Research On Wireless Technology LTE Network Resource Allocation

With the development of technologies, wireless mobile communication technology is developed from the first generation, the analog communication, to the narrow-band digital communications. And now, it is the wide-bandwidth digital communications. Needs of people are changed from the simple voice and text to the low-bandwidth data services, and now to a variety of multimedia services. With the wireless mobile services gradually increasing, the existing 2G and 3G wireless communication networks have been unable to meet people’s needs. The 3GPP proposed LTE next-generation wireless communication network in 2004. Under the 20 MHz bandwidth, LTE can provide the maximum peak downlink rate to 100 Mbps and peak uplink rates up to 50 Mbps.This paper focuses on the resource allocation algorithm of downlink in LTE network. First, we describe the major technology-related LTE network resource allocation algorithm and summarize the characteristics of the allocation of resources. Secondly, this paper describes the design goals and research directions of the current resource allocation algorithm. Thirdly, based on the analysis of the existing radio resource allocation algorithms, this paper establishes a single-cell and multi-cell LTE network in the time domain, frequency domain and power joint resource allocation models. The salient features of the proposed model are to support a minimum rate constraint for users. Meanwhile, the over-allocation of the upper MAC buffer queue length is taken into account to avoid resource over allocated. In this paper, the decomposition method is used to solve the mixed integer programming problem, i.e., the upcoming joint resource allocation problem is decomposed into a resource block allocation under fixed power and a power control problem under fixed distribution block resource.In the phase of resource block allocation, we design an efficient resource allocation algorithm block, the Cross-layer fair greedy algorithm(CFG). This algorithm optimizes the largest carrier to interference ratio algorithm in the aspect of fairness. To meet the minimum rate constraint, the maximum and minimum allocation ideas are used. This algorithm is applied to both single-cell and multi-cell scenarios. Simulation results demonstrate that our proposed CFG algorithm can obtain good throughput performance in low complexity scenario. Compared with the BABS + ACG algorithm, the CFG algorithm can get better cell throughput in polynomial time.In the phase of single-cell power control, based on the classic water algorithm, the protection mechanism of user minimum rate constraints and the mechanism of resource limited by the MAC layer queue length are proposed. Meanwhile, a two-stage injection power control algorithm(TSWPC) is designed. Simulation results show that the TSWPC mechanism can effectively reduce the over-allocation of resources. In the phase of multi-cell power control, as LTE adds an X2 interface in inter-cell, the power limited water-filling algorithm(PLW) using power cooperative control technology is designed. This algorithm sets the upper limit of the power of a single resource block to avoid the strong inter-cell interference. And this upper limit is dynamically adjusted based on the information that indicating the quality of the resource block of the adjacent cell interactions. Simulation results indicate that in the scenes that the number of users in the community is large, the power cooperative control technology of this algorithm has a better dynamic frequency multiplexing average cell throughput performance than the SGC / RRM algorithm based on non-cooperative game.