CG-SCMA Codebook Design Based on Maximized Euclidian Distance

Sparse code multiple access (SCMA) is a multi-dimensional codebook based on class of non-orthogonal (NOMA) technologies enabling the delivery resource elements to numerous users in 5G wireless communications without increasing complexity. This paper proposes computer-generated sparse (CG-SCMA) technique, where minimum Euclidian distance (MED) star 16-point quadrature amplitude modulation maximized by CG-SCMA, thus creating complex SCMA optimizing difference between first and other radiuses over rotated constellations. To specify most suitable values for this constellation, it divided into four sub-constellations using trellis coded (TCM) an effort optimize MED. The new has with MED 3.85, 2.26, respectively. Application message passing algorithm (MPA) ensures low complexity decoding process.