Performance evaluation of cognitive underlay multi-hop networks with interference constraint in Rayleigh fading channels perturbed by non-Gaussian noise

In this paper, the performance of regenerative decode-and-forward (DaF) cognitive multi-hop underlay networks over independent but non-identically distributed (i.n.i.d.) Rayleigh fading channels with additive white generalized Gaussian noise (AWGGN) is analyzed. Precisely, we derive exact analytical expressions for the average bit error rate (BER) of M-ary quadrature amplitude modulation (M-QAM) and M-ary phase shift keying (M-PSK). Besides, an exact expression for the average symbol error rate (SER) of M-QAM is obtained. In addition, lower- and upper-bound expressions for the end-to-end ergodic capacity is provided. Some representative numerical examples are presented to study the impact of the noise shaping parameter and average power of the interfering and secondary links on the system performance. Our obtained analytical results are supported with Monte-Carlo simulations to validate the accuracy of the analytical derivations.