Toward Semi-real-time GPS/A Seafloor Positioning with a Moored Buoy

Compared with land-based GPS observation, GPS/Acoustic seafloor positioning has critical problems against on-line, continuous, and long-term observations. Since GPS/A observation on a moored buoy can be a solution to cope with these problems, an autonomous GPS/A observation system on a buoy is under development in preparation for a possible future application to the cabled ocean floor observation project DONET funded by the MEXT, Japan. A key point is reduction of power consumption. A low-power GPS receiver will take the place of three GPS receivers, and the acoustic ranging system will be replaced with a battery-driven compact system.