Weighted SAW reflector using distributed acoustic reflective dots

摘要

A reflective grating (18) having spaced grid lines (36) patterned on a piezoelectric substrate (12) for controlling the magnitude and phase of surface acoustic waves (28) in a reflective filter (10) or resonator. The magnitude and phase of the surface acoustic wave (28) are controlled by a sampling period (34) of the reflective grating (18) and the density and sequence of distributed acoustic reflective dots (42). The reflective dots (42) are randomly distributed within gaps (40) between adjacent grid lines (36) or on top of the grid lines (36) of the reflective grating (18). The pattern of the reflective dots distributed within the gaps (40) or on the grid lines (36) is determined by the dot density, where the dot density varies from a lowest density of 0 to a maximum density of 1.