A self‐matched negative group delay circuit with tunable center frequency and group delay

Abstract

A compact self-matched negative group delay circuit (NGDC) with tunable center frequency and tunable group delay (GD) is proposed. Two varactors and a variable resistor are utilized to implement the tunability of the center frequency and GD of the proposed NGDC. To verify the design concept, a tunable NGDC is designed and fabricated. The measured center frequency is tuned from 0.8 to 1.3 GHz and the measured NGD time is tuned from −1 to −10 ns. The insertion loss varies from 16.0 to 34.5 dB. In the process of tuning the center frequency and NGD time, the return losses keep better than 30 dB.