Analog Frequency Tracking Filter

Abstract

This paper propose a new type of analog adaptive filter derived as a generalization of the concept of matched filter. We conceive such a filter to track the instantaneous frequency of frequency modulated signals. Some properties of the proposed analog frequency tracking filter are established using the time-frequency representations theory. A constructive solution, based on common analog integrated circuits, is also proposed. The performance of the analog frequency tracking filter built is evaluated by measurements. Finally, some possible applications are highlighted.

Keywords

• analog circuits
• frequency modulation
• matched filters
• switched capacitors circuits
• tracking filter