Digital AGC Circuit Design based on FPGA

Abstract

Users' demand for broadband wireless and mobile is increasing, making wireless broadband access technology WiMAX, arise at the historic moment, rapid development, has become the focus of attention in the industry these two years. In this paper, based on the WiMAX transmission standard 802.16D, the AGC of channel demodulation in WiMAX receiver is described in detail. Firstly, the basic components and main characteristic indexes of the AUTOMATIC gain control system are introduced, and the output formula of AGC model is obtained through the analysis of a step-type AGC. Then the adc and AGC circuits in THE AGC system in the WiMAX receiver are introduced and analyzed theoretically. In this paper, SPW model is used to analyze the algorithm of the basic structure of AGC circuit. Combined with the simulation results, AGC circuit is explained in detail and parameters are explained. Finally, the verification results based on SPW and FPGA are given. The individual performance test of AGC is carried out through SPW, and combined with the performance test of the simulation system, it shows that AGC can work in cooperation with other modules of the system. In FPGA test, it can be proved that AGC can also work well with Verilog.