This paper proposes a high-security physical layer encryption scheme for sparse code multiple access filter bank multi-carrier (SCMA-FBMC) in weakly coupled four-mode fiber. Due to the multiplexing of four modes and overload SCMA, number users connected by proposed method is increased six times. To improve security SCMA-FBMC system, Logistic mapping parameters are employed as public key that di...

Sparse Code Multiple Access (SCMA) is a novel non-orthogonal multiple access scheme for 5G systems, in which the logarithm domain message passing algorithm (Log-MPA) is applied at the receiver to achieve near-optimum performance. However, the computational complexity of Log-MPA detector is still a big challenge for practical implementation, especially for energysensitive user equipments in the ...

Sparse code multiple access (SCMA) is a promising multiuser communication technique for the enabling of future massive machine-type networks. Unlike existing codebook design schemes assuming uniform power allocation, we present novel class SCMA codebooks which display imbalance among different users downlink transmission. Based on Star-QAM mother constellation structure and with aid genetic alg...

Mastitis is one of the most important diseases affecting production and reproductive efficiency dairy cows. The objective this study was to estimate prevalence subclinical mastitis (SCMA) its effects on performance in postpartum In a cross-sectional survey, sample cows (n = 200) within their 10-40 days milk from smallholder farms 159) were selected tested for SCMA using California Test. They cl...

Sparse code multiple access (SCMA), as a code-domain non-orthogonal (NOMA) scheme, has received considerable research attention for enabling massive connectivity in future wireless communication systems. In this paper, we present novel codebook (CB) design SCMA based visible light (VLC) system, which suffers from shot noise. particular, introduce an iterative algorithm designing and optimizing ...

The Third Generation Partnership Project (3GPP) and the International Telecommunication Union (ITU) identified technical requirements that fifth generation of mobile communications networks (5G) had to meet; within these parameters are following: an improved data rate a greater number users connected simultaneously. 5G uses non-orthogonal multiple access (NOMA) increase simultaneously users, by...

The reconfigurable intelligent surface (RIS)-assisted sparse code multiple access (RIS-SCMA) is an attractive scheme for future wireless networks. In this letter, the first time, RIS phase shifts of uplink RIS-SCMA system are optimized based on alternate optimization (AO) technique to improve received signal-to-noise ratio (SNR) a discrete set shifts. model formulated utilize AO algorithm. For ...

The sparse code multiple access (SCMA) scheme is a Non-Orthogonal Multiple Access (NOMA) type of that used to handle the uplink component mobile communication in current generation. A need 5G network ability more users. To accommodate this, SCMA allows each user deploy variety sub-carrier broadcasts, and several consumers may contribute same frequency using superposition coding. approach, toget...

The Wiener index W(G) of a connected graph G is defined as the sum of the distances between all unordered pairs of vertices of G. The eccentricity of a vertex v in G is the distance to a vertex farthest from v. In this paper we obtain the Wiener index of a graph in terms of eccentricities. Further we extend these results to the self-centered graphs.