Power Allocation in Amplify and Forward Relays with a Power Constrained Relay

TL;DR

This paper investigates optimal power allocation strategies in a two-hop MIMO relay system with power constraints, comparing Zero Forcing and MMSE receivers to improve efficiency and meet QoS requirements.

Contribution

It introduces a novel power allocation scheme at the source considering relay power constraints and analyzes its performance with different receiver types.

Findings

Zero Forcing and MMSE receivers have different performance trade-offs.

Optimal power allocation reduces source transmit power while satisfying QoS.

Simulation results demonstrate the effectiveness of the proposed scheme.

Abstract

We consider a two-hop Multiple-Input Multiple-Output channel with a source, a single Amplify and Forward relay, and the destination. We consider the problem of designing precoders at the source and the relay, and the receiver matrix at the destination. In particular, we address the problem of optimal power allocation scheme at the source which minimizes the source transmit power while satisfying a given Quality of Service requirement at the destination, and a power constraint at the relay. We consider two types of receiver at the destination, a Zero Forcing receiver and an Minimum Mean Square Error receiver. Simulation Results are provided in the end which compare the performance of both the receivers.