A new design of a miniature microstrip resonator with interdigital structure

A microstrip resonator with a new design based on an interdigital structure has been studied, which is distinguished by its high degree of miniaturization. It is shown that the resonator length can be considerably decreased at a significant increase in the figure of merit (Q factor), provided that the number of microstrip conductors in the interdigital structure is increased without changing gaps between them. A prototype of the resonator manufactured on a ceramic substrate with dielectric permittivity $\varepsilon$ = 80 has a resonance frequency of 817 MHz and Q = 100 for microstrip structure contour dimensions of 1 $\times$ 5.5 mm. It is shown theoretically and confirmed experimentally that the Q factor of the proposed resonator is higher than those of well-known microstrip analogs under otherwise equal conditions.