Simple method for correction of reflection values by means of coaxial quarter wavelength air line impedance standards

Empty SIW Technologies: A Major Step Toward Realizing Low-Cost and Low-Loss Microwave Circuits

“…In these coaxial lines, the substrate was removed in order to obtain components with accurate and predictable electromagnetic properties that could be used as impedance standards due to the small differences between the measured line characteristics and their analytical properties. Since the publication of these first articles, others studies related to air-filled coaxial lines were proposed in [63]- [67] . For instance, air-filled coaxial cables have been employed to achieve immittance transformation, skin-effect corrections, as well as feed networks, just to cite a few examples among many other devices and/or applications.…”