Next Article in Journal
An Anti-Electromagnetic Attack PUF Based on a Configurable Ring Oscillator for Wireless Sensor Networks
Next Article in Special Issue
Achieving Congestion Mitigation Using Distributed Power Control for Spectrum Sensor Nodes in Sensor Network-Aided Cognitive Radio Ad Hoc Networks
Previous Article in Journal
Ultra-Sensitive NT-proBNP Quantification for Early Detection of Risk Factors Leading to Heart Failure
Previous Article in Special Issue
Joint Resource Optimization for Cognitive Sensor Networks with SWIPT-Enabled Relay
Article Menu
Issue 9 (September) cover image

Export Article

Open AccessArticle
Sensors 2017, 17(9), 2111; https://doi.org/10.3390/s17092111

On Optimal Cooperative Sensing with Energy Detection in Cognitive Radio

Department of Electronic Engineering, Sogang University, Seoul 04107, Korea
*
Author to whom correspondence should be addressed.
Received: 2 August 2017 / Revised: 10 September 2017 / Accepted: 11 September 2017 / Published: 15 September 2017
(This article belongs to the Special Issue Cognitive Radio Sensing and Sensor Networks)
Full-Text   |   PDF [1342 KB, uploaded 19 September 2017]   |  

Abstract

In this paper, we propose an optimal cooperative sensing technique for cognitive radio to maximize sensing performance based on energy detection. In most spectrum sensing research, many cooperation methods have been proposed to overcome the sensitivity of energy detection so that both primary and secondary users are better off in terms of spectral efficiency. However, without assigning a proper sensing threshold to each sensing node, cooperation may not be effective unless the received average primary user signal-to-noise ratio (SNR) is identical. We show that equal threshold energy detection severely degrades sensing performance when cooperative sensing nodes experience diverse average SNRs, and it is not unusual for even single-node sensing to be better than cooperative sensing. To this end, based on the Neyman–Pearson criterion we formulate an optimization problem to maximize sensing performance by using optimized thresholds. Since this is a non-convex optimization problem, we provide a condition that convexifies the problem and thus serves as a sufficient optimality condition. We find that, perhaps surprisingly, in all practical cases one may consider this condition satisfied, and thus optimal sensing performance can be obtained. Through extensive simulations, we demonstrate that the proposed technique achieves a globally optimal solution, i.e., it maximizes the probability of detection under practical operating parameters such as the target probability of false alarm, different SNRs, and the number of cooperative sensing nodes. View Full-Text
Keywords: cognitive radio; cooperative sensing; energy detection; globally optimal threshold; hard decision cognitive radio; cooperative sensing; energy detection; globally optimal threshold; hard decision
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Bae, S.; So, J.; Kim, H. On Optimal Cooperative Sensing with Energy Detection in Cognitive Radio. Sensors 2017, 17, 2111.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top