Study on the Co-Existence of 20ms TTI and 5ms TTI in E-DCH of TD-SCDMA HSUPA

The wireless link with fixed parameters is subject to time-varying channel, and the battery energy is limited in mobile terminals. Thus we consider the co-existence of 20 msTTI and 5 ms TTI in E-DCH of TD-SCDMA HSUPA. In this paper, based on the comparative study on the link performances with different TTI and the analysis on the link simulation results, we discuss the different TTI´s influence on the terminal power consumption. Furthermore, the system level performances of semi-static TTI and traditional single TTI configurations are compared. Finally the conclusions are drawn: 20 ms and 5 msTTI should co-exist in TD-SCDMA HSUPA, and be adopted respectively in different channel condition to save the terminal power. The data throughput of semi-static TTI configuration is greater than those of both single TTI configurations, and the semi-static TTI selection between 20 ms and 5 ms is implemented according to the moving speed of a specific UE.