Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring...
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![Page 1: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/1.jpg)
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Characterization Presentation
Performed by:Ron Amit
Supervisor: Tanya ChernyakovaSemester: Spring 2012
Sub-Nyquist Sampling in Ultrasound Imaging
![Page 2: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/2.jpg)
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Ultrasound Device:
![Page 3: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/3.jpg)
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Problem:Modern devices require large number of receivers
Acoustic pulses are of high bandwidthTypical Nyquist rate is 20 MHz * Number of receivers
Large amount of data must be processedHigh computational cost
![Page 4: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/4.jpg)
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Solution:
Reduce sample rate, while still extracting the same required information for image reconstruction
![Page 5: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/5.jpg)
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FRI Model:
• Lower bound of sample rate:
![Page 6: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/6.jpg)
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Single receiver solution:
Unknown parameters are extracted from low rate samples.
![Page 7: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/7.jpg)
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Multichannel Sampling Scheme:
Different sampling scheme for a single receiver, using bank of integrators
![Page 8: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/8.jpg)
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Problem :Low SNR of received signal at a single
receiver.
Solution : Use array of receivers and combine the received
signals – Beamforming process.Beamformed signal has improved SNRRepresents reflections from a single angle –
forming an image line
![Page 9: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/9.jpg)
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Beamforming:
![Page 10: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/10.jpg)
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Compressed Beamforming:
• Combines Beamforming and sampling process.• Received signals are sampled at Sub-Nyquist rate• The scheme’s output is a group of Beamformed signal ‘s
Fourier coefficients• Digital processing extracts the Beamformed signal
parameters
![Page 11: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/11.jpg)
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Using modulation with analog kernels and integration
First Scheme :
Problem : Analog kernels are complicated for hardware implementation
![Page 12: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/12.jpg)
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Simplified Scheme :
• Based on approximating each received signal by only Ki Fourier coefficients
• Each received signal is filtered by a simple analog filter
• Linear transformation on the samples provides the Beamformed signal Fourier coefficients
![Page 13: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/13.jpg)
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Analog Processing
Sub – Nyquist
Sampling
Receiver Elements
Low Rate Samples
Digital Processin
gAmplitudes and delays of reflections
Image Reconstructi
on
Block Diagram:
![Page 14: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/14.jpg)
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Project Goals:Main goal: Prove the preferability of the Xampling method for Ultrasound devices
Sub goals:• Alternative image reconstruction • Optimize algorithm and improve runtime• Explore hardware implementation
![Page 15: Characterization Presentation Performed by: Ron Amit Supervisor: Tanya Chernyakova Semester: Spring 2012 1 Sub-Nyquist Sampling in Ultrasound Imaging.](https://reader035.fdocuments.net/reader035/viewer/2022062421/56649da05503460f94a8bf31/html5/thumbnails/15.jpg)
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Semester 1:Understand and run current code
Improvement:• Image construction from pulses• Lighter OMP algorithm
Semester 2:Algorithm optimization:• Flow graph algorithm• Complexity analysis of subroutines• Runtime optimization
System analysis :• How to implement on processer platform for
maximal performance
Mission Plan:
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אמצע מצגת עד תכנית
29.5-5.6- מ תמונה לייצוג סטנדרטיות שיטות של beamformed dataלימוד
5.6-12.6) ואמפליטודות ) השיות קיימות מתוצאות תמונה של אלטרנטיבי ייצוג
12.6-19.6 , שיטות בשתי שמתקבלות תוצאות בין אלטרנטיבית fine tuningהשוואה שיטה של
19.6-26.6- ה אלגוריתם של תיאורטי נועם, OMPלימוד אצל שמומש האלגוריתם של ניתוח
בחינות 27.7 – 28.6 תקופת
אמצע 1.8 – 27.7 למצגת הכנה