Distributed Linear Convolutional Space-Time Coding for Two-Hop Full-Duplex Relay 2 × 2 × 2 Cooperative Communication Networks

In this paper, distributed linear convolutional space-time coding (DLC-STC) for two relay full-duplex (FD) $2\times 2\times 2$ cooperative communication networks is presented. A network topology model which consists of two sources, two destinations and one layer of two relays, is considered. In this communication model, two sources may transmit signals to two different destinations with the help of two relays simultaneously, which will cause inter-user interference. As a result, one has to deal with the inter-user interference in addition to the self-loop interference at the relays. Most part of the self-loop interference can be cancelled largely with the self-loop interference techniques at the relays, but the residual part is still a problem that requires proper processing. We consider that the two relays work in FD mode with an amplify-and-forward (AF) protocol, and the relay self-loop interference may not be cancelled completely from the received signals. Distributed space-time coding for this model is studied, for which the residual part of relay self-loop signal is applied to serve as a self-coding signal. With the self-coding property of the AF FD system, a distributed linear convolutional space time code is formed. Simulation experiments are conducted to evaluate the proposed DLC-STC for the considered FD relay communication network model, and the results illustrate the effectiveness of the presented approach.