A new calibration method for the measurement of a multiport microwave tomography system with a 2-port vector network analyzer

A new method for the calibration of a multiport microwave tomography (MWT) system measured with a 2-port vector network analyzer (VNA) is presented. The two VNA ports are mapped to the eight input ports of the MWT system by means of a switching network. This contribution deals with the calibration of the switching matrix. In consideration of the application, the proposed approach reduces the mechanical complexity of the calibration procedure significantly, by eliminating transmission connections between nonadjacent ports. This enables a simplified automation of the measurement setup. In addition, every step of the calibration procedure utilizes self-calibration techniques. Thereby, increasing the diversity of the procedure. Furthermore, the proposed method reduces the number of measurements required for the calibration in relation to comparable methods.