An Interferometric Characterization Technique for Extreme Impedance Microwave Devices

This paper presents a microwave impedance characterization technique for extreme impedance devices. The method is based on active interferometry and uses a 2-source 4-port vector network analyzer, which allows for a compact and straight-forward implementation. A new calibration algorithm is described that incorporates error terms from two separate three-known-load calibrations. Based on simulated and measured data, the proposed technique shows substantial improvement in obtaining the impedance of two offset-short devices when compared with conventional measurements.