Research On Performance Of Channel Conditions And Handover In WCDMA System

With the upcoming of the commercial use of 3G, the research on performance of the 3G technology has become more urgent, the performance of 3G technology should be tested through simulation of the simulative environment. So we can get a further study to the 3G by simulation using 3G technology.In this paper, according to relevant 3GPP protocol and literature, establishing a simulation platform for physical link layer of WCDMA based on Visual Studio 6.0, so achieving the simulation of system's performance at link level in real channel condition, and discussing the impact of system performance used compressed mode. First, it expounds the principle of physical link layer of WCDMA and the implementation of each module, discusses system performance in the case of fixed delay multipath rayleigh fading channels and changeable delay multipath rayleigh channels based on birth-death model. The second part discusses the relation among switching algorithm, access load control algorithm and power control algorithm, handoff control strategy, standards and the gist of evaluating handoff algorithm, based on the above work, comparing the advantages and disadvantages of some switching algorithms and difference of hand of algorithm among WCDMA, IS-95A and IS-95B, so it is clear to see the evolution of soft handover. At last, it discusses the effect on the system capability and coverage using compression mode in hard handover during different channels, just on this foundation, a new standard based on triggering compression mode which not only switch in time but also not cause system performance rapid deterioration is proposed in the paper, that is a compressed mode of grouping periodic firing. Believe that the paper can help study hard handoff in WCDMA system to some extent.The purpose of this paper is not aimed at purely theoretical study, but getting better ready for the commercial use of 3G, meanwhile through the study of channels'environment and handover, it can provide a detailed reference for the coming large-scale engineering construction and the network optimization used to achieve the commercial use of 3G.