Additional Mine Classification Capabilities for the INSS
Abstract
As a diver scans shallow water or very shallow water (SW/VSW) area with an INSS high frequency sonar, many objects may be detected or imaged in the scene. The objective of this project is to develop algorithms that capture the broadband echo responses from these objects detected by the INSS and extract special echo features to assist in target discrimination from the background. The algorithms are based upon geometric acoustics, broadband array and signal processing techniques, and the physics of elastic waves on thin shells. Initially, three algorithms were investigated for acoustic robustness. These were, Shell Thickness Resonance (STR) Frequency Notch to estimate the targets shell thickness, Local Target to Bottom Multi-path Echo to discriminate cylindrical and spherical objects, and Multi-channel Phase Comparison (MPC) to estimate the target's height. The third algorithm, MPC, was the most acoustically robust, but required a modification to the INSS array geometry. The first algorithm, STR, was sufficiently robust to be implemented within an INSS unit and tested with Navy and ARL:UT divers. The implementation required reductions in the algorithm's capabilities to fit within the lNSS hardware and software architecture. Three sets of diver tests were conducted In Lake Travis Texas and Coronado California. The final recommendation was to not modify the current operational systems but to consider the STR and MPC algorithms as part of the target sensing and discrimination suites in future Implementations of broadband sonar systems.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 10, 2003
- Accession Number
- ADA417359
Entities
People
- Charles M. Loeffler
- Min F. Chang
Organizations
- University of Texas at Austin