Accession Number : ADD011054

Title :   Underwater Depth Telemetry,

Descriptive Note : Patent,


Personal Author(s) : Verburgt,P W

Report Date : 24 Jan 1984

Pagination or Media Count : 8

Abstract : An acoustic telemetry system and technique are disclosed for remotely measuring the underwater depth and descent rate of hydrographic package. Analog signals indicative of hydrostatic pressure exerted on the package and related to its underwater depth are periodically sampled and converted to an N-bit digital word representative of the value of pressure. Each bit of the digital word operates one a of a plurality of tone generators of different acoustic frequencies in a narrow band, and the outputs of the tone generators are combined with a reference tone continuously generated to permit resolution of Doppler shifts. Acoustically projected through the water to a remote hydrophone, a composite signal representative of the combined tones is corrected for Doppler shifts by translating the frequency of the signal in accordance with shifts detected in the reference tone. The composite signal is digitally decoded to reproduce the N-bit digital word using a parallel series of frequency detectors each tuned to one of the narrow band acoustics frequencies, and the word is displayed as an indication of underwater depth using a series of latches to ensure a steady data display. (Author)

Descriptors :   *Patents, *Telemeter systems, *Underwater communications, *Doppler systems, Data displays, Audio frequency, Steady state, Hydrostatic pressure, Underwater, Analog signals, Digital systems, Doppler effect, Audio tones, Narrowband, Depth, Acoustic equipment, Rates, Words(Language), Descent, Frequency, Generators, Value, Signals, Resolution, Pressure, Water

Subject Categories : Telemetry
      Non-radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE