Sparse Code Multiple Access Decoding Using Message-Passing Algorithm

In no time, 4G will be replaced by 5G. Furthermore, 5G still uses the Orthogonal Frequency Division Multiple Access schemes. However, Orthogonal Frequency Division Multiple Access has shortcomings in terms of massive connectivity, so a new scheme is needed to replace Orthogonal Frequency Division Multiple Access for 5G. So, this paper discusses the performance evaluation of the Sparse Code Multiple Access for 5G. In addition to the Orthogonal Frequency Division Multiple Access, a message-passing algorithm can also be used to decode Sparse Code Multiple Access messages so they can deal with large amounts of traffic. If the amount of traffic is large, it can accommodate big number of users in the use of 5G. The message-passing algorithm can meet 5G specifications, so it is suitable for 5G use. The performance of Sparse Code Multiple Access will confirm its usability for the 5G system. So, the message-passing algorithm can detect the user information on Sparse Code Multiple Access, to increasing complexity and to find bit error rate in the algorithm. This paper uses the message-passing algorithm to test the bit error rate on six types of codebooks. From all the codebooks, the codebook with smallest bit error rate is best codebook to choose for Sparse Code Multiple Access.