Time division multiple access methods in bi-directional cooperative relay networks

In this paper, we develop a new class of time division multiple access schemes for bi-directional multiuser communications in cooperative amplify-and-forward relay networks. The proposed schemes enable a flexible trade-off between spectral efficiency and suppression of multiuser interference. The relay weights are chosen to maximize the minimum received quality-of-service of all the users under constraints on the individual and the total power at the relays. Simulation results demonstrate that the selection of the scheme has a considerable impact on the achieved throughput of the relay network.

I. INTRODUCTION

In wireless communication networks, the terminals can cooperate to increase the throughput of the network and to reduce the total transmitted energy in the network, hence, increasing the spectral efficiency of the network. In such a cooperative network, some of the terminals act as relays to establish communication links. If no direct communication is possible due to fading and shadowing effects, the relays forward the signals transmitted from one or multiple sources to their destinations [1].