Blind carrier frequency offset estimation for OFDM systems by probability density function

Orthogonal frequency division multiplexing (OFDM) is a technique widely used for wireless communication applications. All the subcarriers are orthogonal to each other in OFDM systems. However, carrier frequency offset (CFO) may distort the orthogonality of the subcarriers and it must be estimated and compensated to maintain the system performance. A blind carrier frequency offset estimator based on the phase probability density function (pdf) is proposed in this paper. The proposed CFO estimator can operate under additive white Gaussian noise (AWGN) and multipath channels without known training signal, virtual carrier, and redundant guard interval. When compared with subspace-based blind estimators, the proposed estimator can provide better mean-squared-error performance.