VLA – Vertical Line Array

The Vertical Line Array (VLA), is a system for recording, visualization and storing of underwater acoustic signals.

The VLA is capable of continuously recording four acoustic signals, covering all frequencies from 30Hz to 100kHz. The system is capable of sample rates up to 384 kS/s on all four channels simultaneously. Acoustic signals are sampled with a resolution of 16 bits and are stored as WAVE-files. Time and GPS-position is also stored in an accompanying .csv file.

The system consists of the following parts:

  • Vertical line consisting of a 225m cable with connectors for four hydrophones, each spaced 30m apart, as well as mechanical termination in both ends.
  • Adjustable bottom laden for straightening the line vertically.
  • Four hydrophones with protective cages, to be attached to the vertical line.
  • Winch for releasing and hauling the line.
  • The control station, containing all the electronics necessary for data acquisition, including battery backup.
  • GPS receiver for time synchronization and position logging.
  • Rugged computer for control, visualization and storing of the recorded acoustics.
  • Deck cable to connect the winch drum mid outlet to the control station.

The control station contains an audio output jack (3,5mm) and a 4-channel audio mixer that allows the operator to listen to the acoustics in real-time. The PC software visualize plots for frequency spectrum (FFT) and amplitude-plot for a chosen channel in real-time, as well as information about logging status, position and time. The PC software also contain controls to start/stop recording, and options to configure sample rate and settings for wave-file and log-files.

Scanmatic may customize VLA for customer’s need.