SCMA with new codebook design

Abstract

Sparse code multiple access (SCMA) is one of the promising non-orthogonal multiple access which utilizes iterative message passing algorithm (MPA) as decoding technique. This paper discusses about, basics of SCMA, mapping of information to codebooks, codebook structure and functioning of receiver. In SCMA, each user has their own codebook. But the issue is to design codebook for each user. This paper presents one new near optimal solution for codebook design for better performance. Enhancement in codebook design by taking constellations with minimum Euclidean distance can give better results with no need of channel encoder.