Outage Analysis for Underlay Cognitive Networks Using Incremental Regenerative Relaying

• Published in: IEEE transactions on vehicular technology Vol. 62; no. 2; pp. 721 - 734
• Main Authors: Tourki, K., Qaraqe, K. A., Alouini, M-S
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.02.2013; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Codes; Cognitive radio; Electrical engineering. Electrical power engineering; Electrical power engineering; Exact sciences and technology; Fading; Fault tolerance; Incremental regenerative relaying; Interference channels; Mathematical analysis; Networks; Operation, maintenance, reliability; Operation. Load control. Reliability; outage analysis; Outages; Power networks and lines; Probability density function; Quality of service; Radiocommunication specific techniques; Radiocommunications; Receivers; Regenerative; Relay; Relaying; Relays; Signal to noise ratio; Studies; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); underlay cognitive networks; Relaying; outage analysis; Parameter estimation; Relay; Current source converter; Scalability; Power system stability; Regenerative process; Fault tolerance; Channel estimation; Distribution function; Incremental regenerative relaying; Fault tolerant system; Fading channels; Outage; Rayleigh channels; Cooperative systems; Analytical method; System simulation; Transmission rate; Reliability; underlay cognitive networks; Service quality; Radio communication; Software radio; Signal to noise ratio
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/TVT.2012.2222947

Cooperative relay technology has recently been introduced into cognitive radio (CR) networks to enhance the network capacity, scalability, and reliability of end-to-end communication. In this paper, we investigate an underlay cognitive network where the quality of service (QoS) of the secondary link is maintained by triggering an opportunistic regenerative relaying once it falls under an unacceptable level. Analysis is conducted for two schemes, referred to as the channel-state information (CSI)-based and fault-tolerant schemes, respectively, where different amounts of CSI were considered. We first provide the exact cumulative distribution function (cdf) of the received signal-to-noise ratio (SNR) over each hop with colocated relays. Then, the cdf's are used to determine a very accurate closed-form expression for the outage probability for a transmission rate R . In a high-SNR region, a floor of the secondary outage probability occurs, and we derive its corresponding expression. We validate our analysis by showing that the simulation results coincide with our analytical results in Rayleigh fading channels.