Abstract:

The energy-efficiency optimization strategy is studied for the amplify forward orthogonal frequency division multiplexing (AF-OFDM) two-way relaying system with asymmetric traffic demand. Subcarrier has two working modes: one-way relaying transmission and two-way relaying transmission. Taking the system energy-efficiency as the optimization objective, a combination optimization model of joint relaying transmission mode selection, power allocation and bit loading is structured. Firstly, fix the subcarrier allocation set, decompose the original optimization problem into two suboptimization problems, optimize power allocation of the one-way relaying transmission and two-way relaying transmission. Then, the optimal subcarrier number of the two-way relaying transmission is searched by using the linear structure formed by the subcarrier pairing, and optimize the subcarrier allocation set. Simulation results show that the proposed strategy can improve the energy-efficiency of the AF-OFDM two-way relaying system with asymmetric traffic.