High-Quality STW Resonators: Calculation Methods and Application in Self-Oscillators

Abstract— The results of the development of high-quality resonators based on surface transverse waves (STW) are reported. It is shown that the use of contemporary computational packages (COMSOL Multiphysics), as well as the improvement and development of already known calculation methods (modified model of coupled modes), make it possible to efficiently and quickly perform the calculation of STW devices. The results of comparing the theoretical and experimental characteristics of the transmission coefficient of a two-port STW resonator are presented. It is demonstrated that, using optical lithography, it is possible to manufacture high-quality resonators at frequencies of 0.5–2.5 GHz. Typical values for the unloaded Q-factor of 500-MHz resonators are 27 000–29 000. The results of measurements for a two-port STW resonator included into a 500-MHz low-noise self-oscillator model are reported to demonstrate phase noise at a level of –148.7 and –183.5 dBn/Hz at an offset of 1 kHz and 1 MHz, respectively, from the carrier frequency and a jitter of 2.8 fs. The self-oscillators based on STW resonators with a low level of phase noise and a small jitter can be demanded in the areas where it is critically necessary to provide a maximum dynamic range of digital signal processing ducts.