Multi-band Strategy for Cooperative Communication Networking with Unmatched Carrier Frequencies

In this paper, we consider the cooperative networking with the presence of multiple carrier frequency offsets at different relays, which is difficult to be handled. Such an imperfect networking is inevitable due to the distributed nature of the relay system and unmatched central frequencies at different relays. We propose a multi-band scheme for cooperative communications and provide theoretical analysis of the proposed cooperative networking based on the analytical upper bound of the channel orthogonality deficiency. Theoretical analysis and simulation results show that the proposed scheme achieves the full cooperative diversity and improves the system capacity, only adopting linear equalizers such as zero-forcing and minimum mean square error equalizers. Such advatange is normlly only enjoyed by a non-linear equalizers like maximum-likelihood equalizer, whose huge complexity is however usually unacceptable.