Tapped-Line Interdigital Bandpass Filters with Narrow Bandwidth Using Asymmetric Broadside Coupled Coplanar Waveguides

We present the newly developed bandpass filters (BPFs) using the asymmetric broad-side coupled coplanar waveguides (ABC-CPWs). These CPW-BPFs are made of the interdigital arrays of the resonators and the tapped-line to-the resonators. The experimental results are given of the newly developed interdigital BPFs using ABC-CPWs and compared with the simulations to check the passband characteristics and the spurious resonance responses. We developed that the interdigital BPFs using the ABC-CPWs have very small fractional bandwidth. The newly developed interdigital BPFs using the ABC-CPWs have some advantages such as compact size, lighter weight, low insertion losses and very small fractional bandwidth. The good agreements are obtained between them.