Mixture Gamma Fading Research Articles

Performance Analysis of Outdoor THz Links Under Mixture Gamma Fading With Misalignment

Performance Analysis of Outdoor THz Links Under Mixture Gamma Fading With Misalignment

UER of various modulation schemes over SC diversity with GGD noise for EMNC

ABSTRACT Electromagnetic nano communication (EMNC) is an evolving field of modern communication technology. Terahertz imaging, sensing, food safety and security, quality control and simultaneous localisation and mapping, which all together make it a suitable use case for 6 G, are the most lively applications of EMNC. This manuscript proposes unified expressions of error rate under different modulation schemes for EMNC. For this, mixture gamma (MG) fading distribution, including almost all the fading channels, under dual selection combining (SC) diversity is developed and employed. Also, generalised Gaussian distribution (GGD), which is appropriate for the EMNC system under an aqueous medium, is employed in the analysis. Specifically, analytical expressions for BER of BPSK, M-PAM and M-QAM schemes over MG fading under dual SC diversity are derived in the presence of GGD noise. Proposed analytical expressions are numerically compared with those available in the literature without SC diversity. Comparison shows that irrespective of the value of fading severity ‘’ and/or noise shaping parameter ‘’, dual SC offers a significant improvement in BER. It is most important to mention that proposed expressions are unified in nature because a variety of results can be reproduced for different values of ‘’ and ‘’.

Approximating Ergodic Mutual Information for Mixture Gamma Fading Channels With Discrete Inputs

To evaluate the performance of wireless multi-path channels with discrete inputs, this letter investigates the ergodic mutual information (EMI) of a generalized fading type named mixture gamma distribution (MGD) under $M$ -ary quadrature amplitude modulation ( $M$ -QAM) signaling. An accurate closed-form expression for the EMI is developed to approximate the exact value. The MGD fading can be specialized into several regularly used fading cases including Rayleigh fading, Nakagami- $m$ fading, $\eta -\mu $ fading, $\kappa -\mu $ fading, and ${\mathcal {K}}_{G}$ fading, and then the corresponding closed-form EMI formulas are separately derived to measure these fadings. Compared with the Gaussian source signals based research on MGD fading, this work sheds light on the performance with discrete inputs instead of Gaussian inputs, thereby being more practical. This study can be regarded as a unified tool to evaluate the EMI with discrete inputs over arbitrary wireless channels.

Phase-Jitter based SER of MPSK Scheme over Generalised Mixture Gamma Fading

ABSTRACTExtensive literature exists for simple and exact expressions of symbol error rate (SER) over fading channels under different modulation schemes whose boundaries meet at right angles. In cases where boundaries do not meet at right angles, integrals of special function in the expressions make the exact calculation most complex. In such cases only approximate solutions are possible. Also, it is noteworthy to mention that when detection is performed with proper use of the phase (phase-jitter-based approach), noise performance of the receiver improves significantly. This paper applies phase-jitter PDF-based approach to present exact and closed-form SER expression of MPSK scheme over Mixture Gamma (MG) distribution for an arbitrary array of signal points. The proposed expression is generic as MG distribution can be approximated in almost all fading/shadowed fading channel models. As a proof to the authenticity, SERs of MPSK scheme over Rayleigh and Nakagami-m fading channels are deduced from the proposed SER over generalised MG distribution. Further, a significant improvement in SER has been achieved with phase-jitter-based approach as compared to conventional (non-phase-jitter-based) approach. Finally, to confirm the correctness of the proposed expression, results are validated through comparison with the existing results and Monte Carlo simulation.

A novel analytical model for interference estimation in CR‐enabled femtocells

SummaryCommercial, multideployed cognitive femtocell base stations (CFBSs) with cognitive capabilities are envisioned as a promising approach to meet the requirement of the higher data rate in today's wireless communications with nomadic users. However, random deployment of CFBSs results in interference between primary links, ie, the link between a macrocell base station (MBS) and macrocell user equipment (MUE), and secondary links, ie, the link between a femtocell base station (FBS) and femtocell user equipment (FUE). In this research paper, different analytical expressions for statistical measures such as cumulative distribution function of outage probability (Fout) and probability distribution function (Pout) have been proposed for the CFBS system. The fading channel for the secondary and primary links is taken as mixture gamma (MG) and Rayleigh distribution, respectively. It should be noticed that MG fading is one of the most generic fading channels and has not been included for analysis of the CFBS system to date. In addition, this paper presents average detection probability ( ) for cognitive radio (CR)–enabled femtocells or the CFBS system. The numerical analysis presents the effects of various parameters such as spatial density of CFBS nodes (λ), interference tolerance threshold (βth), and transmitting power of MBS (p) and fading parameters of the channel on Fout, Pout, and . Also, the numerical analysis shows perfect agreement with the theoretical background.

Closed Form Solution for Outage and Average Bit Error Rate of Asymmetric Relaying System

In this paper, closed form solution of outage and bit error rate (BER) is evaluated for the purpose of performance analysis of the amplify and forward relaying scheme under the asymmetric fading environment. In this dual hop system, we have used Rayleigh fading along source S to relay R and Mixture Gamma fading along relay R to destination D. First, we have derived closed form solution of outage and then we have used this derived expression for getting closed form solution of bit error rate (BER) for different kinds of modulation. Since Mixture Gamma fading channel represents many fading channels as its special case, so proposed closed form solution of outage and bit error rate may be used for analysis of outage and bit error rate under various fading scenarios. Specifically, in this paper, for analysis of outage and bit error rate (BER), we have taken Nakagami-m fading as a particular case of Mixture Gamma fading and analyzed the performance of proposed system after observing effect of fading severity factor and signal to noise ratio (SNR) on outage probability and bit error rate (BER).

Novel expressions for CEP/BEP under GGD noise for nano communication system

ABSTRACTA newly emerging branch of communication system is nano communication (NC). The NC has enabled numerous important applications, such as immune system support, drug delivery systems, nuclear, biological and chemical defence and air pollution control. However, like in any communication system in NC system also, the medium through which communication takes place introduces various impairments such as fading and noise. In this research paper, channel model 1, i.e. CM1 scenario is analysed over suitable fading channels and noise distribution. First and foremost, a new approximation for Weibull-Gamma (WG) fading distribution that is suitable for CM1 scenario is proposed. Further, suitable noise model for NC is proposed as; generalized Gaussian distribution under CM1 scenario. Furthermore, a novel expression for conditional error probability (CEP) is also presented. Finally, following the proposed CEP closed-form expressions for average bit error rate is derived over WG and Mixture Gamma fading channel in terms of Meijer’s G function. To the best of our knowledge results are novel and never reported in the literature of NC system.

Dual-Hop Amplify-and-Forward Variable Gain Relaying over Mixture Gamma Fading Channels

In this paper, we present the end-to-end performance of a dual-hop amplify-and-forward variablegain relaying system over Mixture Gamma distribution. Novel closed-form expressions for the probability density function and the moment-generation function of the end-to-end Signal-to-noise ratio (SNR) are derived. Moreover, the average symbol error rate, the average SNR and the average capacity are found based on the above new expressions, respectively. These expressions are more simple and accuracy than the previous ones obtained by using generalized-K (KG) distribution. Finally, numerical and simulation results are shown to verify the accuracy of the analytical results.