Time domain analysis of nonlinear harmonic response generated in RF-SAW resonator

Time domain analysis of the nonlinear second-order harmonic response generated in the RF-SAW resonator is discussed. At first, how to pick up the very weak complex amplitude, which consists of the magnitude and phase, from the SAW resonators, is demonstrated. Then, the time domain response is calculated by the inverse Fourier transform of the complex amplitude in the frequency domain. It is confirmed that the time domain response consists of a few components with different delay times. Two components are extracted individually by the time-gating technique and transformed into the frequency responses. The results support the prediction about the generation mechanism of the second-order harmonic response in the SAW resonator. Thus, it is verified that the time domain analysis should be a powerful tool for understanding the nonlinearity of SAW devices.