Comparison of simulation and measurements of time-domain field-to-line coupling in TEM cell

This paper presents an analysis of time-domain electromagnetic (EM) field coupling to transmission lines on the printed circuit board (PCB). The time-domain 3D EM simulation of the field-to-line coupling is performed using the uniform plane wave excitation defined by broadband Gaussian pulse. The simulated time-domain response obtained at the PCB line ends can be thought of as impulse response of the field-to-line coupling system. Therefore, by convolving the simulated impulse response with the time-domain waveform of the EM field which has limited frequency range, it is possible to predict the voltage induced on the PCB lines. This approach is validated by measurements of the microstrip transmission line inserted in the transverse electromagnetic mode (TEM) cell connected to the step signal generator. The coupling of the TEM cell EM field and MS line generates the voltage signal which is measured at the line ends. The measurements are compared to the models developed by 3D EM simulator and very good agreement is obtained.