By using a composite coupling structure for coplanar waveguide (CPW)/microstrip, a new dual-band bandpass filter (DBBPF) stacking inverted Y-shaped CPW resonators and rectangular ring resonators is proposed. Two resonant frequency bands are simultaneously excited by the CPW feed line, However, it can be convenient to tune individually. Several transmission zeros are realized to improve the selectivity of the filter and achieve wide stopband rejection. Good agreement between simulated and measured results demonstrates the validity of this DBBPF.
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