Electromechanical band-pass filter with cylindrical resonators - has half wavelength resonators with quarter wavelength coupling elements and coupling bridge

摘要

The resonator axes are parallel and are arranged in two parallel planes. Two resonators carry transducers connected to input and output terminals. Coupling elements are provided between adjacent resonators, and at least one coupling bridge is provided between non-adjacent resonators. The length of longitudinally oscillating resonators is equal to half the wavelength at the pass-band centre frequency. Coupling elements carrying out flexural oscillations have a length of a quarter wavelength at the centre frequency. Bridges also carrying out flexural oscillations.