Military & Homeland Security

Fiber Optic Undersea Surveillance Arrays and Sensing Cables

The USSI system is comprised of three key integrated building blocks and is scalable for very large (many hundreds of sensors) systems. The three main building blocks are the all-optical acoustic sensor cable, the interrogator and the acoustic processor unit (APU).

The sensor cable is a high sensitivity, fiber optic assembly allowing detection of very low sound pressure level disturbances.  The interrogator is designed to provide a very high fidelity digital reproduction of each detected event with high linearity and dynamic range, with stable signal scaling and low distortion.  The APU is a high efficiency processing and display engine designed for accurate classification and easy learning of threats and ‘friendly’ noise events.  If desired, the APU can include a beamformer.

The heart of the USSI System is the low cost all-optical acoustic sensor cable.  It is the first acoustic hydrophone cable that has been designed from the ground up for fully-automated manufacturing.   The fiber itself is the sensing element, with FBG pairs providing low intensity reflections at specific locations to separate the individual hydrophone elements.  A cutaway of one of our actual acoustic surveillance cables is shown at right.  It is approximately 1 inch in diameter has a break strength of 10,000 pounds.  

Our perimeter security cable is typically under ¼ inch in diameter and has a break strength of several hundred pounds.  Since it is designed to be buried, it also incorporates rodent protection. 

 

The Figures to the right depict the ease of installation, trenching, cable installation, and burial.