LFA and CFLA Acoustic Sensors
Navy SBIR FY2013.1

Sol No.: Navy SBIR FY2013.1
Topic No.: N131-050
Topic Title: LFA and CFLA Acoustic Sensors
Proposal No.: N131-050-0933
Firm: AventuSoft L.L.C.
1560 Sawgrass corporate parkway, 4th flo
Sunrise, Florida 33323
Contact: Kevin Jones
Phone: (954) 331-4691
Web Site: www.aventusoft.com
Abstract: This Phase I project will develop an innovative signal processing and information processing concept for improved detection in acoustically noisy littoral waters using existing towed arrays or hull-mounted arrays. These relatively shallow waters have many sources of noise and interference which make it difficult to track the multiple targets with classical filtering approaches such as particle filters or Kalman filtering. It is a multisource problem because of background noise sources and the natural tendency of the multiple signals to overlap. This project proposes an evolutionary approach by building on currently-used detection algorithms using a new probabilistic framework to determine the instantaneous localization (azimuth, range, and depth) of multiple targets and their trajectories in the short-term by spatio-temporal clustering. Autonomous detection and localization using long-term signal clustering with the Bayesian Information Criterion allows targets to be tracked as they move through the noisy littoral space. Outputs from existing systems can also be directly processed by this framework to further improve sonar performance. The Phase I research objectives are to evaluate with underwater acoustic sounds and establish feasibility of the system for improved performance in active clutter reduction that reduces false alarms and improves performance in detection, classification, tracking, and displays.
Benefits: The system developed through this research has potential for several military and commercial applications. The acoustic localization and tracking could be used on platforms such as surface ships and shore surveillance installations to improve the detection of underwater targets. For the military this may be submarines, torpedoes or other objects moving in and under water. The noise reduction capabilities developed through this proposal have application to other detection technologies and applications in addition to the tracking developed herein. A civilian application for the noise reduction, localization and tracking developed here is the study of underwater wildlife. An additional application is in the analysis of heart sounds to detect disease. Acoustic localization and tracking technology developed through this proposal can be leveraged in the following powerful ways: 1. The Low Frequency Active (LFA) systems and the Compact LFA (CFLA) systems can use these algorithms to improve their accuracy in detecting underwater sound signals, as future undersea warfare requirements continue to transition to littoral ocean regions. 2. The algorithms provides a considerable advantage to navigation solutions by: (a) providing a new type of measurement, of acoustical awareness intelligence and self-localization in unstructured environments to, enhance performance and accuracy; (b) providing a new type of measurement whose properties provide robustness; audition has several unique properties that make is specifically advantageous for navigation; and (c) efficiently providing a large number of low-bandwidth measurements whose composite constitutes a considerable augmentation of system accuracy and enhances navigation and path planning by providing the where, who and what of nearby sounds. 3. Vehicle distance determination: the spacing between vehicles can be accurately determined which allows a driver to be alerted when he or she is closing too fast on a forward especially if it is obscured by smoke, fog, or other environmental/military scenarios that obstruct the line of sight.