Power Allocation Strategies across N Orthogonal Channels at Both Source and Relay

TL;DR

This paper investigates optimal power allocation strategies in a relay network with N orthogonal channels, aiming to maximize capacity under power constraints, considering different information availability scenarios.

Contribution

It formulates and solves various optimization problems for power allocation at source and relay, providing insights into optimal strategies under different channel information conditions.

Findings

Optimal power allocation strategies are derived for different information scenarios.

Properties of the optimal solutions are theoretically analyzed.

The strategies improve capacity under limited power constraints.

Abstract

We consider a wireless relay network with one source, one relay and one destination, where communications between nodes are preformed via N orthogonal channels. This, for example, is the case when orthogonal frequency division multiplexing is employed for data communications. Since the power available at the source and relay is limited, we study optimal power allocation strategies at the source and relay in order to maximize the overall source-destination capacity under individual power constraints at the source and/or the relay. Depending on the availability of the channel state information at the source and rely, optimal power allocation strategies are performed at both the source and relay or only at the relay. Considering different setups for the problem, various optimization problems are formulated and solved. Some properties of the optimal solution are also proved.