Surface acoustic wave device, and demodulation device and communication system using the same

摘要

A surface acoustic wave device includes a piezoelectric substrate, an input electrode formed on the substrate and an output electrode formed on the substrate. A surface acoustic wave is generated from the input electrode to propagate in a predetermined direction in accordance with an input signal. In the output electrode, a plurality of taps are arranged in a propagation direction of the surface acoustic wave on the substrate. The surface acoustic wave is converted into an electrical signal by the output electrode. The taps of the output electrode are weighted so that signals output from the taps have substantially equal magnitudes.