Design of a compact microwave six-port vector voltmeter for UWB applications

This paper presents the design of a compact and ultra wideband (UWB) planar six-port vector voltmeter. By performing only scalar power measurements, the proposed device is capable of determining the ratio of two complex voltages or two complex wave amplitudes over an ultra wide frequency band of 3.1 to 10.6 GHz. The vector voltmeter is formed by an assembly of three quadrature couplers and one out-of-phase power divider in multi-layer microstrip/slotline technology. Its UWB operation is confirmed by simulations and measurements