Carrier frequency offset estimation for OFDM systems

Orthogonal Frequency Division Multiplexing (OFDM) is broadly considered as an effective approach for future high-speed wireless multimedia communications. But it is very sensitive to carrier frequency offset between the transmitter and the receiver local oscillators, which causes intercarrier interference (10). Thus, in OFDM communication systems, carrier frequency offset must be estimated and compensated at the receiver to minimize the effects of intercarrier interference and maintain orthogonality. In this paper, The mathematic model of OFDM systems with cyclic prefix (CP) and virtual subcarrier is derived first. For the ESPRIT-like estimator, we propose a carrier frequency offset estimation algorithm using DOA-MATRIX method. After the rough estimation, it can acquire the frequency offset and matrix including channel information simultaneously, which are favorable for offset compensation and demodulation of received signals. Numerical simulations can illustrate performance of this algorithm.