A High Power Single-Bridge SP4T Waveguide Reciprocal Ferrite Switch

Bridge-type waveguide switches using vector-rotation elements can extend the number of switched ports from two to four by incorporating orthogonal mode transducers prior to a pair of final combining hybrid tees. Rotatable ferrite half-wave plates allow efficient selection of any desired amount of reciprocal vector rotation. This paper describes the operating principle of an SP4T switch using rotatable ferrite half-wave plates in a waveguide bridge, and analyzes bandwidth vs. isolation considerations. Measured data are presented for an X-Band engineering model switch capable of handling up to 100 KW, peak RF power.