Design of compact dual-mode open-loop microstrip filter

This paper presents the design of two compact dual-mode open-loop microstrip filters, and their comparisons are described. In design, the dual-mode resonator is used as a doubly tuned resonant circuit, so the dimension of filter is reduced by half and compact configuration is achieved. The dimension of fabricated filter is 1.84 cm*1.84 cm on substrate with dielectric constant of 10. The measured results of filter show good agreement with the theoretical results.