Secure Transmission With Antenna Selection in MIMO Nakagami- $m$ Fading Channels

Lifeng Wang, Maged Elkashlan, Jing Huang, Robert Schober, Ranjan K. Mallik
2014 IEEE Transactions on Wireless Communications  
This paper considers transmit antenna selection (TAS) and receive generalized selection combining (GSC) for secure communication in the multiple-input-multiple-output wiretap channel, where confidential messages transmitted from an N A -antenna transmitter to an N B -antenna legitimate receiver are overheard by an N E -antenna eavesdropper. We assume that the main channel and the eavesdropper's channel undergo Nakagami-m fading with fading parameters m B and m E , respectively. In order to
more » ... s the secrecy performance, we present a new unifying framework for the average secrecy rate and the secrecy outage probability. We first derive expressions for the probability density function and the cumulative distribution function of the signal-to-noise ratio with TAS/GSC, from which we derive exact expressions for the average secrecy rate and the secrecy outage probability. We then derive compact expressions for the asymptotic average secrecy rate and the asymptotic secrecy outage probability for two distinct scenarios: 1) the legitimate receiver is located close to the transmitter, and 2) the legitimate receiver and the eavesdropper are located close to the transmitter. For these scenarios, we present new closed-form expressions for several key performance indicators: 1) the capacity slope and the power offset of the asymptotic average secrecy rate, and 2) the secrecy diversity order and the secrecy array gain of the asymptotic secrecy outage probability. For the first scenario, we confirm that the capacity slope is one and the secrecy diversity order is m B N B N A . For the second scenario, we confirm that the capacity slope and the secrecy diversity order collapse to zero. Index Terms-Diversity combining, average secrecy rate, Nakagami-m fading, physical layer security, secrecy outage probability.
doi:10.1109/twc.2014.2359877 fatcat:7vboevghavez3k3ie6fm3v7zom