Compact-size coplanar waveguide bandpass filter

A compact-size coplanar waveguide (CPW) bandpass filter (BPF) is proposed. In this study, we use the bended stub with novel folded skill to improve the three parallel coupled-lines structure of BPF for N = 1. It gets the sharp transition band (TB) and reduces the dimension of the circuit by 66.67% at 2.45 GHz. Its center frequency can be shifted easily by adjusting the interfaces of SS and S'S' simultaneously. It is very useful for applications in the wireless communication systems.