Surface acoustic wave unit

Abstract

Abstract PURPOSE: To obtain the surface acoustic device which can detect the information apart from a space suitably, by using the surface acoustic wave element providing at least a pair of surface acoustic wave electrodes and the antenna in common use for transmission and reception as the terminal unit for transmitting information. CONSTITUTION: The electromagnetic waves received from the antenna 5 are converted into surface acoustic waves with the transducers 3a and 3b and propagate toward the arrows A and B on the piezoelectric substrate 2 as shown in Figure. The surface acoustic waves excited after the propagation time of the surface waves between the both are again converted into electric signal and retransmitted from the antenna 5 to air. This unit is used as temperature sensor and used as the terminal unit 6 at the transmission side for information. The fixed station 7 apart from a space opposing to this is provided and RF pulse is transmitted from the antenna 8. Since the RF pulse is returned from the terminal unit 6, it is again received at the fixed station 7 and by measuring the time difference τ between the transmission and reception RF pulse, the temperature providing the terminal unit 6 can be measured. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Riichi Kodama

Bibliographic Details