A compact ultra-wideband (UWB) bandpass filter (BPF) with simultaneous narrow notched band and out-of-band performance improvement is presented. The UWB BPF is built up using the hybrid microstrip and coplanar waveguide (CPW) structure. By employing split-ring resonator (SRR) defected on the lower plane, the narrow notched band was introduced. The center and bandwidth of the notched band can be controlled by adjusting the length and width of the SRRs. A novel cross-shape patch is constructed to implement transmission zeros in the upper out-of-band so as to suppress the spurious passband. The measured results show that insertion loss is less than 1.7 dB, the return loss is more than 13 dB and the variation of group delay is less than 0.2 ns. Furthermore, the width of narrow notched band is about 0.15 GHz and the attenuation is more than 18 dB at the center frequency of 5.76 GHz. The upper stopband is up to 15.2 GHz with rejection greater than 20 dB.
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