Calibrated broadband measurement technique for complex permittivity and permeability

A technique to measure the complex permittivity and permeability using two different types of calibration is presented in this article. The technique is based on a classical transmission-line analysis, implemented on a strip-line structure. A new calibration technique, namely object-reflect-line (ORL), is proposed to meet the challenge of an extremely low reflection line for accurate measurement. In the proposed calibration, the thru standard of conventional thru-reflect-line (TRL) is replaced by a standard with a known object. Since the ORL calibration uses only a single device, it reduces the fabrication cost, the measurement complexity, and the potential error in the thru measurement needed in the TRL method, which uses an additional device. The analysis is extended with consideration of the impact on material loss in measurement accuracy. The simulated and measured results with a variety of nonmagnetic and magnetic materials demonstrate the effectiveness of the proposed method over broadband microwave frequencies.