Calibrated measurements of waveforms at internal nodes of MMICs with a LSNA and high impedance probes

Waveforms measurements at internal nodes of MMICs are essentials for the analysis of both operating conditions and reliability aspects. Currently, the large signal network analyser (LSNA) is the most suitable time domain measurement setup. We propose, in this paper to associate the LSNA with high impedance probes (HIPs) and to do a new calibration procedure, in order to perform measurements at internals ports of multi-cells power amplifiers. Our novel measurement setup enables an easy and fast way to get corrected time domain waveforms measurements. The HIP calibration and measurement procedures can be easily added to the original LSNA driver software. Indead, the HIPs are considered like a classical test-set through the software and do not modify the traditional use of LSNA. This work is applicated here to the characterisation of a class F amplifier at S band.