A Sampling Oscilloscope Based System with Active RF/IF Load-pull for Multi-Tone Non-linear Device Characterization

This paper presents a fully automated measurement system based around a Tektronix sampling oscilloscope. The system is capable of measuring calibrated time domain voltage and current waveforms at the device plane. A novel active load-pull loop is incorporated which has proved very useful for increasing the speed of multi-tone device characterization, moreover the architecture opens up the possibility of multi-tone load pull measurements, novel concepts are discussed which explain how the system can be used to perform non-linear device characterization in real time, the system also incorporates an intermediate frequency (IF) test set to measure the complete waveforms, which could be useful in characterization of memory effects. Triggering issues of sampling oscilloscopes are discussed in some detail along with a novel sampling approach which allows for more efficient measurement of multi-tone waveforms. Some interesting applications of the system are also introduced.