A Novel Compact Dual-Mode Filter Using Cross-Slotted Patch Resonator for Dual-Band Applications

A novel dual-mode BPF using cross-slotted patch resonator (CSPR) combined with a square etched slot to have dual-band performances is proposed and developed for hybrid and monolithic microwave and millimeter-wave integrated-circuit. Pair of unequal crossed slot is embedded in the center of λ/4 patch resonator to generate a passband. When the widths of the crossed slots are different, the slots are as the perturbation element to generate two transmission zeros. Meanwhile, a square slot is introduced and tilted at the angle of 45° within the center of the CSPR to tune the second resonant frequency over a wide frequency range for application in 2.4/5.2 GHz response. The measured result is in good agreement with the full-wave simulation result.