User Association in Cache-enabled Ultra Dense Network with JT CoMP

Abstract

Coordinated Multi Point(CoMP) can be employed to reduce interference and improve network throughput in Ultra Dense Network(UDN). However, backhaul capacity is a bottleneck in achieving the goal. Fortunately, proactive caching is a promising technology to alleviate backhaul load. In a cache-enabled system with CoMP, user association is an important problem which can give prominence to its advantage. In this paper, to pursue large network throughput gain at less cost of backhaul load, we formulate user association problem as an Integer Programming(IP) problem. Given the strategy of content placement, we propose an N-Best Binary Particle Swarm Optimization(NB-BPSO) algorithm to solve the problem. Simulation results show that our algorithm improves network throughput and reduces backhaul traffic significantly compared with traditional user association schemes.