An ultra-wideband bandpass filter using multi stub resonator with notch band functionality

In this paper, a new method of forming an UWB BPF with notch band functionality has been presented. The design uses a multi stub loaded resonator on a Uniform Impedance Resonator (UIR) to form an Ultra Wideband (UWB) range and a rectangular spiral resonator to form a notch band at 5.55 GHz to avoid interference from existing narrow band radio signals. The passband insertion loss is within 0.5 dB. The filter exhibits a wide stop band till 15 GHz. Presence of a proper UWB range along with notch band and stop band characteristics are the ideal characteristics.