On the Effect of Primary User Traffic on Secondary Throughput and Outage Probability Under Rayleigh Flat Fading Channel

TL;DR

This paper analyzes how primary user traffic impacts secondary user throughput and outage probability in Rayleigh flat fading channels, deriving analytical expressions and illustrating the sensing-throughput trade-off under various interference and fading conditions.

Contribution

It provides closed-form expressions for detection probabilities and analyzes the combined effects of primary traffic, fading, and interference on secondary user performance.

Findings

Increased primary traffic degrades secondary throughput.

Deep channel fades worsen spectrum sensing performance.

Interference from primary transmitters significantly impacts outage probability.

Abstract

The effect of the primary traffic on a secondary user's (SU) throughput under Rayleigh flat fading channel is investigated. For this case, closed form expressions are derived for the average probability of detection and the average probability of false alarm. Based on these expressions, the average SU throughput under the desired signal-to-noise ratio (SNR) constraint in order to maintain the quality of the secondary link is found analytically considering the random arrival or departure of the primary user. It is shown that the spectrum sensing performance and SU throughput degrade with increase in the primary traffic and the deep fade condition of the channel over which the detection is performed. The degree of degradation in SU throughput is seen to be severed further due to the interference link from the primary transmitter to the secondary receiver. Under these detrimental effects, a sensing-throughput trade-off for SU is illustrated. Finally, the combined effect of the primary traffic, fading, imperfect spectrum sensing and the interference link from a primary transmitter is studied on the outage probability at SU.