Error exponent analysis of energy-based bayesian spectrum sensing under fading channels

Gurugopinath, Sanjeev and Murthy, Chandra R and Sharma, Vinod (2011) Error exponent analysis of energy-based bayesian spectrum sensing under fading channels. In: 2011 IEEE Global Telecommunications Conference (GLOBECOM 2011), 5-9 Dec. 2011, Houston, TX, USA.

PDF Glo_Tele__Con_1_2011.pdf - Published Version Restricted to Registered users only Download (170kB) | Request a copy

Abstract

This paper analyzes the error exponents in Bayesian decentralized spectrum sensing, i.e., the detection of occupancy of the primary spectrum by a cognitive radio, with probability of error as the performance metric. At the individual sensors, the error exponents of a Central Limit Theorem (CLT) based detection scheme are analyzed. At the fusion center, a K-out-of-N rule is employed to arrive at the overall decision. It is shown that, in the presence of fading, for a fixed number of sensors, the error exponents with respect to the number of observations at both the individual sensors as well as at the fusion center are zero. This motivates the development of the error exponent with a certain probability as a novel metric that can be used to compare different detection schemes in the presence of fading. The metric is useful, for example, in answering the question of whether to sense for a pilot tone in a narrow band (and suffer Rayleigh fading) or to sense the entire wide-band signal (and suffer log-normal shadowing), in terms of the error exponent performance. The error exponents with a certain probability at both the individual sensors and at the fusion center are derived, with both Rayleigh as well as log-normal shadow fading. Numerical results are used to illustrate and provide a visual feel for the theoretical expressions obtained.

Item Type:	Conference Paper
Publisher:	IEEE
Additional Information:	Copyright of this article belongs to IEEE. USA
Keywords:	Error Exponents;Energy Detection;Spectrum Sensing;Bayesian Framework
Department/Centre:	Division of Electrical Sciences > Electrical Communication Engineering
Date Deposited:	26 Mar 2013 09:49
Last Modified:	26 Mar 2013 09:49
URI:	http://eprints.iisc.ac.in/id/eprint/46103

Actions (login required)

View Item