Outage Probability of Cognitive Relay Networks with Interference Constraints

Abstract

This paper evaluates the outage probability of cognitive relay networks with cooperation between secondary users based on the underlay approach, while adhering to the interference constraint on the primary user, i.e., the limited amount of interference which the primary user can tolerate. A relay selection criterion, suitable for cognitive relay networks, is provided, and using it, we derive the outage probability. It is shown that the outage probability of cognitive relay networks is higher than that of conventional relay networks due to the interference constraint, and we quantify the increase. In addition, the outage probability is affected by the distance ratio of the interference link (between the secondary transmitter and the primary receiver) to the relaying link (between the secondary transmitter and the secondary receiver). We also prove that cognitive relay networks achieve the same full selection diversity order as conventional relay networks, and that the decrease in outage probability achieved by increasing the selection diversity (the number of relays) is not less than that in conventional relay networks.Index Terms-Cognitive relay networks, outage probability, selection diversity.

Secrecy analysis of cognitive radio network with MS-GSC/MRC scheme

“…It indicates that the influence of primary interference at secondary nodes is already assumed in the variance N 0 . Thus, the effect of interference is adjusted in the noise statistics at B and ER [29,30]. The instantaneous SNR of the main channels and eavesdropper's channel is given by…”

On the performance of future full-duplex relay selection networks

“…Also, n k and n d denote the complex additive white Gaussian noise components at the k th relay and the destination, with variance σ 2 k and σ 2 d , respectively. As commonly assumed in the literature, for instance in [18], we assume the relays are clustered somewhere between the source and the destination. Hence, the distances among the relays are much shorter than those between the relays and the source/destination.…”

Performance analysis of MIMO cognitive amplify‐and‐forward relay networks with orthogonal space–time block codes

“…Hence, achieving high data rates with reliable transmission is a major challenge for a wireless communication system design. Recently, the studies of cognitive radio (CR) technology and cooperative techniques have emerged as promising approaches to improve the efficiency of frequency spectrum utilization, to enhance the transmission reliability, and to extend the coverage [1][2][3][4][5][6][7][8][9][10][11]. Specifically, the literature [1][2][3] provided several important aspects of a cognitive relay network (CRN) such as interference temperature estimation, spectrum hold detection, and dynamic spectrum management.…”

“…In [4,5], power allocation strategies for CRNs with multiple relays have been proposed to optimize throughput of CRNs. Furthermore, the works of Han et al [6], Si et al [7], and Lee et al [8] investigated system performance in terms of outage probability and symbol error rate (SER) for cognitive decode-and-forward relay networks under interference constraints. In [9], the performance of cognitive amplify-and-forward (AF) relay networks with selection combining (SC) was investigated.…”