Accurate sound velocity measurement in sea water

Edited by the Processingtalk editorial team Apr 11, 2003

The new Modus SVS sound velocity sensor uses "time of flight" measurement techniques, and is able to resolve sound speed measurement to 0.001m/s, with stability and accuracy of +/-0.03m/s rms

The latest digital signal processing techniques from Valeport have increased marine sound velocity sensor measurement accuracy ten-fold.

The new Modus SVS sensor uses "time of flight" measurement techniques, and is able to resolve sound speed measurement to 0.001m/s, with stability and accuracy of +/-0.03m/s rms, an accuracy an order of magnitude better than any conventional speed of sound or salinity measurement sensor on the market.

The Modus SVS is available with an acetal housing, for use at depths of up to 1000 metres, on dredging or seismic operations and echo sounder calibration.

For deeper applications, including Swath sonar calibration and ROVs, a titanium bodied sensor is available.

Data output format is operator selectable, using a simple Windows based programme, from RS232, 422 or 485, and in "emulation mode", the Modus SVS can mimic the output format of other designs of sensor, to allow simple retrofit and interfacing to existing systems.

With the addition of an optional pressure sensor, the Modus SVS unit can transmit depth triggered data: other modes include data on demand at up to 8Hz maximum, or one sample per day of burst data.

The Modus SVS is just one of the new Valeport range of Modus sensors - a range of one and two marine sensor instruments designed for "Plug and play" type interfacing to existing loggers, ROV systems, and other instrument packages.