The M20 Particle Motion Sensor Bottom-Mounted System (also known as a Particle Velocity Sensor) is designed to measure 3-D particle motion and acoustic pressure in a broad range of environments – from within 1 metre of an air gun, to quiet ocean environments – in an easily-transportable package.
The heart of the system is the M20 hydrophone which includes a gyro-stabilized 3-dimensional orientation sensor, 3 dipole sensors and one omnidirectional acoustic pressure sensor.
Gain is factory set to optimise to the users requirements and in-band resonance can be adjusted to better support specific requirements. Bearing accuracy < 2 degrees relative to magnetic north.
The M20 Bottom Frame is a lightweight deployment apparatus specifically designed to accommodate the M20 hydrophone and a variety of support instruments. The stainless steel frame provides a sturdy, stable mounting solution for the M20, effectively de-coupling it from environmental vibration. The bolted frame and easily-detachable M20 sensor provide for convenient transport if space is at a premium.
Additional support on mounting, deploying, etc. can also be provided.
The illustration to the left shows a typical installation for the M20 Bottom-Mount System, deployed in an easy-to-access shallow water location while an off-shore vessel provides the necessary low-pressure sound source.
GeoSpectrum SoundView™ Post Processing Software
The M20-110 System is supplied with post-processing software. SoundViewTM is a spectral processing and display application that includes omnidirectional and vector-sensor processing. SoundViewTM also has the ability to process real and complex heterodyned time-series data. SoundViewTM is a commercialized version of a sonar processing application originally developed for defense research.
SoundViewTM is compatible with Windows x64, Linux x64, and OSX. Only one version is supplied with each license ordered.
The illustration to the left is showing direction of arrival for acoustic signals. Different bearings are indicated by different hues.
|Useful frequency range||1 Hz to 3,000 Hz|
|Operating and survival depths||300 m|
|Operating and storage temperatures||-40 to +70 °C|
|Size||127 mm diameter, 165 mm length|
|Sensitivity||As required, see chart below for band shape on PV sensors, Omni is flat, typical response -180 dB re 1 μPa|
The graph to the left shows Nominal Response in the X, Y and Z Axes of Receive Sensitivity vs. Frequency.
Download the Particle Motion Sensor (M20-110) Brochure [UPDATED]
Download the Particle Motion Sensor Standalone Sensor (M20-100) Specification Sheet
Download the M20-040 Hydrophone Specification Sheet
Download the M20-020 Hydrophone Specification Sheet
Contact GeoSpectrum Technologies for more information. To find out information on other GTI hydrophones, visit the Hydrophones page.
Click here to view a paper written by Dr. Bruce Armstrong and Paul Yeatman, co-founders of GeoSpectrum. This paper was published by Proceedings of the Institute of Acoustics.