Joint Content Push and Transmission in NOMA With SWIPT Caching Helper
Xuewei Zhang, Tiejun Lv, Yuan Ren, Zhipeng Lin · IEEE Communications Letters · 2020
This letter investigates the joint content push and transmission design relying on the cache-enabled helper. The helper is also equipped with the function of simultaneous wireless information and power transfer. With the help of non-orthogonal multiple access (NOMA) technique, we propose a two-stage transmission scheme. Under the minimum quality of service requirements, the sum rate optimization problem is formulated. Owing to the non-convexity nature of this problem, a series of approximation techniques, such as semi-definite relaxation, successive convex approximation and arithmetic-geometric mean inequality, are employed, after which the original optimization problem is converted into the convex form. Simulation results manifest the fast convergence property of the proposed algorithm, and demonstrate the superiority of the NOMA-based two-stage transmission strategy compared with a benchmark scheme.