Multiple CFOs Compensation and BER Analysis for Cooperative Communication Systems

In cooperative communication systems, multiple carrier frequency offsets (MCFO) appear due to the different accuracy of the nodes' oscillators and Doppler spreads, which drastically degrades the performance of space-frequency block coded (SFBC) cooperative systems. In this paper, a MCFO compensation algorithm including modified SFBC decoder, minimum Euclidean distance decision criterion and interference reconstructing eliminator is proposed. Besides, the bit error ratio (BER) lower bound of cooperative communication systems with MCFO is theoretically derived. From the simulations, the correctness of our theoretical analysis can be validated, and it is also proved that the proposed compensation algorithm achieves good BER performance with a large range of MCFO.