Low-complexity interference cancellation receiver for sparse code multiple access

Sparse code multiple access (SCMA) is a proposed candidate for multiple access method in 5G telecommunication. In SCMA system, the classic receiver is message passing algorithm (MPA). MPA can reach a near optimal performance, but the computation process is complicated and time-consuming, so MPA is suitable for advanced terminal. But for simple terminal such as sensor node, large mount of calculations are difficult to bear. In this paper, we propose two interference cancellation (IC) related receivers to reduce complexity, including serial interference cancellation (SIC) and jointed serial interference cancellation with MPA algorithm (Jointed SIC-MPA). It´s important to emphasize that these two IC related algorithms are designed jointed with multi-dimensional modulation constellation design. We propose a new method to generate multi-dimensional constellation. Both of them have lower complexity compared with classic MPA receiver.