Double Circulation Frequency Operation of Stripline Y-Junction Circulators

The double circulation frequency operation (DCFO) of stripline Y-junction circulators loaded with dielectric-ferrite composites is presented. The dielectric-ferrite composite is made by combining a dielectric puck with a ferrite ring. The DCFO is identified in the mode chart, and it is found that mode 1 and mode 1A, according to Davies and Cohen, play their respective roles in the circulation. Theoretical results of perfect circulation are derived, applying Bosma´s Green´s function to the junction mode impedances, and then, design and operation of the DCFO are studied. Finally, experimental examples are presented.