| 摘要 |
A system for selecting an initial value for an automatic gain control (AGC) signal is disclosed. The system may be applied where at least two base stations (BTS) communicate with a mobile unit, including 2G (GSM) and 3G (UMTS) networks. Each base station includes means for transmitting a signal including location co-ordinates and power level data of the at least two base stations. The mobile device includes means for receiving the signal from a first base station and means for measuring the received power level from the first base station. The mobile device also includes means, such as a global positioning system (GPS) receiver, for determining its own location. The mobile includes means for periodically receiving signals from a second base station, e.g. during transmission gap lengths (TGLs). The mobile then predicts the initial AGC value to apply to signals received from the second base station in dependence on the relative locations of the mobile device and the first and second base stations, the received power level of the signal from the first base station and the known transmission power of the first and second base stations. The system allows a 3G / 2G dual mode terminal to switch to GSM. The faster AGC action increases battery life. |
