Resource allocation strategy in SCMA based multiple access system

The fifth generation (5G) communication system is expected to support various applications and devices. Sparse code multiple access (SCMA) is a competent non-orthogonal multiple access technology for 5G wireless communication networks which can accommodate heavy connections with different user requirement for different applications. In addition, people's requirement on wireless communications of high quality, large data rate and functional diversification has grown swiftly in the last few years. Aiming to achieve high speed packet data transmission in scarce spectrum resource and maximize system throughput under the QoS (Quality of Service) constraint, appropriate resource allocation strategy is extremely needed. In this paper, a SCMA based downlink resource allocation strategy is designed and two radio resource allocation algorithms are applied into the novel strategy, namely, PF (Proportional Fair) algorithm and M-LWDF (Modified Largest Weighted Delay First) algorithm. Simulation results show that compared with OFDM based resource allocation strategy, the SCMA based resource allocation strategy can improve system throughput, reduce packet loss rate and latency, and user fairness can also be guaranteed.