A Uniform Coupled-Line Dual-Band Filter With Different Bandwidths

This letter presents a planar dual-band bandpass filter (BPF) of adjustable bandwidths. The proposed method of simultaneously designing the J-inverters and the resonators enables a BPF to have bandwidth control, without any structural modification to the uniform coupled lines loaded with shunt stubs. A systematic design approach is introduced along with experimental results that verify the proposed method.