Joint symbol detection and channel estimation for MC-CDMA systems in the presence of carrier frequency offset

The problem of carrier frequency offset in multicarrier code-division multiple-access (MC-CDMA) systems is studied in this research. We present an iterative approach based on the expectation-maximization (EM) algorithm to estimate system parameters, including the channel state information, the carrier frequency offset and the interference-plus-noise covariance matrix. Furthermore, the symbol detection is jointly achieved through the evaluation of the Kullback-Leibler information measure required for the EM iteration. A closed form expression of the modified Fisher information matrix (MFIM) is derived to obtain the the modified Cramer-Rao bound (MCRB) of the vector version. Finally, we verity the effectiveness of the proposed algorithm with computer simulation.