Key Features

Incorporates Sonardyne's 6G® Technology

Incorporates Sonardyne's Wideband 2® signal Technology

Autonomous sensor logging combined with high speed acoustic telemetry of recorded data

Freefall deployment from surface vessel

Integrated acoustic release for buoyant ascent to the surface

Long life – up to 5 years with excellent corrosion resistance

Flexible 100 to 6000 bits per second Wideband 2 acoustic telemetry modem link

Wireless configuration using surface software and acoustic dunker

The Pressure Inverted Echo Sounder (PIES) is a long-life sensor logging node that accurately measures the average sound velocity through a column of water from the seabed to the sea surface.

It works by transmitting a wideband acoustic pulse from its stable location on the seabed. This pulse is reflected off the sea surface and returns to the seabed where it is detected by PIES. The resulting data enable two way travel time to be calculated.

At the same time, an accurate measurement of depth (distance to the surface) is made using a highly accurate internal pressure sensor.

Average water column velocity can then be calculated directly from the depth and travel time data, noting that speed = distance x time.

The sampling interval of PIES can be configured serially before deployment and also via its internal acoustic telemetry link. This telemetry link also allows recorded data to be transmitted to surface at data rates ranging from 100 to 6,000 bits per second.

PIES can be free fall deployed to the seabed where it will land in an upright position. When the mission is complete, its integrated acoustic release enables it to be commanded to disconnect from its tripod stand and return to the surface under its own buoyancy ready for collection by surface vessel.

A high capacity primary lithium battery pack enables deployment for months or even years depending on the transmission sampling interval configured.

PIES is compatible with Sonardyne’s LMF Ultra-Short-Baseline (USBL) systems for positioning during deployment and recovery.