With the Nortek AWAC, you get a current profiler and a wave directional system in one unit. You can measure the current speed and direction in 1-m thick layers from the bottom to the surface and you can measure long waves, storm waves, short wind waves, or transient waves generated by local ship traffic.

The 1MHz AWAC is designed as a coastal monitoring system. It is small, rugged, and suitable for multi-year operation in tough environments. It can be operated online or in stand-alone mode with an internal recorder and batteries.

The sensor is usually mounted in a frame on the bottom, protected from the harsh weather and passing ship traffic.

The mechanical design is all plastic and titanium to avoid corrosion. Online systems can be delivered with protected cables, interface units on shore, and backup batteries and recorder. In stand-alone use, the raw data are stored to the internal data logger and power comes from an external battery packs. A variety of options are available with maximum deployment lengths of 4 months with hourly wave data or 8 months when using lithium batteries.

AST breakthrough

With the optional Acoustic Surface Tracking (AST) firmware you can measure the long waves (swell), storm waves and the short waves generated from local winds. Moreover, the AST also gives you the ability to derive wave parameters based on times series analyses, which is a major advantage relative to the classical bottom mounted systems that derive the wave parameters from spectral estimates of pressure or velocity. This means that AWAC can directly measure wave parameters such as Hmax, H1/10, Tmean, etc. which other bottom mounted systems simply cannot.

A more detailed outline of the AST can be found in the AWAC brochure (PDF)

Software

The AWAC software is used to configure the instrument for deployment, retrieve the data and convert all data files to ASCII. In order to calculate the wave parameters, you have the choice between the non-graphical WaveExtract software and the graphical ExploreWave software. For long term projects with multiple deployments and/or multiple stations, the NORDIS software serves as a central database for all your AWAC wave and current data. This software includes automated QC functions and allows you to view your wave and current data across multiple data files. For system integrators, individual DLL and ActiveX® elements are available for integration into Windows® or Windows® CE applications.

• Recording data to internal recorder (stand-alone use) 
• Online conection to shore via cable, modems, or GSM phone

A Nortek interface box is available for long cable applications and/or integrated modem or radio solutions.

Read more about online applications in the AWAC brochure (PDF).

Velocity:

• Velocity range: ±10m/s
• Accuracy: 1% of measured value ±0.5cm/s
• Sampling rate: 1s to several hours
• Maximum profiling range: 30m (1MHz), 50m (600kHz), depending on local conditions
• Cell size: 0.4 to 2m
• Minimum blanking distance: 0.4m

• Maximum depth: 40m (1MHz), 60m (600kHz)
• Data types: pressure, three velocities and surface distance (optional AST)
• Maximum sampling rate: 4Hz AST, 1Hz (1MHz), 2Hz (600kHz) pressure and velocity

• Compass (flux-gate, automatic up/down detection)
• Tilt (liquid level, max 30° tilt)
• Pressure (piezoresistive, resolution better than 0.005% of full scale)
• Temperature (resistive)
• Two analog channels for use with any analog sensors

• I/O: RS232 or RS422
• Baud rate: 300 to 115200
• User control: Handled via WIN32® software or ActiveX® components

• Capacity: 2 MB, upgradable to 26, 82 or 154 MB 
• Profile record: 120 bytes + 9×Ncells
• Wave record: 46 bytes + Nsamples×24

• Weight in air: 5.4 kg
• Weight in water: < 2.0kg
• Dimensions: 210 mm wide, 180 mm tall
• Materials: All plastic and titanium 

Please see the AWAC brochure (PDF) for a full set of specifications