Research On Power Control Algorithm For Device-To-Device Communication System

In recent years, with the rapid development of wireless mobile communication technologies, the user demand for high-bandwidth, high-efficiency, high-quality and low-latency service is improved. However, limited spectrum resources become the most important factors that hinder cellular system performance, and how to improve the spectral efficiency has long been a hot topic. D2D (D2D:Device-to-device) communication system allows the terminal directly communicate by reusing cellular users resources. Therefore, it effectively increases the spectral efficiency of a cellular communication system, reduces the terminal transmission power, and solves the problem of the lack of wireless communication system spectrum resources to a certain extent. However, D2D communication mode which reuses cellular resource in the LTE network will bring co-channel interference. So how to reduce interference becomes a research focus. In order to reduce co-interference in the LTE system, resource allocate scheme, interference coordination and power control can be used. This article mainly focuses on the power control technology to reduce the interference in the system.Power control algorithm in the D2D communication system is mainly divided into open-loop power control and closed loop power control. This paper first analyzes open-loop and closed-loop power control scheme. Based on these algorithms, this article proposed a power control algorithm, which makes D2D users into high interference group and low interference group according to the pathloss, The pathloss compensation for each group is different. Simulation results show the proposed scheme has better performance compared to fractional power control scheme.