Antenna Selection in Interference-Constrained Underlay Cognitive Radios: SEP-Optimal Rule and Performance Benchmarking

Sarvendranath, Rimalapudi and Mehta, Neelesh B (2013) Antenna Selection in Interference-Constrained Underlay Cognitive Radios: SEP-Optimal Rule and Performance Benchmarking. In: IEEE TRANSACTIONS ON COMMUNICATIONS, 61 (2). pp. 496-506.

PDF ieee_tra_com_61_2_496_2013.pdf - Published Version Restricted to Registered users only Download (529kB) | Request a copy

Abstract

In the underlay mode of cognitive radio, secondary users are allowed to transmit when the primary is transmitting, but under tight interference constraints that protect the primary. However, these constraints limit the secondary system performance. Antenna selection (AS)-based multiple antenna techniques, which exploit spatial diversity with less hardware, help improve secondary system performance. We develop a novel and optimal transmit AS rule that minimizes the symbol error probability (SEP) of an average interference-constrained multiple-input-single-output secondary system that operates in the underlay mode. We show that the optimal rule is a non-linear function of the power gain of the channel from the secondary transmit antenna to the primary receiver and from the secondary transmit antenna to the secondary receive antenna. We also propose a simpler, tractable variant of the optimal rule that performs as well as the optimal rule. We then analyze its SEP with L transmit antennas, and extensively benchmark it with several heuristic selection rules proposed in the literature. We also enhance these rules in order to provide a fair comparison, and derive new expressions for their SEPs. The results bring out new inter-relationships between the various rules, and show that the optimal rule can significantly reduce the SEP.

Item Type:	Journal Article
Publication:	IEEE TRANSACTIONS ON COMMUNICATIONS
Publisher:	IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Additional Information:	Copyright for this article belongs to the IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, USA.
Keywords:	Cognitive radio; underlay; antenna selection; diversity techniques; fading channels; symbol error probability; average interference constraint
Department/Centre:	Division of Electrical Sciences > Electrical Communication Engineering
Date Deposited:	15 Apr 2013 11:41
Last Modified:	15 Apr 2013 11:41
URI:	http://eprints.iisc.ac.in/id/eprint/46400

Actions (login required)

View Item