Compact WLAN notched ultra-wideband band pass filter

Abstract

This paper has investigated WLAN notched Ultra-Wide Band (UWB) Band Pass Filter with a wide upper stop band. The proposed design has folded half-wave line that has been incorporated in between slot line resonators. Designed UWB band pass filter has 3-dB cut-off frequencies at 3.2 GHz and 10.1 GHz with a notched band from 5.1 GHz to 5.4 GHz. Return loss and insertion loss in the first pass band have been greater than 12 dB and less than 1.5 dB. These have been greater than 25 dB and lesser than 1.8 dB in the second pass band. In the upper transition edge, an introduced filter has accomplished pointed roll-off with attenuation of 62 dB, wide stop band with the rejection of 20 dB till 12 GHz, and greater than 17 dB from 12 GHz to 18 GHz. Higher-order harmonics have been suppressed through quarter wavelength open stubs. The overall size of the filter is 27 x 9 x 0.8 mm3.