Extreme Low Frequency Hydrophone

Extreme Low Frequency Hydrophone (LAR-TOPS-321)
Senses and isolates infrasound down to .0001 Hz while submerged
The Extreme low frequency infrasonic hydrophone, with the associated software, is capable of sensing down to .0001 Hz, a 4.999 Hz improvement from current similar systems. This ultra-low power consuming hydrophone also isolates and removes significant amounts of background noise, inherent to the electret type microphone not previously introduced into hydrophone applications. The uniquely robust unit design also permits for sub-freezing operations deep below the surface. The results promise to drastically alter lives and multiple industries, enabling totally new data for weather monitoring and earthquake/tsunami prediction among numerous other academic applications. It could also improve current hydrophone accuracy or reliability in finding oil resources, and will enable monitoring human generated infrasound in water.

The Technology
The extreme low frequency hydrophone boasts unprecedented capability for precise detection as proven in testing, where it sensed wave range between surface waves and tidal surges with periods between .3 and 30 seconds, or 3 to .033 Hz. The technology uses a back-electret microphone, inherently reducing noise, in a stainless steel body. The stainless steel diaphragm conducts infrasound well and the materials robust nature and internal configuration facilitates sub-freezing and deeply submerged sensing of sound down to .0001 Hz. With an appropriately spaced array of three hydrophones it is possible to determine the direction of origin of a submerged infrasonic source, the addition of one more in another location will also enable determination of the precise location of origin. The oil industry uses existing infrasound systems to locate undersea oil deposits and this technology could potentially improve the accuracy or reliability of current practices. It could also be used to give tsunami and earthquake warnings, monitor ships, and to generate electrical energy from infrasound. This technology has potential to unlock new industry uses not currently understood due to the unprecedented nature of its capabilities.
buoy Image of prototype hydrophone. Image Credit: NASA
  • Frequency range from .0001 Hz up to 100 Hz detection range
  • Electret based design eliminates more background noise than other hydrophones
  • Can be used in high pressure marine environments
  • Can be used to detect infrasound below freezing temperatures
  • Low power consumption

  • Offshore oil industry
  • Weather monitoring (earthquake, tsunami and tidal)
  • Monitoring wind-generated gravity waves on the free surface of the bodies of water
  • Monitoring of man-made infrasonic sources such as boats
  • Piezoelectric design allows for energy harvesting from full detection range
Technology Details

LAR-19681-1 LAR-19059-1
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