Joint blind timing and frequency offset estimation for MIMO-OFDM over spatially correlated fading channels

With the reduced size of mobile devices and the adoption of MIMO channels in wireless applications, the impact of spatial correlation on the design of wireless communication systems has to be investigated. In this paper, we consider the blind joint symbol timing and frequency offset estimation for MIMO-OFDM systems over spatially correlated frequency selective fading channels. Taking the spatial correlation into account, we first derive a blind joint symbol timing and frequency offset estimator by exploiting the second order cyclostationarity (CS) of received signals and using the least square estimation technique. The effect of the number of transmitters and receivers, the antenna spacing and the angle of arrivals on the performance of the proposed estimator is next investigated. It has been shown that the MSE performance of the proposed symbol timing and frequency offset estimators improves with the increase in SNR, the number of antennas, the number of OFDM symbols used for estimation, while degrades with the increase in the number of channel path and the spatial correlation which is a function of antenna spacing and angle of arrivals (departure).