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Time and frequency constrained sonar signal design for optimal detection of elastic objects
Brandon Hamschin1, Patrick J Loughlin
1Applied Physics Laboratory, The Johns Hopkins University, Laurel, Maryland 20723, USA. Brandon.Hamschin@jhuapl.edu
The Journal of the Acoustical Society of America
|April 6, 2013
Summary
This study introduces two novel methods for designing optimal transmit signals to detect elastic objects. These methods minimize signal duration while preserving spectral characteristics crucial for detection in noisy environments.
Area of Science:
- Signal Processing
- Acoustic Detection
- Model-Based Systems
Background:
- Optimizing detection relies on effective transmit signal design.
- Previous work focused on spectral magnitude optimization for detection.
- Elastic objects and various noise sources require specific signal characteristics.
Purpose of the Study:
- Develop methods for synthesizing minimum duration signals with optimal spectral magnitude.
- Design signals for detecting elastic objects in additive and self-noise.
- Analyze the relationship between signal duration and spectral properties.
Main Methods:
- Two distinct waveform synthesis approaches are presented.
- Method 1: Preserves optimal spectral magnitude while minimizing temporal duration.
- Method 2: Maximizes temporal energy concentration with near-optimal spectral magnitude.
Main Results:
- Both methods yield signals optimal for detecting elastic objects.
- An analytical connection is established between the two synthesis approaches.
- Simulations demonstrate the effectiveness of the developed signal design techniques.
Conclusions:
- The developed methods offer practical solutions for model-based transmit signal design.
- The findings are applicable to scenarios involving elastic targets and complex noise.
- Future work can explore real-world model acquisition for target and environment.
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