Novel filter design incorporating asymmetrical junction circulators

Abstract

The authors have explored asymmetrical Y-junction circulator designs for narrowband applications. Exact circulation conditions are found for a general asymmetrical circulator. The circulator design allows the input and transmission ports to be at the same angular distance from the isolation port but not necessarily at 120 degrees C. This feature allows the suppression of high-order mode excitations in ferrite disks. This implies that a wide-stopband filter can be realized using asymmetric circulators. Due to the off-resonance bias of the ferrites, this device can be used at high power levels. >