Six-port reflectometer realization using two microstrip three-section couplers

Abstract

The single-section couplers are narrow band devices, so in order to broaden the useful bandwidth, three-section couplers are used. In this paper a system of two of three-section couplers is used to construct a six-port reflectometer. The realized six-port reflectometer is calibrated and used to measure different unknown complex terminations. The results of the six-port reflectometer is found to be in good agreement with the measurements of the vector network analyzer (HP-8510C) with an error not exceeding 4% in magnitude and 4/spl deg/ in phase in the frequency range (2.4-4.4 GHz).