Channel coding for the relay channel

Abstract

The relay channel consists of an input, a relay, and a destination. The source transmits x11. A relay, which receives that as y2, will decode it and transmit x2 as a function of x11. Finally, the destination receives x11, x12, and x2 as y3, which it decodes. If done correctly, x12 and x2 will sum coherently and the resulting y3 will be superior to simply sending the message straight from source to destination at 2x the power. In this thesis, two cases are considered. The cases are full duplex relaying and half duplex relaying. Full duplex relaying is where the relay can send and receive at the same time. This is implemented using backward decoding, a form of superposition block Markov encoding, as well as QPSK signaling. The half duplex case is where the relay cannot send and receive on the same channel at the same time. This is implemented using TDD. Code shortening is used to achieve the relaying objective.