Research On Resource Management Algorithm In Cellular And Device-To-Device Communication Network

In recent years, smart phones, tablet computers and a variety of new applications appear. With the dramatic growth of communication user terminal, mobile data usage, mobile video service in particular, has increased significantly. Mobile communications require the higher data transfer rates. For future cellular networks, high quality voice services cannot meet the user’s requirement. The system must be able to supply large quantities of data transmission services. Thus, we need to further increase system capacity and high-speed data rate coverage, but traditional cellular networks cannot meet this requirement. The direct communication (Device-to-Device, D2D) network has been introduced to improvement the system performance.However, the direct link D2D communication may be limited in practice because of long distance, poor propagation medium and cellular interference, etc. Therefore, multi-hop D2D communication has been proposed to extend the capability of D2D system. The proper routing algorithm can produce significant impact on multi-hop D2D system, however it still lacks recognized routing algorithm which can be suitable for multi-hop D2D system. Furthermore, channel reusing and power allocation are essential to improve the energy-efficiency of multi-hop D2D system, but existing routing algorithms seldom take them into account.In this paper, the main work is as follows:1. A novel energy-efficient multi-hop routing algorithm is investigated for multi-hop D2D system by jointly optimizing channel reusing and power allocation. Firstly, the energy-efficient multi-hop routing problem is formulated as a combinatorial optimization problem. Secondly, to obtain a desirable solution with reasonable computation cost, a heuristic multi-hop routing algorithm is presented to solve the formulated problem and achieve a satisfactory energy-efficiency performance. Finally, simulation results are analyzed and show the effectiveness of the proposed routing algorithm.2. Fractional Frequency Reuse (FFR) has been introduced into D2D communications networks for interference management. It can effectively enhance the throughput and the outage probability of the system. This paper analyzes the cellular networks of FFR technology in combination with D2D applications. And the FFR dynamic spectrum allocation and FFR optimal threshold scheme is descript in detail. Finally, simulation results are analyzed and show the good performance of the system.