Sparse Code Multiple Access over Universal Filtered Multicarrier in Rapidly Time Varying Channels

In this paper, the uplink sparse code multiple access over universal filtered multicarrier (SCMA-UFMC) in rapidly time varying channels is studied. In SCMA-UFMC, each subband of UFMC is occupied by multiple users through SCMA. It is observed that the inter-band-interference can be neglected and both the inter-carrier interference and inter-user-interference are small from the equivalent frequency-domain (FD) channel of even component of received signal. Based on this observation, message passing algorithm is first employed to perform multiuser detection (MUD) by utilizing only even-component of received signal. Next, to improve the performance, a two-stage detection is further presented, where the unreliable estimates from the first-stage detection using even-component are refined by utilizing additional odd component of received signal. Finally, simulation results are given to demonstrate the performance of the proposed methods.