L-3 Communications
LFATS VDS-100 - Variable Depth Sonar System

The VDS-100 is a low frequency, variable depth, active sonar system used on surface ships to detect, localize and prosecute all types of submarines. It has been specifically designed for small ships operating in shallow water against modern diesel-electric submarine threats.

Using proven technology derived from our HELRAS helicopter DS-100 dipping sonar, the VDS-100 system is designed for high performance at a lower operating frequency, with easy installation, removal and handling from ships of various sizes, including frigates, corvettes, small patrol craft and platforms of opportunity.

The low frequency of the variable depth sonar manifests in a long wavelength capable of penetrating most submarine cladding schemes. The VDS-100 sonar achieves high resolution of low Doppler targets and is able to operate at depths between 15 and 300 meters.

The VDS-100 consists of a towed body, a compact integrated winch and handling system, and an onboard processing subsystem. Inboard electronics include the transmit power amplifier and the sonar processing unit, which was designed with an open architecture configuration to accommodate future technology. The system can be used in stand-alone mode or integrated into a ship's combat system.

Click here to see data sheet.
The transmit array contained in the body of the towed vehicle consists of 16 compact projector elements. An innovative array extension and retraction mechanism enables the system to develop high-transmit directivity. Return signals are received by up to four small-diameter, liquid-filled linear towed arrays.

VDS-100 processing involves multiple ping wave trains, multidimensional target clustering and averaging, target discrimination against high background noise in shallow water environments, own-ship noise cancellation, Doppler nullification, and CW and HFM wave train generation and processing.