Compact Microstrip UWB Bandpass Filter With Dual Notched Bands Using E-Shaped Resonator

A new microstrip ultra-wideband (UWB) bandpass filter (BPF) with two sharp notches using E-shaped resonator is proposed in this letter. The circuit topology and its corresponding electrical parameters of the initial microstrip UWB BPF are achieved by a variation of genetic algorithm (GA). Then, the resonance properties of the E-shaped resonator are studied. Results reveal that the multiple-mode property of the E-shaped resonator can be utilized in the UWB BPF design to achieve dual band-notched performance. To validate the design concept, a microstrip UWB BPF with two notched bands respectively centered at frequencies of 5.9 GHz and 8.0 GHz is designed and fabricated. Both simulation and experimental results are provided with good agreement.