Monolithic implementation of air-filled rectangular coaxial line

Abstract

An air-filled rectangular coaxial line has been monolithically fabricated. Coaxial line is a suitable structure for reducing the coupling between two dose transmission lines. Over the measurement range (from 4 to 38GHz), the fabricated coaxial line has very low attenuation (< 0.08dB/mm) and low return loss (< -33dB). The isolation between the two dose lines separated by 40 mu m is below -43dB with 1mm coupling length.