Analyzing an UWB Bandpass Filter for High Power Applications Using Rectangular Coaxial Cables with Square Inner Conductors

Nasreddine Benahmed, Nadia Benabdallah, Salima Seghier, Fethi Tarik Bendimerad, Boumedienne Benyoucef
DOI: 10.4236/cs.2011.23018                

Abstract

Using the finite element method (FEM) in two dimensions and the CST MICROWAVE STUDIO^® (CST MWS) Transient Solver, the electromagnetic (EM) analysis and the design of a novel compact ultra wideband (UWB) bandpass filter using rectangular coaxial cables with square inner conductors, convenient for high power applications, are presented. The design of the UWB BP filter is based on the use of impedance steps and coupled-line sections. The center frequency around 6.85 GHz was selected, the bandwidth is between 3-10 GHz, the insertion-loss amounts to around 0.35 dB and the return loss is found higher than 10 dB in a large frequency range (4-9.5) GHz. The simulated results of stopband performances are better than 15 dB for a frequency range up to 11 GHz. For the selected center frequency and on a substrate with a dielectric constant of 2.03, the rectangular coaxial cables BPF with square inner conductors is only 6.7 × 8.9 × 33.4 mm in size.

Keywords

Rectangular Coaxial Cables, Square Inner Conductors, Ultra Wideband Bandpass Filter, Compact Filter, Electromagnetic Parameters, Analysis and Design, FEM Method, CST MWS Transient Solver

Conflicts of Interest

The authors declare no conflicts of interest.

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