The Research Of Uplink Closed Loop Power Control In TD-SCDMA System

TD-SCDMA system is interference limited, which is the third generation mobile communication system researched by China. Interference between UE and BS is the main factor for limiting capacity. Power control can reduce system interference and increase system capacity by controlling transmission power of all users. Due to uplink is more important, in this thesis uplink close-loop power control in TD-SCDMA system has been developed. Research contents in this thesis are as follows:1. Giving the clear mathematical model of close-loop power control. Analyzing the influence from step,delay and transfer error to power control performance by theory and simulations.2. An adaptive step close-loop power control (ASPC) algorithm is proposed. The adaptive step (AS) is constructed from the received historical TPCs. The ASPC algorithm is combination of the FSPC algorithms, the AS method and the DCPC algorithm. This algorithm is good at tracking channel's change, without increasing control signaling. Several modifications of the ASPC algorithm were proposed, and shown to be able to enhance the high-mobile-speed performance of the basic ASPC.3. For inspecting power control algorithm, establishing a TD-SCDMA system simulation platform. The realization of key modules and the flow of simulation are described in detail.