Precoder Design And Functions Deployment Of C-RAN System Based On Wireless Fronthaul

Cloud Radio Access Network (C-RAN) is one of the key technologies in the future 5G core program, provides an effective solution to solve the energy consumption and the cost of base station, facing the traditional access network utilization and other issues. Compared to the traditional wireless access network, C-RAN system uses a centralized processing mode, the traditional base station functions are implemented in the RRH and BBU side, which enhance the cell coverage and capacity, but also improve the ability of cooperative performance of the access network and large-scale computing. However, in the C-RAN system, so the fronthaul that link between the BBU and RRH need to achieve high capacity and low latency of the target and requirement. At the same time, in the fronthaul of C-RAN, the wireless bearer scheme has advantages of abundant deployment scenarios, cost saving and easy upgrade and maintenance compared with traditional optical fiber scheme. Therefore,how to apply the wireless fronthaul better in the actual scenes is one of the biggest challenges in the C-RAN system.The main research content of this paper is how to alleviate the load and the optimization of the fronthaul transmission in the C-RAN system.In our research, we will focus on the precoding design and baseband function splitting strategy for the C-RAN system based on wireless fronthaul in the future 5G system.Firstly, we analyse the basic compositions and network architecture of C-RAN system, and introduce the three main ways of carrying fronthaul.Then through a number of communication operators and equipment manufacturers research findings, the feasibility of wireless fronthaul C-RAN technology was proved. The research challenges and new directions of C-RAN technology for wireless fronthaul are discussed.Following, aiming at the imperfect channel state information (iCSI) in wireless C-RAN fronthaul system, design the C-RAN robust precoding,through the use of robust precoding that proposed scheme can effectively save the power consumption of the system. This paper assume the wireless channels of UE to RRH and BBU to RRH fronthaul are iCSI, so analyze the of the proposed robust precoding has very good practical values. The simulation results show that the C-RAN system based on the wireless fronthaul can effectively reduce the power consumption of the C-RAN system, and also achieve the effect of reducing the outage probability.Then, the game theory is used to study and analyze the design of the baseband function splitting and deployment in the C-RAN system of the wireless fronthaul. In this paper, we first study the two typical C-RAN architectures, which are the most promising applications. According to the two different kinds of C-RAN architecture, put forward two kinds of game models, including the framework of P2P under the Cournot duopoly model and RRH cluster structure under the Nash bargaining game model.In this paper, the proposed models and the simulations are considered in the case of wireless fronthaul of iCSI. The simulation results show that the proposed Cournot duopoly game model and the Nash bargaining game model can achieve effective and accurate baseband function splitting deployment design in different scenarios.Finally, a summary of the full text is made and future research directions are discussed.