数控电调带通滤波器的设计与制作

Design and manufacture of digital-controlled electrically tunable bandpass filter

设计了一种新型电调谐带通滤波器,研究了数字信号控制滤波器电调谐的技术。采用数模转换器和高压运放实现数字信号与直流电压的转换;以变容二极管作为调谐元件;带通滤波器采用梳状微带线结构,并给出了结构参数。最后制作了一个由8位二进制编码控制的电调谐带通滤波器,其中心频率在300～1200MHz可调。测试结果与理论设计基本吻合。

A new type electrically tunable bandpass filter was designed, how to control the filter tuning by digital signal was investigated. The transformation between digital signal and DC voltage was made with D/A converser and high voltage amplifier; varactors were used for tuning components; the bandpass filter was a combline microstrip line one, its dimension was presented. Finally the digital-controlled electrically tunable filter has been manufactured, its center frequencies can be tuned in 300-1 200 MHz, each was controlled by 8-digit binaries. The performance of it basically coincided with the design.