Multiwideband Bandpass Filter Based on Folded Quad Cross-Stub Stepped Impedance Resonator

Figure 1

The resonator structure: (a) crossed open stub resonator, (b) quad cross-stub stepped impedance resonator (proposed), (c) folded quad cross-stub stepped impedance resonator (proposed), and (d) comparison of bandwidth of the COS and QC-SSIR structure.

(a)

(b)

(c)

(d)