A microstrip based Ultra-Wideband (UWB) Bandpass Filter (BPF) with a notch at WLAN and simultaneously improved stopband till 18 GHz is proposed. Meander shaped Defected Ground Structures (DGS) are used to implement the notch (which can be increased in width and number) within the passband and double U-shaped DGS present under the input and output feeding lines are used to attain the suppressed stopband. Experimental results are in good agreement with the simulated data.
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