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Direction-of-Arrival Estimation Methods in Interferometric Echo Sounding.
Piotr Grall1, Iwona Kochanska1, Jacek Marszal1
1Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland.
Sensors (Basel, Switzerland)
|June 27, 2020
Summary
This review explores interferometric echo sounder technologies, focusing on multiphase echo sounders. It details direction-of-arrival estimation methods and error sources for improved sea sounding accuracy.
Area of Science:
- Marine geophysics and oceanographic technology.
- Acoustic sensing and signal processing.
Background:
- Two primary sea sounding technologies exist: multibeam echo sounders and multiphase echo sounders (interferometric echo sounders).
- These technologies, while distinct, offer complementary advantages for seafloor mapping.
- Interferometric echo sounders utilize phase difference measurements to determine direction-of-arrival.
Purpose of the Study:
- To review the evolution of interferometric echo sounding array configurations.
- To outline methods for direction-of-arrival estimation in interferometric sonar.
- To focus on advancements leading to state-of-the-art multiphase echo sounders.
Main Methods:
- Review of historical development in interferometric sonar array designs.
- Analysis of classical and modern algorithms for direction-of-arrival estimation.
- Characterization of error sources affecting phase difference measurements.
Main Results:
- The article details modifications to interferometric sonar arrays that have advanced multiphase echo sounder technology.
- Key algorithms for direction-of-arrival estimation are presented.
- Accuracy is shown to depend on array configuration and noise sources.
Conclusions:
- Interferometric echo sounding has evolved significantly, particularly with multiphase systems.
- Understanding array configurations and error sources is crucial for accurate seafloor mapping.
- Future research aims to enhance accuracy and explore broader applications of interferometric principles.
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