Algorithm Design And Simulation For Radio Resource Management In Td-lte System

As one of the primary standard of B3G (Beyond3G), LTE has been commercialized all over the world. As the evolution technology of TD-SCDMA, TD-LTE has got much more attention due to its flexible networking even the frequency resource is limited. In TD-LTE system, resource scheduling and inter-cell interference are the key technologies, which affluence the performance of system capacity. The studying object of RRM is air interface of wireless communication system, with its aiming to provide better coverage capacity and QoS under the limited wireless resources. Without RRM, even the advanced wireless transmission technology can not bring a good result, and may even cause the system crash down. For TDD (Time Division Duplexing) system, due to the frequency resource for uplink and downlink lies in the same frequency band and the system requires a higher level synchronization, RRM is much more important in RAN (Radio Access Network) system.Chapter1and2give a general description to TD-LTE system and some key technologies used in OFDM (Orthogonal Frequency Division Multiplexing) system, and also point out the objective of this thesis in RRM research.Scheduling and resources allocation schems for LTE traffic and control channel are introduced in chapter3. For traffic channel, an improved RAD (Required Activity Detection) method proved by simulation with BE (Best Effort) and VoIP service is proposed, which turns out could effectively support the QoS requirement for combination traffic. For the strategy of control channel scheduling and resource allocation, the effect of PCFICH and PHICH to PDCCH are taken into consideration and an equivalent data to reference signal power ration is inducted. The thesis also provides a new scheme which could adjust PDCCH power and CCE resourced collision detection. Simulation results show that the provided method can effectively improve the capacity of the control channel.Futhermore, we also analyze layer3and its related RRM problems, including ICIC (Inter-Cell interference cooperation) and LBC (Load Balance Control). Motivated by the analysis of interference problem in TD-LTE eNodes, a semi-static ICIC algorithm is proposed. This algorithm could effectively adjust resource assignment strategies according to the change status of users, so as to acquire better system performance. Studying on the principles to classify users helps to optimize the system performance. Based on3GPP specifications standards, a SFR-DICIC sceme is proposed, which combines static resource partition with ICIC information, provide better performance except for the lighter traffic case.Due to the diversity of service and increase of user, LB (Load Balance) plays a crucial role to improve the system performance. This thesis studies the LB problem in TD-LTE system. A complete LB algorithm is designed in our work. The simulation results indicate that reasonable parameter configuration is important to the LBC (LB Control) algorithm performance enhancement. The processing of LB needs the support of signaling between X2interfaces, but excessive signaling will waste the system resources. The simulation results indicate when the load is low, the system performance will not have distinct difference regardless if the LBC algorithm is activated or not. When the load becomes high, LBC can obviously improve the capability of system.Finally, a conclusion is given and direction for deeper research is pointed out.