| With the fast development of the mobile Internet, the number of mobile devices and data traffic are increasing rapidly at an explosive speed. As a result, the existing LTE Network is faced with an extreme challenge. Confronted with enormous amounts of connected devices and more severe service requirements, the next mobile communication system should meet with the high capacity, high transmission rate and low transmission delay. Mobile network’s performance can be promoted by means of improving a series of key technology. However, due to the limitation of LTE Network architecture, just developing the wireless technology can hardly bring expected performance gain. In order to approach these challenges, the future 5G system should make breakthrough in both the reconstruction of the network architecture and the wireless technology.In this paper, research is based on our existing access network structure since the related key technology largely determine the performance of the future network, because the assess network contains both scheduling and distribution of time-frequency resources and wireless technology in Physical Layer. Making use of the network virtualization technology, we design an access network structure that can meet future 5G’s requirements, and based on which, a wireless resources scheduling and distribution scheme is proposed and the MIMO precoding technology has been deeply researched. The detailed contents are as follows.1) Design the decoupling scheme of control plane and data plane in the access network. In order to benefit from the centralized scheduling, we modularize the data processing functions and centralize the control functions in the access network protocol stack. Data processing of the three sublayers located in Data Link Layer and the lower Physical Layer have been split into corresponding function modules while a centralized controller has been generated to provide control functions. The presented access structure can flexibly adapt to the future diverse service scenario and the centralized scheduling management of resource could improve its performance.2) Based on the new proposed access structure, studying wireless resources distribution schemes and scheduling algorithms. Differ from static resource allocation in a single cell, the controller designed above can manage several adjacent cells centrally and apply the joint resource allocation, which could increase the spectral efficiency. In consideration of different QoS features, we propose MTSS scheduling algorithm that based on proportional fairness algorithm, by means of setting different weighting factors, the presented scheduling algorithm can improve the user experience as well as guaranteeing system throughput.3) Wireless technology in Physical Layer is also a critical factor that can affect the access network’s performance. In the future, 5G network would have a trend of deploying massive antenna arrays to improve the system capacity. However, in the multiple antenna MIMO system, the correlation between channels is still a main factor that can dramatically affect the system’s performance. This paper proposes an improved precoding algorithm based on THP, which can improve the precoding performance in two aspects. On the one hand, sequencing and scheduling the users to reduce the correlation between channels which based on new access architecture, On the other hand, designing modulo operation method to reduce modulo loss when applying precoding algorithm. The performance of precoding could be enhanced under the scenario of high correlation between channels with the improvement of these two kinds of algorithm. |
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