A compact dual-band bandpass filter implemented with an embedded coplanar waveguide (ECPW) resonator and a capacitively loaded resonator (CLR) in substrate integrated waveguide (SIW) cavity is presented and analyzed in this paper. Three transmission zeroes (TZs), of which two are located in the middle of the two passbands and one located in the upper stopband, are obtained to improve the inner-band isolation and the selectivity of the filter. The center frequencies and bandwidths of the two passbands can be easily tuned by changing the geometrical parameters of the two resonators. The proposed dual-band SIW filter is demonstrated with center frequencies located at 8.41/14.29 GHz. The measured insertion loss is -1.28/-1.91 dB with the corresponding fractional bandwidth (FBW) of 21.2%/7.3%. The measured results are in good agreement with the simulated ones.
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