Distributed Equalization And Power Allocation For Multi-Carrier Bidirectional Filter-And-Forward Relay Networks

A multicarrier bidirectional filter-and-forward (FF) relay-assisted network in the context of device-to-device communication is investigated. The network consists of two multicarrier-based user devices that can communicate through multiple relay nodes equipped with finite impulse response (FIR) filters to equalize the frequency-selective channels. We jointly design the distributed equalization weight vector and the power allocations at the users to minimize the total transmit power under two quality of service constraints measured by the received sum-rates at the users. We propose a novel semi-closed form sub-optimal solution to this non-convex joint optimization problem. Simulation results show that the proposed design, in conjunction with the FF-based relay nodes, attains substantially better performance than the existing designs associated with amplify-and-forward and multicarrier relay nodes.