Abstract: A PSK demodulator, by which a first output signal obtained from a local oscillator circuit working asynchronously with respect to the carrier phase of an inputted burst PSK signal and a second output signal shifted in phase by 90.degree. with respect to the first output signal are multiplied by the inputted burst PSK signal by means of a first multiplier and a second multiplier, respectively. Each of the output signals from the first and second multipliers are compared with a first reference voltage and a second reference voltage, which is lower than the first reference voltage. The output signals are classified into 4 sorts of level signals, those which are higher than the first reference voltage and those which are lower than the second voltage; and thus the inputted burst PSK signal is demodulated by using these 4 sorts of level signals.

Abstract: A surface acoustic wave device comprises a silicon substrate, an aluminum nitride layer provided on the silicon substrate, a zinc oxide layer provided on the aluminum nitride layer, and electrodes provided on either the silicon substrate, aluminum nitride layer or zinc oxide layer. Propagation is in the [001]- or [011]-axis direction on (100) Si, [001]- or [110]-axis on (110) Si, [112]-axis on (111) Si, or [111]-axis on (112) Si.

Abstract: A surface acoustic wave device comprises a silicon substrate, a silicon dioxide layer provided on the silicon substrate, a zinc oxide layer provided on the silicon dioxide layer and input and output electrodes provided on the zinc oxide layer. The silicon substrate is cut by a crystalline surface substantially equivalent to the (100)- or (110)-surface, and the zinc oxide layer is such that its crystalline surface substantially equivalent to the (0001)-surface is parallel to the cut-surface of the silicon substrate, so that a surface acoustic wave entered from the input electrode is propagated to the output electrode in a direction substantially equivalent to the [011]- or [001]-axis of the silicon substrate.

Abstract: A surface acoustic wave device comprises a silicon substrate, a conductive layer provided on the silicon substrate, a silicon dioxide layer provided on the conductive layer, input and output electrodes provided on the silicon dioxide layer for input and output of a surface acoustic wave, and a zinc oxide layer provided on the electrodes. The silicon substrate is cut by a crystalline surface substantially equivalent to the (111)-surface, and the zinc oxide layer is such that its crystalline surface substantially equivalent to the (0001)-surface is parallel to the cut-surface of the silicon substrate, so that the surface acoustic wave entered by the input electrode travels to the output electrode in a direction substantially equivalent to the [112]-axis of the silicon substrate.

Abstract: A surface acoustic wave device includes a silicon substrate having a main surface with a given crystalline orientation, a zinc oxide layer deposited on the main surface of the silicon substrate and a dielectric layer as well as electrodes both formed in contact with said zinc oxide layer, so that a surface acoustic wave will be propagated along a given crystalline axis direction of the silicon substrate.

Abstract: A surface elastic wave element comprising a (110)-oriented silicon substrate, a zinc oxide layer formed on the silicon substrate and electrodes formed on the zinc oxide layer so as to propagate surface elastic wave to the [001]-axis direction of the zinc oxide layer.