1997 Volume 18 Issue 5 Pages 261-266
A method of realizing an amplitude-phase modulation using a travelling type ultrasonic device is described. A shear horizontal (SH) plate-mode wave device is composed of four interdigital transducers (IDTs). The first and the forth IDTs are used for the carrier signal input, and device output. The another two IDTs located at the central part of the SH-wave device are used as an attenuator and a phase-shifter for amplitude and phase modulation, respectively. The operation principle that is analyzed with the equivalent circuit model for the amplitude-phase modulator, is given with experimental confirmation. At the frequency of 1.20MHz, the device performs as amplitude modulator and phase modulator, simultaneously.