USA flag logo/image

An Official Website of the United States Government

Smart Tether for Relative Localization of Moored and Towed Bodies

Award Information

Department of Defense
Award ID:
Program Year/Program:
2004 / STTR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
Applied Physical Sciences Corp.
475 Bridge Street Suite 100 Groton, CT -
View profile »
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 1
Fiscal Year: 2004
Title: Smart Tether for Relative Localization of Moored and Towed Bodies
Agency / Branch: DOD / NAVY
Contract: N00014-04-M-0257
Award Amount: $69,998.00


Determining a geo-reference of an underwater object is a critical requirement for marine applications such as mine-hunting and marine surveying. Although a GPS fix can be obtained at the surface, the watch circle of a tether connecting a surface and underwater body can impose positional errors that are far greater than GPS errors. Here we propose to develop a technology to automatically determine the geodetic location of an underwater body by acoustically measuring the relative position vector to a surface expression, equipped with an acoustic transmitter. The proposed system makes use of vector hydrophones, allowing determination of the bearing of a surface expression relative to a moored body with a single, relatively small sensor. Significantly, the angle of arrival accuracy of vector sensor is nearly independent of frequency, facilitating a compact, low frequency localizing system. This is an important consideration in very shallow water or surf zone regions where bubbles and suspended sediment can have impose enormous high frequency acoustic attenuation. The proposed system is envisioned to provide a low cost, general purpose solution to a host of underwater positioning applications. One important potential application to be investigated is the enabling of a sea-based Differential Global Positioning Base Station.

Principal Investigator:

Jason Rudzinsky
Senior Engineer

Business Contact:

David Horne
Business Manager
Small Business Information at Submission:

2 State Street, Suite 300 New London, CT 06320

EIN/Tax ID: 010655626
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Research Institution Information:
Woods Hole Oceanographic Institutio
98 Water Street
Woods Hole, MA 02543
Contact: M. Tavares
Contact Phone: (508) 289-2462
RI Type: Domestic nonprofit research organization