Acoustic Positioning System for Submerged Vehicles.
Experience conducting research with the US Naval submarine fleet and
other Arctic endeavors has shown that both manned and unmanned submarine
vehicles operating in Arctic waters for extended periods suffer from
significant navigational inaccuracies. Ice cover prevents these systems
from acquiring GPS or other fixes to correct inertial systems that have
drifted. Ice camp and ship support is limited to their respective
For the Naval submarine fleet and the research conducted aboard
these ships, correcting navigational inaccuracies translates to days of
lost time. Locating surfacable features and obtaining GPS fixes requires
on the order of 12 to 48 hours or longer - a significant portion of a 40
day cruise if it must be repeated weekly.
To provide navigational information to submarines, AUVs, rovers, and
other sensors operating in the Arctic, small self deploying buoys
containing GPS receivers and a simple transducer/acoustic modem could be
launched from airplanes over wide areas. Time synchronized with the GPS
time standard, a buoy could transmit its location exactly on the minute.
Vehicles in the area could, in turn, get a bearing and range to determine
their own position. The result would be an effective extension of the
Global Positioning System to subsurface operations in the Arctic.