Carrier Frequency Offset Estimation for OFDM Systems With Time-Varying DC Offset
Orthogonal Frequency Division Multiplexing (OFDM) systems with direct-conversion architecture suffer from both Carrier Frequency Offset (CFO) and DC Offset (DCO). In this paper, the authors study CFO estimation problem for OFDM systems with Time-Varying DCO (TV-DCO) caused by gain mode switch of low noise amplifier (LNA). Based on linear approximation of TV-DCO, a blind algorithm is proposed for CFO estimation by means of DCO compensation and power leakage minimization. Performance of the proposed algorithm is demonstrated by simulations.