On the Lambert-W function for constrained resource allocation in cooperative networks

Félix Brah,Jérôme Louveaux,Abdellatif Zaidi,Luc Vandendorpe

doi:10.1186/1687-1499-2011-19

Abstract

In cooperative networks, a variety of resource allocation problems can be formulated as constrained optimization with system-wide objective, e.g., maximizing the total system throughput, capacity or ergodic capacity, subject to constraints from individual users, e.g., minimum data rate, transmit power limit, and from the system, e.g., power budget, total number of subcarriers, availability of the channel state information (CSI). Most constrained resource allocation schemes for cooperative networks require rigorous optimization processes using numerical methods since closed-form solutions are rarely found. In this article, we show that the Lambert-W function can be efficiently used to obtain closed-form solutions for some constrained resource allocation problems. Simulation results are provided to compare the performance of the proposed schemes with other resource allocation schemes.

Highlights

Cooperative transmissions have attracted much attention over the last few years
We present a new result on how the Lambert-W function can be used to efficiently find closed-form solution of constrained resource allocation problems for cooperative networks
We have formulated power allocation problem to maximize the ergodic capacity under total power constraint

Summary

Introduction

Cooperative transmissions have attracted much attention over the last few years. It has been demonstrated that the benefits of multi-antenna transmission can be achieved by cooperative transmission without requiring multiple antennas at individual nodes (for example see [1-3]). The benefits of optimal resource allocation in cooperative relay networks with perfect CSI. We present a new result on how the Lambert-W function can be used to efficiently find closed-form solution of constrained resource allocation problems for cooperative networks. Most resource allocation schemes for cooperative networks require rigorous optimization processes using numerical methods since closed-form solutions are rarely found. 3, we show how the Lambert-W function is applied to a subcarrier allocation problem in WMNs. The use of the Lambert-W function to a power allocation problem in relay networks with statistical channel information is discussed in Sect. The application of the Lambert-W function to obtain a closed-form solution for resource allocation problems in wireless mesh and relay networks constitutes the principal contribution of this article

The Lambert-W function for subcarrier allocation in wireless mesh network

Findings

Conclusion