Carrier Frequency Offset Estimation Using Improved Unitary Minimum Output Variance Approaches for Interleaved OFDMA Uplink Systems

This letter deals with the residual carrier frequency offset estimation based on minimum output variance (MOV) criterion without devoting training sequence and pilot symbol for uplink interleaved orthogonal frequency division multiple access systems. It has been shown that the performance of MOV estimator is degraded because the effect of noise. In conjunction with unitary transformation and subspace projection techniques, we present an improved unitary MOV (U-SIMOV) estimator to achieve the high accuracy estimate and low complexity for the noisy case. Computer simulations are provided for illustrating the effectiveness of the proposed approaches.