Bobber field acoustic detection system

Patent metadata

Field	Value
Publication number	US-10107907-B2
Application number	US-201614986968-A
Country	US
Kind code	B2
Filing date	Jan 4, 2016
Priority date	Jan 4, 2016
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

Embodiments described herein relate to generating an image of an acoustic field associated with an underwater region. A plurality of submersible sensing devices (SSDs) are disposed so as to be substantially separate from each other in an underwater region, wherein each respective SSD is configured to execute a sink/float mission. During at least a portion of the sink/float mission, within each SSD, an environmental sensor measures at least one environmental parameter, a position sensor detects position information, an acoustic detection sensor detects at least one underwater signal, and a data recording system records mission data. After the sink/float mission, a processor receives mission data from the SSDs and generates an acoustic field image. Advantageously, during the sink/float mission some SSDs can transmit an orthogonal high time-bandwidth signal to help prevent interference between SSD during acoustic detection.

First claim

What is claimed is:

1. A system for generating an image of an acoustic field associated with an underwater region, the system comprising:
a plurality of submersible sensing devices (SSDs) disposed so as to be substantially separate from each other in the underwater region, each respective SSD configured to execute a sink/float mission in water, the sink/float mission comprising movement of the SSD from at least a first depth in water to at least a second depth in water, each respective SSD comprising:
an environmental sensor configured to measure, during at least a portion of the sink/float mission, at least one environmental parameter along at least a portion of a path taken by the SSD during a sink/float mission;
a position sensor configured to detect position information associated with the SSD during at least a portion of the sink/float mission, during a least a portion of the sink/float mission; wherein the position information further comprises at least one of:
(a) a first set of position information taken at substantially the same time that at least one environmental parameter is being measured; and
(b) a second set of position information taken at substantially the same time that at least one underwater acoustic signal is being detected;

an acoustic detection sensor configured to detect, during at least a portion of the sink/float mission, at least one underwater acoustic signal during at least a portion of the sink/float mission;
a data recording system in operable communication with the environmental sensor, the position sensor, and the acoustic detection sensor, the data recording system configured to record a set of mission data during at least a portion of the sink/float mission, the set of mission data comprising data from the environmental sensor, data from the position sensor, and data from the acoustic detection sensor;
a buoyancy control system configured to control buoyancy of the SSD during the sink/float mission; and
a communications system configured to transmit, at a predetermined time, at least a portion of the mission data from the SSD to a processor located remotely from the plurality of SSDs; and

a processor in operable communication with the plurality of SSDs, the processor configured to:
receive the set of mission data from at least a portion of the plurality of SSDs; and
generate an acoustic field image based at least in part on the received mission information.

2. The system of claim 1 , wherein the position information further comprises at least one voxel position of the SSD and wherein the processor is further configured to:
determine, based on the received mission data, a set of corresponding respective path, and voxel position information for each respective SSD in the portion of the plurality of SSDs, during each respective sink/float mission undertaken by the respective SSD in the portion of the plurality of SSDs;
generate, based at least in part on the at least one environmental parameter, a propagation model of the underwater region;
perform a first adjustment of at least one of the path, voxel position, and detected acoustic signal information for each SSD based at least in part on the propagation model; and
generate the acoustic field image based at least in part on the path, voxel position, and detected acoustic information after the first adjustment.

3. The system of claim 1 wherein the SSD further comprises an acoustic transmitter configured to transmit from the SSD at least one unique transmitted signal at a frequency compatible with transmission in water.

4. The system of claim 3 , wherein the unique transmitted signal comprises an orthogonal high time-bandwidth signal.

5. The system of claim 3 , wherein each of the plurality of the SSDs comprises an acoustic sensor configured to use two-way bi-static reflection sensing to detect acoustic signals.

6. The system of claim 3 , wherein the at least one acoustic signal comprises monostatic and bistatic reflected returns.

7. The system of claim 6 , wherein, for a given respective SSD, at least a portion of the reflected returns comprise reflections based at least in part on the at least one unique transmitted signal sent from that given respective SSD.

8. The system of claim 5 , wherein the processor is further configured to:
perform a second adjustment of at least one of the path, voxel position, and detected acoustic signal information based at least in part on information relating to two-way bistatic reflection sensing between two or more SSDs; and
generate an acoustic field image based at least in part on the path, voxel position, and detected acoustic information after the first and second adjustments.

9. The system of claim 1 , wherein the processor is configured to generate a sound velocity profile (SVP) based at least in part on the measured environmental parameter.

10. The system of claim 1 , wherein at least a portion of the plurality of SSDs is configured to be synchronized in time during at least one sink/float mission.

11. The system of claim 1 , wherein the SSD comprises at least one of a sonobuoy, bobber, and dropsonde.

12. The system of claim 1 , wherein at least a portion of the SSDs are configured such that their respective transmitted signals overlap in interrogation radius without causing interference with other respective transmitted signals.

13. The system of claim 1 , wherein, for at least a portion of the plurality of SSD devices, the first set of position information is taken at substantially the same time as the second set of position information.

14. A submergible sensing device (SSD) configured to execute a sink/float mission in water, the sink/float mission comprising movement of the SSD from at least a first depth in water to at least a second depth in water, the SSD comprising:
an environmental sensor configured to measure, during at least a portion of the sink/float mission, at least one environmental parameter along at least a portion of a path taken by the SSD during a sink/float mission;
a position sensor configured to detect position information during at least a portion of the sink/float mission, the position information comprising at least one voxel position of the SSD, during a least a portion of the sink/float mission, wherein the position information further comprises at least one of:
(a) a first set of position information taken at substantially the same time that at least one environmental parameter is being measured; and
(b) a second set of position information taken at substantially the same time that at least one underwater acoustic signal is being detected;

an acoustic detection sensor configured to detect, during at least a portion of the sink/float mission, the at least one underwater acoustic signal;
a data recording system in operable communication with the environmental sensor, the position sensor, and the acoustic detection sensor, the data recording system configured to record a set of mission data during at least a portion of the sink/float mission, the set of mission data comprising data from the environmental sensor, data from the position sensor, and data from the acoustic detection sensor; and
a buoyancy control system configured to control buoyancy of the SSD during the sink/float mission.

15. The SSD device of claim 12 , further comprising a communications system configured to transmit, at a predetermined time, at least a portion of the mission data from the SSD to a processor located remotely from the SSD.

16. The SSD of claim 14 , further comprising an acoustic transmitter configured to transmit from the SSD at least

Assignees

• Raytheon Bbn Technologies Corp
• Raytheon Bbn Tech Corporation

Inventors

• Nicoletti Michael John
• Daily Matthew Patrick

Classifications

• B63B2207/02

  Variable ballast or buoyancy · CPC title

• B63B2211/02

  Oceanography · CPC title

• H04B11/00

  Transmission systems employing ultrasonic, sonic or infrasonic waves · CPC title

• G10K11/006

  Transducer mounting in underwater equipment, e.g. sonobuoys · CPC title

• G01S15/003

  Bistatic sonar systems; Multistatic sonar systems · CPC title