JPS5574204A - Open type branching filter using band block filter - Google Patents

Abstract

PURPOSE:To increase the frequency characteristics with low loss by making orthogonal the polarized wave of electromagnetic waves incoming with that reflected at the band block filter and picking up the passing band returned to the input terminal from other terminals. CONSTITUTION:The electromagnetic waves of horizontal polarized waves are emitted from the input terminal 1, pass through the polarized separator 3 and separated equally into two at the hybrid 6. Further, one is reflected and converted into the circular polarized waves at the circular polarized wave generator 4 and phase is converted at the reflection type multiresonator 12, and the waves are reflected and returned to the generator 4, where they are converted into the horizontal polarized waves incoming and the vertical polarized waves orthogonal to it and go to the hybrid 6. On the other hand, the electromagnetic waves passing through the hybrid 6 return to the hybrid 6 similarly. The both waves are synthesized at the hybrid 6, and the band near the resonance frequency of the reflection type multi- stage resonators 12, 12' is picked up at the output terminal 2' and other frequency is reflected at the polarization separator 13 and picked up at the output terminal 2. The system acts like a branching filter as a whole.