Cooperative Cognitive Relaying Under Primary and Secondary Quality of Service Satisfaction

TL;DR

This paper introduces a cooperative protocol for primary and secondary users in cognitive radio networks, utilizing secondary relays and beamforming to enhance primary and secondary QoS, with an analysis of the diversity-multiplexing tradeoff.

Contribution

It presents a novel cooperative protocol involving secondary relays and beamforming, with a linear optimization framework for QoS satisfaction in cognitive radio settings.

Findings

The protocol improves primary and secondary throughput under QoS constraints.

The optimization problem for resource allocation is linear and efficiently solvable.

The sum of secondary throughputs must not exceed primary packet reception probability.

Abstract

This paper proposes a new cooperative protocol which involves cooperation between primary and secondary users. We consider a cognitive setting with one primary user and multiple secondary users. The time resource is partitioned into discrete time slots. Each time slot, a secondary user is scheduled for transmission according to time division multiple access, and the remainder of the secondary users, which we refer to as secondary relays, attempt to decode the primary packet. Afterwards, the secondary relays employ cooperative beamforming to forward the primary packet and to provide protection to the secondary destination of the secondary source scheduled for transmission from interference. We characterize the diversity-multiplexing tradeoff of the primary source under the proposed protocol. We consider certain quality of service for each user specified by its required throughput. The optimization problem is stated under such condition. It is shown that the optimization problem is linear and can be readily solved. We show that the sum of the secondary required throughputs must be less than or equal to the probability of correct packets reception.