A vector corrected waveform and load line measurement system for large signal transistor characterisation

A vector corrected large signal measurement setup based on a microwave transition analyser has been developed to enable device output harmonic and waveform measurement with variable drive level, frequency, DC bias and fundamental load impedance. A novel capability of this system is the ability to plot the device dynamic load lines during measurement so that nonlinear effects can be investigated as a function of bias and load impedance in real time. Load line results are shown for a MESFET and an HBT device and the effect of load impedance on device behaviour is described. >