01525078796 IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS, VOL. 15, NO. 11, NOVEMBER 2005 Ultra-Wideband (UWB) Bandpass Filters Using Multiple-Mode Resonator Lei Zhu, Senior Member, IEEE, Sheng Sun, Student Member, IEEE, and Wolfgang Menzel, Fellow, IEEE Abstract―A novel microstrip-line ultra-wideband (UWB) bandpass lter is proposed and implemented using a multiple-mode resonator (MMR), aiming at transmitting the signals in the whole UWB passband of 3.1……