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Updated: Jul 20, 2026
08:21
Wideband Optical Detector of Ultrasound for Medical Imaging Applications
Published on: May 11, 2014
Effect of sparse basis selection on ultrasonic signal representation
Guang-Ming Zhang1, David M Harvey, Derek R Braden
1General Engineering Research Institute, Liverpool John Moores University, Liverpool, United Kingdom. g.zhang@ljmu.ac.uk <g.zhang@ljmu.ac.uk>
Ultrasonics
|August 26, 2006
Summary
This study compares sparse basis selection algorithms for ultrasonic signal analysis in scanning acoustic microscopy (SAM). The focal underdetermined system solver (FOCUSS) algorithm demonstrated superior performance for nondestructive testing applications.
Area of Science:
- Nondestructive testing
- Materials science
- Signal processing
Background:
- Scanning Acoustic Microscopy (SAM) is crucial for microelectronic package failure analysis.
- Adaptive sparse representations enhance SAM performance by decomposing ultrasonic signals.
- Signal decomposition relies on learned dictionaries and sparse basis selection algorithms.
Purpose of the Study:
- To investigate the impact of different sparse basis selection algorithms on ultrasonic signal representation.
- To evaluate algorithm efficiency for various SAM applications including echo detection and imaging.
- To identify the optimal algorithm for improved SAM performance.
Main Methods:
- Examined overcomplete independent component analysis, focal underdetermined system solver (FOCUSS), and sparse Bayesian learning algorithms.
- Performed numerical simulations for quantitative analysis of signal representation efficiency.
- Conducted experiments using ultrasonic A-scans from flip-chip packages.
Main Results:
- The focal underdetermined system solver (FOCUSS) algorithm exhibited the best overall performance.
- Efficiency was evaluated based on waveform estimation, echo detection, echo location, and C-scan imaging.
- FOCUSS provided superior ultrasonic signal representation for SAM applications.
Conclusions:
- Sparse basis selection significantly affects ultrasonic signal representation in SAM.
- The FOCUSS algorithm is recommended for its effectiveness in improving SAM performance.
- This research contributes to advancing nondestructive evaluation techniques in microelectronics.
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