Microstrip U-shaped resonators
DOI:
https://doi.org/10.3103/S0735272712080043Keywords:
U-shape resonator, hairpin resonator, left and right arms, resonant frequency, resonant electrical length, unloaded qualityAbstract
Influence analysis of U-shaped microstrip resonators’ parameters and parameters of dielectric substrate on resonant frequencies and unloaded quality-factor of resonators is conducted. Three kinds of U-shaped resonators are considered which differ in operation modes at the resonator’s ends: short-circuit or no-load. It is revealed that in cases of small spacing between the arms of U-shaped resonators distribution of their resonant frequencies significantly differs from the corresponding quarter-wavelength or half-wavelength resonators and leads to decreased stop-band in pass-band filters based on them. Experimental research shows that decreasing the spacing between the arms of U-shaped resonators leads to decrease in quality-factor by 20–30%. Experimental samples were manufactured on substrates with εr = 92 and εr = 38.
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