Propagation of Interferences in Asymmetric Strip Structures with Modal Decomposition

The paper evaluates the possibility of using analytical models to calculate the time response of asymmetric strip devices with modal decomposition to typical waveforms of interference: ultrashort pulse, damped sine and sinusoid with Gaussian modulation. To compare the analytical results, the strip devices were simulated using different approaches in different software products. As a result, the responses obtained analytically completely coincided with quasi-static simulation responses. This happened in all cases except those when the faster (in terms of propagation velocity) components of the response came to the output of the device and were superimposed on the slower ones. This can be explained by the influence of reflections and long duration of excitation. Pulse reflections were not taken into account in the calculation model of the response, which is its limitation. It was revealed that the results of analytical and electrodynamic calculation of the response may differ by 3.7–38% in amplitude and 1.5–2% in delay. The totality of the results obtained in the work confirms that analytical models can be applied to preliminarily calculate the response of strip devices with modal decomposition. Moreover, the accuracy of response calculation can be high.