Performance Analysis of NOMA-based Cooperative Relaying in α - μ Fading Channels

Non-orthogonal multiple access (NOMA) is widely recognized as a potential multiple access technology for efficient radio spectrum utilization in the fifth-generation (5G) wireless communications standard. In this paper, we study the average achievable rate and outage probability of a cooperative relaying system (CRS) based on NOMA (CRS-NOMA) over wireless links governed by the α-μ generalized fading model; here α and μ designate the nonlinearity and clustering parameters, respectively, of each link. The average achievable rate is represented in closedform using Meijer’s G-function and the extended generalized bivariate Fox’s H-function (EGBFHF), and the outage probability is represented using the lower incomplete Gamma function. Our results confirm that the CRS-NOMA outperforms the CRS with conventional orthogonal multiple access (CRS-OMA) in terms of spectral efficiency at high transmit signal-to-noise ratio (SNR). It is also evident from our results that with an increase in the value of the nonlinearity/clustering parameter, the SNR at which the CRS-NOMA outperforms its OMA based counterpart becomes higher. Furthermore, the asymptotic analysis of the outage probability reveals the dependency of the diversity order of each symbol in the CRS-NOMA system on the α and μ parameters of the fading links.

[1]  H. Vincent Poor,et al.  Relay Selection for Cooperative NOMA , 2016, IEEE Wireless Communications Letters.

[2]  A. M. Mathai,et al.  The H-Function: Theory and Applications , 2009 .

[3]  Linglong Dai,et al.  On the Performance of NOMA-Based Cooperative Relaying Systems Over Rician Fading Channels , 2017, IEEE Transactions on Vehicular Technology.

[4]  H. Vincent Poor,et al.  Application of Non-Orthogonal Multiple Access in LTE and 5G Networks , 2015, IEEE Communications Magazine.

[5]  P. R. Nelson The algebra of random variables , 1979 .

[6]  Kostas Peppas,et al.  A New Formula for the Average Bit Error Probability of Dual-Hop Amplify-and-Forward Relaying Systems over Generalized Shadowed Fading Channels , 2012, IEEE Wireless Communications Letters.

[7]  Mohamed-Slim Alouini,et al.  Secrecy Capacity Analysis Over α-μ Fading Channels , 2017, IEEE Commun. Lett..

[8]  M.D. Yacoub,et al.  The $\alpha$-$\mu$ Distribution: A Physical Fading Model for the Stacy Distribution , 2007, IEEE Transactions on Vehicular Technology.

[9]  Victor Adamchik,et al.  The algorithm for calculating integrals of hypergeometric type functions and its realization in REDUCE system , 1990, ISSAC '90.

[10]  Wei Yi,et al.  Approximation to independent lognormal sum with α-μ distribution and the application , 2015, Signal Process..

[11]  H. Vincent Poor,et al.  Multiple Access Techniques for 5G Wireless Networks and Beyond , 2018 .

[12]  K. Gupta,et al.  An integral involving generalized function of two variables , 1972 .

[13]  George K. Karagiannidis,et al.  A Survey on Non-Orthogonal Multiple Access for 5G Networks: Research Challenges and Future Trends , 2017, IEEE Journal on Selected Areas in Communications.

[14]  In-Ho Lee,et al.  Capacity Analysis of Cooperative Relaying Systems Using Non-Orthogonal Multiple Access , 2015, IEEE Communications Letters.