Asynchronous High Quality Factor STW-Resonators with Sectioned Reflectors and Gradually Increasing Period of the Electrodes

This paper presents the calculated and measured data for the influence a sectionalization of the reflectors with electrodes aperiodicity on the quality factor of the asynchronous 1-port surface transverse waves (STW) resonators. Asynchronous topology of the STW-resonator is make by the specified ratio between the electrode period in the IDT and reflectors. The topology optimization of the STW-resonators with sectioned reflectors was provided with a computer calculation using the mixed matrix method. It was shown that use of the sectional reflectors with gradually increasing periodicity results to increasing the quality factor up to 11500 for asynchronous 700-800 MHz STW-resonators on 36°YX90° cut quartz.