Modelling and measurement of picosecond transients on nonlinear transmission lines

A time-domain model for the formation of picosecond voltage transients on a Nonlinear Transmission Line is presented. Physics-based models for varactors and coplanar lines are used for the numerical calculations. The varactor model is validated by measuring the voltage shape reflected from a single varactor. The modelling results for the output voltage of a Nonlinear Transmission Line are compared with electro-optical measurements and with on-wafer sampling circuit measurements. The measured waveforms are in excellent agreement with the model calculations.