MMSE-Based CFO Compensation for Uplink OFDMA Systems with Conjugate Gradient
9 Abstract— Carrier Frequency Offset (CFO) compensation is very important for reliable detection of transmitted data in uplink Orthogonal Frequency Division Multiple Access (OFDMA) systems. In this paper we proposed a low-complexity CFO compensation algorithm based on the Minimum Mean Square Error (MMSE) criterion for uplink OFDMA systems. The proposed algoritm employs a Conjugate Gradient (CG) method which iteratively finds the MMSE solution. In this paper we are presenting the proposed method by comparing with the existing direct MMSE method and we show that CFO can be compensated with substantially reduced computational complexity by applying the CG method.