A new experimental technique using six-port reflectometers, operated in reverse configuration, suitable for sourcepull device characterization is reported. Analytical analysis and experimental verification show that using the six-port in reverse configuration allows the impedance of the test port of the sixport junction to be measured. This measurement technique is suitable for the design of low noise amplifiers and of active nonlinear circuits such as FET mixers and power amplifiers. This measurement technique has been used for the first time to study: 1) The effect of the LO and RF impedances of the input matching circuit of a MESFET gate mixer on the IF output power and conversion gain. 2) The effect of the phase of a LO offset short circuit presented to the MESFET output on the DC power efficiency and the conversion gain of the gate mixer.Experimental results of a NE-72084 GaAs MESFET gate mixer demonstrate that by presenting to the MESFET the optimum input RF and LO impedances and the right phase for the LO offset short-circuit at the output, 2.5 dB conversion gain can be achieved with a 2.5 times reduction of DC power consumption as compared to conventional design approaches.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.