P071

Precise Positioning of a Transponder Placed on a sea Floor (2)

A0178 Hiroshi Isshiki Institute of Mathematical Analysis

In the first report, not only the position of a sea bottom

transponder but also the underwater acoustic velocity can be

determined, if the position of sea surface transponders and the

distances between the surface and bottom transponders are known. In

the present report, a theoretical possibility of obtaining the

position of the sea bottom transponder with accuracy of centimeter

order is shown. For the purpose, estimation of the underwater

acoustic velocity distribution as a part of solution is extremely

important. Effects of errors in the positions of the surface

transponders and the distances between the surface and bottom

transponders are also obtained in detail.

In the previous papers, two dimensional calculations are conducted.

In the present paper, more realistic simulations are conducted by

introducing three dimensional calculations. And a new idea called

method of incremental layers are developed to stabilize numerical

calculations.

The effects of current are also discussed.