Research On Resource Scheduling Algorithm In TD-LTE Trunking Communication System

With the the deepening of people’s understanding of the trunking communication system, demand is growing in all areas of Internet services, multimedia services and high speed data services. But traditional trunking communication system cannot meet high-bandwidth, high-rate demand, Therefore, the development of TD-LTE broadband trunking communication system becomes a hot topic. Since the performance requirements of dispatching, low latency and priority right to communicate, TD-LTE resource scheduling algorithm will no longer apply to the trunking communication system. So, what kind of resource scheduling algorithm can be better applied to TD-LTE trunking system, in which a more rational and effective utilization of spectrum resources to ensure that the group throughput and user satisfaction, become the focus of this research.For TD-LTE trunking system uplink and downlink resource allocation asymmetrical features, in the uplink, a resource allocation algorithm is designed, which is based on the performance requirements of low latency and priority of communication, which is specific to the cluster system. In the downlink, this thesis designs a resource allocation algorithm to balance throughput and user satisfaction. The main contents are as follows:(1) For TD-LTE system uplink RB resource continuity constraint, this thesis analyzes the existing RB resources continuity algorithm: FME and RME algorithm. Since FME and RME algorithms can not solve the deep-fading problems and don’t consider the constraint of MCS resulting in lower throughput, this thesis proposes a multi-extremal optimization algorithm of MME, simulation show MME algorithm can effectively solve the problem of deep fading.(2) Since the trunking system performance requirements for low latency and priority right to communicate, Firstly, resource allocation algorithm is designed based on the delay constraint in the time domain scheduler and the frequency domain scheduler using MME algorithm, and its performance is verified by simulation. Although this algorithm guaranteed throughput while reducing latency business, it’s not stable because of the frequency domain selectivity of MME algorithm.Then in order to ensure that the trunking user’s priority right of communication, SMME algorithm is designed based on resource preempted, finally, verified by simulation on the effectiveness of delay and user priority right to communicate performance.(3) In the downlink, the thesis proposes OSP algorithm based on the division of subgroup to maximize the group throughput. Compared with traditional algorithms, the proposed OSP algorithm greatly improves the group throughput. In order to further reduce the GDI of OSP algorithm, the thesis studies the sub-group division method of minimizing GDI, and puts forward the GCSP algorithm based on GDI constraint. The simulation results show that the algorithm is guaranteed group throughput while effectively reducing GDI.