Dual-mode elliptic-function triangular-patch bandpass filters using capacitive-coupling slot technique

A new triangular-patch bandpass filter (BPF) using a pair of V-shape slots is presented in this paper. The pair of the V-shape slots can provide capacitive coupling which produces a dual-mode elliptic-function response. A theoretical analysis of capacitive-coupling characteristics of the dual-mode BPF with different slot dimensions is presented. Also, a set of simple equations is developed to determine the dimensions of the triangular-patch resonator based on the resonant frequency, F₀. Finally, measured results are given which demonstrate the validity of the proposed design method.