Cognitive Access Protocol for Alleviating Sensing Errors in Cognitive Multiple-Access Systems

TL;DR

This paper introduces a new cognitive access protocol for shared channels that reduces sensing errors and improves secondary user throughput in primary-secondary systems.

Contribution

The paper proposes a novel secondary access protocol that enhances detection accuracy and optimizes channel access timing to maximize secondary throughput.

Findings

Significant increase in secondary throughput with the proposed protocol.

Effective reduction of sensing errors in primary channel detection.

Improved primary queue stability and delay performance.

Abstract

This letter studies a time-slotted multiple-access system with a primary user (PU) and a secondary user (SU) sharing the same channel resource. We propose a novel secondary access protocol which alleviates sensing errors and detects the availability of primary channels with the highest ability of detection. Under the proposed protocol, the SU may access the channel at one of a predefined instants within the time slot each of which associated with a certain access probability that changes based on the sensing outcome. There is also a possibility of accessing the channel at the beginning of the time slot without channel sensing. The optimization problem is stated such that the secondary throughput is maximized under stability of the primary queue and a constraint on the primary queueing delay. Numerical results demonstrate the beneficial gains of the proposed protocol in terms of secondary throughput.