A Novel LSB Discriminator for a 5 bit IFM Subsystem Based on Microstrip Band-Stop Filter

Abstract

The authors have studied a new way to design IFM (Instantaneous Frequency Measurement) subsystem. The method is based on band-stop filters. The IFM uses rectangular open loop resonators instead of delay lines. The resonance frequency is adjusted by resonator perimeter, that must be half guided wavelength, and also by coupling distance between the resonators and the main transmission line. A LSB (least significant bit) discriminator of an IFM subsystem with resolution of 62.5 MHz is designed. The device has been fabricated on RT6010.2 substrate of thickness h=1.27 mm. A full wave EM simulator is used to obtain the frequency response.