Accession Number : ADD009481

Title :   Directly Modulated Sonobuoy Transmitter Using Surface Acoustic Wave Sensor.

Descriptive Note : Patent

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Junod,Michael T ; Bates,Albert M

Report Date : 09 Feb 1982

Pagination or Media Count : 6

Abstract : Serving as a hydrophone in the lower unit of the sonobuoy, two surface acoustic wave resonators for determining the resonant frequency of two independent oscillators are also used to sense pressure and thus sound. The outputs of the two resonators are mixed and then passed through a low pass filter to provide a low frequency hydrophone output signal and to remove temperature induced signal distortion. A line driver and low cost twin lead transmission line provides the signal to the upper floatation electronic unit of the sonobuoy for conversion to the desired RF carrier frequency. In a single-channel sonobuoy, this signal is multiplied and amplified for transmission to a distant receiver. In a multi-channel sonobuoy, this signal acts as a reference frequency for the frequency synthesizer section of the sonobuoy transmitter. (Author)

Descriptors :   *Patents, *Surface acoustic wave devices, *Sonobuoys, Acoustic resonators, Hydrophones, Low pass filters, Signal processing, Input output models, Multichannel

Subject Categories : Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE