Electronically tunable microwave bandpass filters
Abstract
Combline filters with novel input and output coupling networks which enable broad-band tuning to be achieved with minimum degradation in passband performance are discussed. Explicit design formulas for these filters are presented. Computer analysis of varactor tuned combline bandpass filters including the small signal varactor equivalent circuit is presented enabling filter performance to be easily evaluated. The design and experimental performance of a varactor tuned combline filter, realized in suspended substrate stripline is described. This filter tuned from 3.2 GHz to 4.9 GHz exhibited low passband insertion loss and its performance was in close agreement with theoretical expectations.
- Publication:
-
IEEE Transactions on Microwave Theory Techniques
- Pub Date:
- September 1982
- DOI:
- Bibcode:
- 1982ITMTT..30.1354H
- Keywords:
-
- Bandpass Filters;
- Computer Aided Design;
- Electronic Control;
- Microwave Filters;
- Tuning;
- Varactor Diodes;
- Design Analysis;
- Equivalent Circuits;
- Frequency Control;
- Insertion Loss;
- Network Analysis;
- Performance Prediction;
- Electronics and Electrical Engineering