An ultra-wideband (UWB) bandpass filter (BPF) with hybrid coplanar waveguide (CPW)/microstrip structure is introduced in this paper. Then a pair of lowpass filters is integrated on the CPW feed lines to achieve a good out-of-band rejection. At last, a notched band with two transmission zeros is realized at 5.8 GHz by using a symmetric E-shaped slot-line and etching slots on microstrip resonator. Two transmission zeros are realized in the desired notched band, and out-of band rejection is more than 32 dB. In order to prove the validity, the proposed filter is fabricated and measured, and the measured results are in good agreement with simulated ones.
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