On the DMT Optimality of Time-Varying Distributed Rotation Over Slow Fading Relay Channels

摘要: We consider a slow fading two-hop relay channel where source terminal communicates with destination through layer of relays without direct link. First, we introduce the notion time-varying distributed rotation and propose linear relaying scheme called rotate-and-forward (RF). The main idea is to create convert spatial diversity time diversity. It shown that this achieves optimal diversity-multiplexing tradeoff (DMT) full-duplex relays. While more involved non-linear schemes previously proposed in literature are same setting, show here simple can also be DMT optimal. Then, extend RF multiple hops optimality two-antenna case shown. Finally, apply decode-and-forward order as previous achieved low signaling complexity.