Energy-Aware Cooperative Wireless Networks with Multiple Cognitive Users

TL;DR

This paper develops energy-efficient cooperative cognitive radio networks with multiple secondary users, optimizing throughput and delay through advanced power allocation and scheduling, validated by theoretical analysis and simulations.

Contribution

It introduces a novel multi-packet transmission framework with dirty-paper coding and optimized power and scheduling policies for energy-aware cooperative networks.

Findings

Improved throughput and delay performance at lower energy costs.

Derived stability conditions and closed-form delay expressions.

Validated theoretical results with extensive simulations.

Abstract

In this paper, we study and analyze cooperative cognitive radio networks with arbitrary number of secondary users (SUs). Each SU is considered a prospective relay for the primary user (PU) besides having its own data transmission demand. We consider a multi-packet transmission framework which allows multiple SUs to transmit simultaneously thanks to dirty-paper coding. We propose power allocation and scheduling policies that optimize the throughput for both PU and SU with minimum energy expenditure. The performance of the system is evaluated in terms of throughput and delay under different opportunistic relay selection policies. Towards this objective, we present a mathematical framework for deriving stability conditions for all queues in the system. Consequently, the throughput of both primary and secondary links is quantified. Furthermore, a moment generating function (MGF) approach is employed to derive a closed-form expression for the average delay encountered by the PU packets. Results reveal that we achieve better performance in terms of throughput and delay at lower energy cost as compared to equal power allocation schemes proposed earlier in literature. Extensive simulations are conducted to validate our theoretical findings.