necessary assumption for CFO correction is the use of different powers for different subcarrier transmitter (weighted subcarrier, WSC). The simulation results show that the proposed methods achieve more accurate estimation of the CFO and the time-variant channel parameter than the conventional schemes, and the system performance is improved dramatically