Ultra-broadband six-port reflectometer

In this paper the design of an ultra-broadband six-port reflectometer, operating in an over-decade frequency range is presented. The proposed modifications of the classic solution have allowed to significantly increase the operational bandwidth and to ensure the stability of the reflectometer performance in terms of frequency. Moreover, an improvement allowing to eliminate the seventh, unused port has been proposed. The presented six-port reflectometer has been experimentally verified by reflection coefficient measurements of several reflective elements in a frequency range from 0.5 to 5.5 GHz, showing a very good agreement with the results obtained using commercial VNA.