A novel receiver for uplink SCMA system

Abstract

Sparse code multiple access (SCMA) is a type of code domain non-orthogonal multiple access technology,which is regarded as a promising multiple access technology for 5G due to its excellent performance.The uplink SCMA system generally uses a message passing algorithm (MPA) in the receiver.The priori information can be inaccurated to cause an increased detection error.A novel receiver for the uplink SCMA system,called ring-MPA (R-MPA) receiver,was proposed to solve this problem,by using a joint detection process.The proposed R-MPA receiver was compared with the log-MPA receiver and the classic MPA receiver,two state-of-the-art existing schemes.Both theoretical analysis and computer simulation results show that the proposed receiver not only has a superior error performance,but also has a lower implementation complexity than these existing schemes.

Keywords

• 5G;sparse code multiple access;message passing algorithm;R-MPA;overloading factor