A new baseband measurement system for characterization of memory effects in nonlinear microwave devices

This paper presents a new measurement setup for characterization of memory effects in microwave devices. The proposed setup extends the standard LSNA to capture the baseband spectrum from DC up to 100 MHz. This enables characterizations of memory effects in nonlinear microwave devices when using wideband modulated signals as stimuli. The extension of the baseband spectrum down to DC is very important when characterizing slow memory effects, such as self-heating and trapping. The importance of this extension is illustrated by two-tone measurements and simulations on a GaN device to show the effects of the dynamics in the thermal impedance