Weighted Soft Decision for Cooperative Sensing in Cognitive Radio Networks

TL;DR

This paper proposes a weighted cooperative spectrum sensing method for cognitive radio networks that improves sensing accuracy and spectrum utilization by considering spatial variation and user contribution, using simple energy detectors.

Contribution

It introduces a novel weighted cooperative sensing technique that accounts for spatial variation and enhances robustness with minimal complexity.

Findings

Increases sensing accuracy and spectrum utilization.

Offers greater robustness to noise uncertainty.

Reduces operational complexity with simple energy detectors.

Abstract

Enhancing the current services or deploying new services operating in RF spectrum requires more licensed spectrum which may not be provided by the regulatory bodies because of spectrum scarcity. On the contrary, recent studies suggest that many portions of the licensed spectrum remains unused or underused for significant period of time raising the issue of spectrum access without license in an opportunistic manner. Among all the spectrum accessing techniques, sensing based methods are considered optimal for their simplicity and cost effectiveness. In this paper, we introduce a new cooperative spectrum sensing technique which considers the spatial variation of secondary (unlicensed) users and each user's contribution is weighted by a factor that depends on received power and path loss. Compared to existing techniques, the proposed one increases the sensing ability and spectrum utilization, and offers greater robustness to noise uncertainty. Moreover, this cooperative technique uses very simple energy detector as its building block thereby reduces the cost and operational complexity.