Research On Control Algorithms Of WCDMA Radio Frequency Channel Gain

WCDMA base stations needs Remote Radio Unit with stable gain to keep a suitable coverage area, by this way, the base station could transmit signals with expected power, However, the concrete values of the gain of the radio frequency channel are different from each other due to various batch of devices, temperature and frequency, Therefore, it is necessary to control the gain of channels to satisfy the requirement of non-linear character of power transmission.This thesis focuses on the methods for adjusting the gain of radio frequency channels, Firstly, we introduces the way adjust the channel gain utilizing open-loop control mechanism for uplink channel. In this method, the frequency-gain correction table and temperature-gain correction table are employed. Then, the approach of adjusting the down-link channel gain via closed-loop mechanism is presented. Base on this approach, the value of channel gain correction is calculated utilizing the analog loop model of down-link channel by following three steps. Firstly, we have defined the membership function of input and output values and planar fuzzy rules. Then, using the fuzzy toolbox of MATLAB, the two-dimensional fuzzy inference engine is designed, and the gain control model based on the fuzzy control algorithms is established. Finally, the closed-loop control algorithm and fuzzy control algorithm are simulated simultaneously, by which the feasibility of fuzzy control method is proven.