A Simple Amplify-and-Forward Relaying Scheme Based on Clipping and Forwarding for Dual-Hop Transmissions

In this paper, we propose a simple relaying protocol, namely clip-amplify-forward (CAF), for dual-hop transmissions. In the CAF relaying protocol, the received signal at the relay node is clipped firstly and then amplified with a fixed amplification gain before retransmission. Only a hard clipper and a linear amplifier are needed at the relay node, where no channel estimation is needed. Simulation results show that with a relatively small amplification gain, the CAF relaying protocol has very close performance to the AF relaying protocol while enjoying the simplicity of implementation. A simple design criterion for the amplification gain is also presented.