The Use of a Matched Symmetrical Five-Port Junction to Make Six-Port Measurements

A new configuration for six-port measurements is proposed. It consists of a symmetrical five-port junction and a directional coupler. Assuming the components to be ideal, it is shown that the proposed six-port has optimal properties for accurate determination of complex reflection coefficients. An experimental coaxial five-port junction has been designed and used in a six-port measurement system. After calibration, using five impedance standards, measurements on precision loads indicate good measurement accuracy over the frequency band where the five-port is well matched.