Abstract: In order to improve the QoS(Quality of Service) of users in mobile communications and to solve the problem that the total energy efficiency of the system and the quality of service of users can not be reconciled, a resource allocation scheme based on the quality of service and energy efficiency of users is proposed for the application scenario of SCMA(Sparse Code Multiple Access) downlink. The capacity and energy consumption of the system are taken as the main directions for optimisation. A greedy algorithm is used to allocate subscribers to the codebook, which is transformed into a convex optimization problem using the GDA(Generalized Dinkelbach’s Algorithm) for iterative solution. The user code book and energy consumption are calculated in rotation until the minimum user communication speed in the system changes below a preset value or reaches the maximum number of operations, so that the capacity and energy consumption of the system reach a better situation. The theoretical analysis and simulation results show that the proposed SCMA allocation scheme can effectively improve the communication rate and system energy efficiency of the users in the downlink.

Key words: sparse code multiple access (SCMA), resource allocation, codebook distribution, energy consumption