CONVOLUTION AND TIME INVERSION USING PARAMETRIC INTERACTIONS OF ACOUSTIC SURFACE WAVES

We report on the observation of acoustic convolution, time inversion, and electronically variable delay in real time using 105‐ and 220‐MHz surface acoustic waves in YZ‐cut LiNbO3 delay rods. The time inversion is a special case of correlation, where a short ``pip'' pulse will create a reflection in time for the injected input signal pulse. The conversion losses in the processing were 64–74 dB.