On Secrecy Analysis for D2D Networks over alpha-µ Fading Channels with Randomly Distributed Eavesdroppers

In this paper, we study the behavior of legitimate device-to-device (D2D) transmission links when intercepted by randomly distributed eavesdroppers. To account for both large-scale and small-scale α- μ signal fading at the same time, the k-th best eavesdropper is introduced, which is modelled via a path-loss process with small-scale fading. In order to assess the mathematical representation of the interception behavior, as well as the outage event, the probability of interception Pint and the secrecy outage probability Pout are consequently targeted in the context of this paper. The probability density function (PDF) and the cumulative distribution function (CDF) of the received signal-to-noise ratio (SNR) for the k-th best eavesdropper are first computed. Benefiting from the obtained PDF and CDF, Pint and Pout are thereafter derived and fit into a closed-form expression in terms of the univariate and bivariate Fox's H-functions, respectively. Finally, Monte-Carlo simulation outcomes are provided for the purpose of verifying the precision of our analytical results. Moreover, the effects of the density of eavesdroppers, the fading parameters and the path-loss exponent on the probability of interception are also explored. Interestingly, the conceptual proposal of the k-th best eavesdropper is proved to be comprehensive, and the legitimate D2D link is largely threatened by the 1-st best eavesdropper.