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We investigate the impact of fading correlation on the performance of the doubly dirty fading multiple access channel (MAC) with non-causally known side information at transmitters. Using Copula theory, we derive closed-form expressions for the outage probability (OP) and the coverage region under positive/negative dependence conditions. We show that a positive dependence structure between the fading channel coefficients is beneficial for the system performance, as it improves the OP and extends the coverage region compared to the case of independent fading. Conversely, a negative dependence structure has a detrimental effect on both performance metrics.

In this article, the problem of power allocation in a wireless multiple access channel with two sensors is addressed, where squared channel coefficients, and, hence, signal-to-noise ratios are assumed to have Gaussian mixture distributions and the dependence between channel coefficients is described by using copula theory. For this model, outage probability is analyzed as the objective function for formulating the power allocation, and for the product copula function or in the independent channels case, a closed form of outage probability is obtained. Considering that the corresponding optimizations do not lead to convex optimization problems, MATLAB simulation is employed to solve the power allocation problem. Various Gaussian mixture distribution parameters are exploited for the links between the sensors and the fusion center with different dependencies and the results are compared.

In this paper, we analyze the side information (SI) effect on the coverage region of the wireless multiple-access relay channel (MARC) in two different communications scenarios: SI only at one source and SI only at the relay. Aiming at this work, (I) a general achievable rate region is proved for wireless MARC with SI at one source and SI at the relay in two fading models (Rayleigh model, which has been widely studied in the literature; and Rician model the rate region of which for MARC has not been obtained before); (II) This obtained region, while including previous regions as its special cases, (a) shows the advantage of the SI known at the relay compared to the SI known at one encoder in removing the SI interference at the receiver (as seen in Theorem 2.2, Remark 2.1), and on the related coverage regions, too; and (b) can be exploited to prove corresponding coverage regions; (III) Then, the SI effect on the coverage region is scrutinized in different situations (SI only at one source and SI only at the relay), and also the differences between two fading models (Rayleigh and Rician) are investigated. (IV) Finally, theoretical findings are evaluated numerically.

In this article, a wireless wiretap channel with artificial noise assisted transmission and active eavesdropper is considered, where, wireless channel coefficients are correlated. Aiming at analyzing wireless channels correlation effects on the physical layer security, we exploit copula theory and obtain closed form expressions for the probability of positive secrecy rate, average secrecy rate, and generalized secrecy outage probability. Then, the obtained analytical results are evaluated numerically under positive dependence, independence and negative dependence correlation structures and it is shown that in different scenarios, the effect of correlated fading on the security performance can be beneficial or harmful. In this article, a wireless wiretap channel with artificial noise assisted transmission and active eavesdropper is considered, where, wireless channel coefficients are correlated. Aiming at analyzing wireless channels correlation effects on the physical layer security, we exploit copula theory and obtain closed form expressions for the probability of positive secrecy rate, average secrecy rate, and generalized secrecy outage probability. Then, the obtained analytical results are evaluated numerically under positive dependence, independence and negative dependence correlation structures and it is shown that in different scenarios, the effect of correlated fading on the security performance can be beneficial or harmful.

Information‐theoretic analysis of the communication systems performances is of practical and theoretical importance. In this article, we study side information impact on physical layer security in a Rayleigh fading wiretap channel by deriving closed‐form expressions for the average secrecy capacity (ASC), secrecy outage probability (SOP), secrecy coverage region (SCR), and specifically, the asymptotic behavior of SOP. The results, while including previous works as special cases, show that side information has positive effects over ASC and SOP, and also, it increases the SCR, as expected intuitively. Numerical evaluations have been done to support the claims. Information‐theoretic analysis of the communication systems performances is of practical and theoretical importance. In this article, we study side information impact on physical layer security in a Rayleigh fading wiretap channel by deriving closed‐form expressions for the average secrecy capacity (ASC), secrecy outage probability (SOP), secrecy coverage region (SCR), and specifically, the asymptotic behavior of SOP. The results, while including previous works as special cases, show that side information has positive effects over ASC and SOP, and also, it increases the SCR, as expected intuitively. Numerical evaluations have been done to support the claims.

This paper provides an information‐theoretic study for the additive white impulsive noise channels by considering Gaussian mixture (GM) noise model, which includes Middleton class A and ε‐mixture Gaussian models. First, three lower and two upper bounds are found for the differential entropy of complex multivariate GM distribution and these bounds are extended to the univariate GM noise of flat fading impulsive noise channels. Second, the instantaneous capacity of these channels is bounded using two lower and two upper bounds, and the ergodic capacity and outage probability of these bounds are investigated for the log‐normal fading model. Finally, the obtained bounds are numerically illustrated and their tightness is discussed for various realizations of the GM noise. The results demonstrate that the tight bounds are not the same for all considered realizations, but they are close enough and converge to each other for a specific realization. This paper provides an information‐theoretic study for the additive white Gaussian mixture (GM) impulsive noise channels. This includes three lower and two upper bounds for the differential entropy of GM distribution and, two lower and two upper bounds for the capacity of these channels. The numerical and analytical results demonstrate that the tight bounds are not the same for all realizations of GM noise, but they are close enough and converge to each other for a specific realization.