宽带中频下变频系统的研究与设计

Research and Design of a Broadband Intermediate Frequency Down-Conversion System

在用于卫星通信系统的接收机的设计中,需要减少地面通信中心站上中频段变频的数量,扩大接收机系统的动态范围,以充分利用卫星转发器资源。采用ATMega128作为可编程控制器,ADF4360-8产生本振信号源,AD8343芯片作为混频器,AD8367芯片作为VGA控制器芯片,构成逻辑架构。设计并实现一种低失真宽带中频下变频器,具有时分多用、操作灵活方便等特点。

In the design of satellite communication system receivers,it is necessary to reduce the number of intermediate frequency(IF)converters at the ground communication center station and expand the dynamic range of the receiver system to fully utilize the satellite transponder resources.By employing the ATMega128 as a programmable controller,ADF4360-8 for generating the local oscillator(LO)signal source,AD8343 as the mixer,and AD8367 as the variable gain amplifier(VGA)controller chip,a logical architecture is constructed.A low-distortion wideband IF down-converter is designed and implemented,featuring time-division multiplexing(TDM),flexible operation,and convenience.