Content caching and spectrum allocation joint design method for NOMA wireless video multicast

The invention provides a content caching and spectrum allocation joint design method oriented to NOMA wireless video multicast. According to the method, joint allocation of cache resources, power and bandwidth resources is comprehensively considered, and the purpose is to maximize the overall video receiving quality of users in a multicast group under the constraint of multi-dimensional resources. According to the invention, the method comprises the steps: modeling spectrum allocation and layered video caching as a mixed integer linear programming problem; in order to facilitate processing, decoupling the optimization problem into a resource allocation sub-problem of intra-group spectrum constraint and cache constraint; finally, converting the resource allocation sub-problem of the intra-group spectrum constraint and the cache constraint into a knapsack problem, and designing a multicast group-oriented PSNR priority algorithm for solving. On the basis, a hierarchical content caching algorithm in a multicast g