Date: November 18, 2005

Time: 3:00 p.m.

Location: GCATT Room 325

Speaker(s): Daniel A. Cook

Title: Overview of Synthetic Aperture Sonar

Abstract:
Synthetic Aperture Sonar (SAS), like its radar counterpart (SAR), is a technology for producing very high-resolution imagery of distant scenes. Synthetic aperture processing effectively allows the user to employ small physical apertures at the expense of increased signal processing complexity. First conceived in the late 1970's, SAS is only now reaching a stage of maturity that qualifies it for widespread use. This talk will provide the audience with an overview of the history of SAS technology, its applications, the technical problems faced by those who wish to use it, and current research areas of interest. Specific emphasis will be placed on the problem of motion estimation and compensation: that is, producing a well-focused SAS image in spite of the unwanted motion (deviation from the ideal collection path) of the platform carrying the sonar. Most operational SAS systems are carried by autonomous underwater vehicles (AUVs). These vehicles are outfitted with inertial navigation units, the output of which is combined with the SAS data itself to produce a refined estimate of the motion of the vehicle. This estimate is then used to compensate the SAS data for the vehicle motion. Two examples of the systems to be discussed can be viewed at the web sites below:

http://www.whoi.edu/home/about/annualreport04/research/highlights_robot.html

http://www.bluefinrobotics.com/payloads.htm

Bio:
Dan Cook received the BS and MS in Mechanical Engineering in 1998 and 2000 from Georgia Tech. Since 2000, he has been employed at the Naval Surface Warfare Center in Panama City, FL where he works with the processing algorithms used by the US Navy's synthetic aperture sonar program.

Date:	November 18, 2005
Time:	3:00 p.m.
Location:	GCATT Room 325
Speaker(s):	Daniel A. Cook
Title:	Overview of Synthetic Aperture Sonar
Abstract:	Synthetic Aperture Sonar (SAS), like its radar counterpart (SAR), is a technology for producing very high-resolution imagery of distant scenes. Synthetic aperture processing effectively allows the user to employ small physical apertures at the expense of increased signal processing complexity. First conceived in the late 1970's, SAS is only now reaching a stage of maturity that qualifies it for widespread use. This talk will provide the audience with an overview of the history of SAS technology, its applications, the technical problems faced by those who wish to use it, and current research areas of interest. Specific emphasis will be placed on the problem of motion estimation and compensation: that is, producing a well-focused SAS image in spite of the unwanted motion (deviation from the ideal collection path) of the platform carrying the sonar. Most operational SAS systems are carried by autonomous underwater vehicles (AUVs). These vehicles are outfitted with inertial navigation units, the output of which is combined with the SAS data itself to produce a refined estimate of the motion of the vehicle. This estimate is then used to compensate the SAS data for the vehicle motion. Two examples of the systems to be discussed can be viewed at the web sites below: http://www.whoi.edu/home/about/annualreport04/research/highlights_robot.html http://www.bluefinrobotics.com/payloads.htm
Bio:	Dan Cook received the BS and MS in Mechanical Engineering in 1998 and 2000 from Georgia Tech. Since 2000, he has been employed at the Naval Surface Warfare Center in Panama City, FL where he works with the processing algorithms used by the US Navy's synthetic aperture sonar program.