Sonar Characterization Using Active Calibration Transponders
Abstract
There is interest in the mine countermeasures (MCM) community regarding the utility of calibrated synthetic aperture sonar (SAS) im"agery, where pixels in the scene are mapped to backscatter cross section. Intuitively, having more information about the sea floor s""hould improve the Navy~s ability to detect/classify mines. But, any real advantage has yet to be proven. This program will investiga""te the utility of a programmable active calibration transponder (PACT) for acoustic MCM sensing modes, beginning with SAS imaging. I""n addition to imaging, a PACT capability may prove useful for assessing the performance of acoustic color measurements, where there" is a desire to create the equivalent of ~resolution targets~ commonly used for imaging systems. The PACT can be programmed to trans"mit signatures that are difficult, or even impossible, to realize with passive targets. For example, itcan be programmed to respond"" with an arbitrarily-long CW tone, resulting in very sharp peaks in the frequency signature. The PACT can also be programmed to tran""smit a given signal on only a single ping, emulating a target with a very narrow angular response. These capabilities can be used to"" experimentally assess notions of resolution and SNR in the acoustic color domain.Moving beyond the sensors themselves, the capabil"ities offered by a PACT can be used to help develop and assess novel signal processing and ATR algorithms which may not rely on traditional intermediate products such as imagery.The research will consist of both theoretical work and field experimentation aimed at" better understanding what useful information can be measured using an active transponder, as opposed to more classical passive refl"ectors such as metal spheres. The theoretical component will consider the kinds and quality of information that can be gathered using ~in-situ~ calibration methods where the sensor payload and PACT are used in a cooperative manner. The experimental aspect of the program will employ the transponder to collect at-sea calibration measurement data that can be shared with the MCM research community". It is expected that transponder collections can occur in conjunction with routine experimentation, eliminating theneed for dedica""ted test events.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 01, 2017
- Source ID
- N000141712877
Entities
People
- Daniel Cook
Organizations
- Georgia Tech Applied Research Corporation
- Office of Naval Research
- United States Navy