大动态宽带数字中频AGC系统的设计  

Design of a Large Dynamic Range and Broad Band Digital IF AGC System

作　　者：曹鹏 费元春[1] 

机构地区：[1]北京理工大学信息科学技术学院电子工程系,北京100081

出　　处：《北京理工大学学报》2003年第5期613-616,共4页Transactions of Beijing Institute of Technology

基　　金：国家部委预研项目(002404050302)

摘　　要：根据数字中频接收机对自动增益控制(AGC)电路的增益调节范围、调节步长及精度、工作频率范围和响应速度等要求,分析了AGC系统中3种典型可变增益放大器存在的不足,并利用新推出的数字可变增益放大器(DVGA)芯片AD8369设计了数字AGC系统,并给出了基于FPGA的数字AGC控制电路的算法.该系统使复杂的AGC控制要求在数字部分可以容易地得到实现,且其具有快速收敛和精确的稳态响应等优点.Based on the requirements to digital IF receiver on their gain tuning range, step width and accuracy, frequency range as well as response speed of AGC circuits, the paper analyses the drawbacks of three kinds of typical variable gain amplifiers for the AGC system, and designs a digital AGC system, using a new digital VGA IC —— the AD8369 produced by ADI Inc. The paper provides a signal processing circuit and algorithm based on FPGA. The digital AGC system has its virtues in having fast and exact stablestate response. It can eaisly realize very complex AGC.

关 键 词：数字自动增益控制 数字中频接收机 数字可变增益放大器 

分 类 号：TN850.3[电子电信—信息与通信工程]