On-line waveform monitoring system for the design and characterization of MIMO RF PAs

A measurement system capable of relative waveform measurement and on-wafer power de-embedding is presented in this paper. A comprehensive description and calibration mechanism of the developed measurement system is reported. The calibration methodology has been implemented on a two-port Microwave Transition Analyzer (MTA) but is readily applicable to multiport receiver system. The calibration strategy is based on reflection measurement using open-short-load (OSL) calibration standards at each port of the measurement system. The proposed calibration algorithm is fast, simple and accurate for power de-embedding and waveform monitoring. This kind of on-wafer power de-embedding and waveform monitoring is helpful in the design of switching mode power amplifiers (PAs). Finally, the relative waveform measurement of a 3W GaAs FET demonstrates that the developed system is capable of accurately monitoring the input and output ports of multiport microwave devices.