Method and system for determining underwater effective sound velocity
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorsHarold T. Vincent, Sau-Lon James Hu
Life of this patent
Estimating the term…
Abstract
A method and system for determining the effective sound velocity between a source of sound energy located at an initial depth ZS and an actual target located at another depth. A system utilizing a device such as a computer or microprocessor is used for implementing the method of the present invention. An effective sound velocity (“ESV”) matrix is generated wherein ESV values are a function of actual target depth and actual target elevation angle. The ESV matrix is then used to determine the ESV between a source of sound energy located at an initial depth ZS and an actual target located at any depth between ZS and a final target depth ZT.
Claims20
A method for determining the effective sound velocity between underwater points, the method comprising the steps of:
- providing a device for determining the effective sound velocity between the underwater points;
- feeding into the device the sound velocity profile from a source of sound energy located at an initial depth to a predetermined final target depth;
- feeding into the device a predetermined set of grazing angles;
- feeding into the device a predetermined number of target depths between the initial depth and the final target depth;
- calculating for each grazing angle and target depth a corresponding elevation angle and an effective sound velocity;
- feeding into the device a predetermined uniform set of elevation angles;
- determining for each elevation angle of the uniform set a pair of calculated elevation angles that correspond to a pair of successive grazing angles and a particular target depth wherein the particular elevation angle of the uniform set is between the pair of calculated elevation angles;
- interpolating the calculated effective sound velocity values associated with each elevation angle of the pair of calculated elevation angles to produce an interpolated effective sound velocity;
- repeating for each target depth used between the initial depth and the final depth the above-mentioned steps of determining for each elevation angle of the uniform set of pair of calculated elevation angles and interpolating the calculated effective sound velocity values;
- feeding parameters associated with an actual target, the parameters comprising an actual target depth and an actual target elevation angle;
- and
- selecting as the effective sound velocity between the source of sound energy and the actual target the interpolated effective sound velocity that corresponds to an elevation angle of the uniform set and a target depth that matches the actual target elevation angle and actual target depth, respectively.
A system for determining the effective sound velocity between underwater points, comprising:
- a device for determining the effective sound velocity between the underwater points;
- means for feeding into the device the sound velocity profile from a source of sound energy located at an initial depth to a predetermined final target depth;
- means for feeding into the device a predetermined set of grazing angles;
- means for feeding into the device a predetermined number of target depths between the initial depth and the final target depth;
- means for calculating for each grazing angle and target depth a corresponding elevation angle and an effective sound velocity;
- means for feeding into the device a predetermined uniform set of elevation angles;
- means for determining for each elevation angle of the uniform set a pair of calculated elevation angles that correspond to a pair of successive grazing angles and a particular target depth wherein the particular elevation angle of the uniform set is between the pair of calculated elevation angles;
- means for interpolating the calculated effective sound velocity values associated with each elevation angle of the pair of calculated elevation angles to produce an interpolated effective sound velocity;
- means for repeating the steps of determining for each elevation angle a pair of matching grazing angles and a particular target depth for each target depth fed in the step of feeding into the device a predetermined number of target depths between the initial depth and the final depth;
- means for feeding parameters associated with an actual target, the parameters comprising an actual target depth and an actual target elevation angle;
- and
- means for selecting as the effective sound velocity between the source of sound energy and the actual target the interpolated effective sound velocity that corresponds to an elevation angle of the uniform set and a target depth that matches the actual target elevation angle and actual target depth respectively.
Dependencies are inferred from the claim text.