A General Transmission Scheme for Bi-Directional Communication by Using Eigenmode Sharing

In this paper, we develop a general transmission scheme for bi-directional communications by using eigenmode sharing, where existing two-way relaying protocols can be viewed as a special case of the proposed transmission scheme. In addition, the proposed bi-directional scheme can also be applied to more challenging scenarios with more than one source pair. Asymptotical behavior of the outage probability achieved by the proposed transmission protocol is studied in order to obtain insightful understandings for the fundamental limits of the proposed scheme. Our developed results show that the proposed bi-directional transmission scheme can realize larger system throughput than time sharing based approaches, and serving more than one pair at the same time is more beneficial than simple two-way relaying in terms of multiplexing gains.