Multitone load-pull characterization system for power and distortion analysis of microwave transistors

This paper presents a new load-pull measurement system for transistor characterization under N tone excitation signal where N/spl ges/2. The new set up uses an arbitrary wave generator (AWG) to generate the spectrum of any N desired tones to be applied to the transistor and a microwave transition analyzer (MTA) as a receiver. With such system, constant output power contours and intermodulation rejection (IMR) contours in the /spl Gamma//sub L/(fo) plane can be obtained. Using such system, one can experimentally investigate intermodulation distortion in transistors as function of their loading and the number of tones.