2 Defining recording formats for ADCP netCDF outputs

The EK80 system allows you to record processed data. The data are saved on the hard disk, or on an external data storage device, according to the preferences you have defined. You can also define the which file format to use. One supported file format is the proprietary ADCP netCDF format.

Context

The ADCP netCDF file format is a file format designed by Kongsberg Maritime to hold ADCP velocity data. The format is created as an extension to the ICES SONAR-netCDF4 format using many of the same groups.

Tip

The data files will normally become very large. If you wish to record large amounts of data, make sure that you have enough space on your hard disk. Unless your computer is equipped with a very large disk, we recommend that you save the data to an external storage device.

Set up the file and folder parameters before you start the recording. If you wish to save your recorded data on an external hard disk, make sure that it is connected to the computer.

Procedure

Open the Operation menu.

Select Output.

Observe that the Output dialog box opens. This dialog box contains a number of pages selected from the menu on the left side.

Select File Setup to open the page.

Define the output directory for the recorded files.

In order to change the output directory, both Record RAW and Record Processed recording must be set to Off. The same folder is used for both raw and processed files.

Select Apply to save your choice.

Select Processed Data to File to open the page.

Select the ADCP netCDF file format.

Define a file name prefix.

By adding a prefix to the file names you can identify the files you have recorded during a specific survey.

Define the maximum amount of bytes to be contained in one data file.

Specify the depth range.

The Range setting defines the vertical range from the start depth and down. In other words, this is the vertical distance between the "top" and the "bottom" of the detection area. The EK80 system will only export data retrieved between the sea surface and the selected depth. The depth range is selected in metres.

If relevant, you can use the channel recording range you defined for raw data recording on the File Setup page.

Specify a decimation factor to reduce the sample density and the file size.

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By selecting Decimation with 10 groups of ten samples are averaged.

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By selecting Decimation to Depth Cell Size all samples from the currently selected depth cell are averaged.

Select Add to save the output format.

Select Apply to save your choices.

At the bottom of the Output dialog box, select OK to save the chosen parameters and close it.