Miniaturization of ultra-wide band-pass filter with multiple notches

Abstract

As the ultra-wideband system (3.1GHz to 10.6GHz) is known to be easily interfered by narrow- band signals laying on the same frequency range, A compact ultra-wideband (UWB) band-pass filter (BPF) with multiple notches is presented in this work. The UWB -BP filter rejects two WLAN bands at 5.2GHz and 5.8GHz in addition to 7.2GHz for C band satellite signals when needed, due to the tuning ability property of the design. It consists of a modified dumbbell DGS unit with a feed line terminated by two H shapes to achieve the UWB band-pass characteristics. Next, two pairs of split ring resonators and a rectangular loop are added to create the WLAN and C band rejection respectively at a level higher than -17dB.

The proposed filter occupies an area of 30× 15????2. To confirm the theory a prototype is fabricated and its measured response is found to be in close agreement with the simulated response.