Paper
24 February 2012 Frequency, bandwidth, and information transfer in B-mode imaging
Author Affiliations +
Abstract
Center frequency and bandwidth are two generic parameters used to characterize transmitted pulse profiles in B-mode ultrasonic imaging. Increasing either is generally thought to improve spatial resolution in the final image, but at a potential cost of lower signal-to-noise ratio, with no general understanding of where they are optimal. In this work we investigate their role in converting the acquired radio-frequency signal from a linear array into an envelope image. Statistics of the backscattered signal, based on Rayleigh-Sommerfeld diffraction theory, are used in an ideal observer calculation that quantifies the task-relevant information contained in the radio-frequency (RF) signal. We then compare two approaches to computing an envelope image. The first is a standard B-mode envelope from the complex analytic signal. The second approach processes RF through a Wiener filter before forming an analytic signal. Effects of envelope detection are measured by computing the ideal observer in the envelope domain using Smith-Wagner approximations. Over frequencies ranging from 3-15MHz and fractional bandwidths ranging from 20% to 80%, we find that information transfer in the envelope varies widely with task. There is a substantial loss of information in all conditions in the formation of a standard envelope. Efficiency relative to the RF ranges from 60% to less than 5%. The Weinerfiltered envelope images substantially improve efficiency in two of the three tasks investigated. In the third task, the results are mixed, but we argue that the Weiner filter may be improved substantially by retuning it to the interior of a lesion.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Craig K. Abbey, Nghia Q. Nguyen, and Michael F. Insana "Frequency, bandwidth, and information transfer in B-mode imaging", Proc. SPIE 8320, Medical Imaging 2012: Ultrasonic Imaging, Tomography, and Therapy, 83200I (24 February 2012); https://doi.org/10.1117/12.912430
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Filtering (signal processing)

Signal processing

Image processing

Signal analyzers

Signal attenuation

Signal to noise ratio

Reflectivity

RELATED CONTENT

Computation and meaning of Gabor coefficients
Proceedings of SPIE (December 01 1991)
Radio Imaging Of Launch Vehicles And Payloads
Proceedings of SPIE (May 18 1988)
Far field focusing of laser beam based on digital image...
Proceedings of SPIE (November 10 2010)
Wigner higher-order moment spectra: a review
Proceedings of SPIE (November 30 1992)
New method for preprocessing in airborne SAR system
Proceedings of SPIE (April 30 2003)

Back to Top