Novel experimental determination of differential amplifier noise parameters

This papers reports for the first time on the measurement of the noise parameters of an active noisy 4-port network. The measurement stems from a novel analytical approach that allows the noise parameters of a noisy linear network with any number of ports to be determined. The analytical approach has been described in a previous publication and passive networks were used to confirm its correctness. This paper applies the new technique to an active 4-port device for the first time. The results confirm the feasibility of measuring active mixed-mode circuits without the use of additional networks such as baluns and open up the possibility of determining mixed-mode noise figure values with the correct terminations at all ports.