Network Coding Design Applied To The D2D Communication System

D2D(Device to Device)communication system is one of the important parts of mobile communication systems in 5G(fifth generation)communication systems,which can improve the utilization of wireless spectrum,and is also an effective mean to increase the communication capacity of the mobile network.But the existing researches mainly focus on the transmission mode of reusing uplink resources,however,due to the high power and interference of the base station in D2 D reusing downlink,the research is very lack in cellular downlink.This paper research mainly for sprectrum resource reusing in downlink D2 D communication system,which apply a network coding design that can against the interference in transmission,the transmission performance of the base station,the D2 D user and cellular user are studied by the relay and the transmission time slot division,we establish different objects of power,transmission distance and the coding modulation simiulate model,which provides a meaningful reference for enriching the wireless frequency reusing system of D2 D communication system.The main research contents include: Two reusing modes of D2 D communication system,application of interference suppression in network coding,two main designs of complex field network coding(parameterized space-time coding matrix and golden space-time coding matrix),we will bulid model of complex field network coding in D2 D communication system reusing sprectrum resource in cellular downlink.The simulation results show that the complex field network coding design can eliminate the interference which caused by the large power station effectively,frequency resources,so that users can effectively reuse downlink spectrum resource in relay network;Through the design of network coding,the transmission also won two order classification gain,reducing system's byte error rate(BER).