A novel compact multilayer wideband bandpass filter with lumped elements

A novel compact, multilayer wideband bandpass filter (BPF) with lumped elements is presented in this paper. It is realized by cascading a high pass filter (HPF) and a low pass filter (LPF). Two finite transmission zeros are added to achieve a sharp out-of-band roll-off skirts. Quasi-lumped elements and the multilayer structure are employed to miniaturize the filter´s size. The filter is analyzed by using equivalent circuit model and full-wave electromagnetic simulation first. Good agreement between equivalent circuit model, full-wave simulated and measured responses of proposed filter is demonstrated. and validated its operation principle. Then, its performance is experimentally verified and a wide 3dB bandwidth from 1.1-2.7GHz and a 15dB-rejection stopband can be obtained.