Convolution and Correlation Using Nonlinear Interactions of Lamb Waves

Excitation of Lamb waves in several of the lower order modes has been demonstrated on polarized plates of PZT using interdigital transducers. It is shown that these waves cannot only be used in dispersive delay lines, but also that convolution and correlation can be efficiently performed using the nonlinear interaction between acoustic plate waves propagating in the same or different modes. The fact that plate modes exist with a broad range of velocities while they maintain the accessibility and high energy density of surface waves enables these devices to combine the advantages of pre- vious bulk and surface wave methods.