The Research And Simulation On Several Key Algorithms Of TD-HSUPA System

With the rapid development of global mobile data service, TD-HSUPA, a very important evolution technology of TD-SCDMA, was born due to the higher demand of data rate and delay performance of uplink path on one hand, and due to the extensive use of TD-HSDPA technology on the other hand. Although downlink service is still mainly required in current TD-SCDMA networks, the specific timing of the introduction of TD-HSUPA depends on the network behavior of the main business needs for uplink service. As service becomes integrated and diversified in future networks, TD-HSUPA is doomed to be induced with the more evident demand of uplink service. Therefore, it is particularly necessary to study TD-HSUPA key algorithms such as synchronization tracking, power control and beamforming algorithms.This paper has performed a large number of simulations on the relevant performance indicators, based on the study of synchronization tracking, power control and beamforming of these three algorithms and using the MATLAB platform. The simulation results show that for synchronization tracking and power control of these two algorithms, they should select a larger mean value forgetting factor, thus making it more conducive to track changes in channel conditions, thereby enhancing the algorithm performance. For the beamforming algorithm, the performance depends on the channel correlation of the signal transmission of the uplink and downlink subframe, while channel correlation is related with users'mobile speed, so how to select the mean value forgetting factor is dependent on users'mobile speed. If the beamforming algorithm tends to make slow-moving users get better performance, the mean value forgetting factor is inclined to range from 0.5 to 1 without consideration of fast-moving users'communication qualities. While the beamforming algorithm tends to make fast-moving users get better performance, the mean value forgetting factor is inclined to range from 0 to 0.5.