Navalgund Rao


It is argued that the probability that ultrasound used at the intensities employed clinically will cause bioeffects characteristic of transient cavitation is immensely greater above a threshold peak intensity of the interrogating ultrasound pulse. Simulations and experiments in nonattenuating media show that a factor of 16 to 50 reduction in peak intensity is possible without sacrificing the signal primarily used for imaging, or the resolution. This factor depends on the effective time-bandwidth product of the frequency modulated pulse. However, in a frequency-dependent attenuating medium, such as soft tissue, this advantage could diminish. A linear-frequency and linear-phase model for attenuation was incorporated in the simulation process. The time-bandwidth product was evaluated for reflectors at various depths and as a function of the center frequency and bandwidth of the frequency-modulated pulse.

Date of creation, presentation, or exhibit



Proceedings of the 3rd Annual IEEE Symposium on Computer-based Medical Systems (1990) 89-96 "Frequency modulated pulse for ultrasonic imaging in an attenuating medium," Proceedings of the 3rd Annual IEEE Symposium on Computer-based Medical Systems. The Institute of Electrical and Electronics Engineers. Held in Chapel Hill, North Carolina: 3-6 June 1990. ©1990 Institute of Electrical and Electronics Engineers (IEEE). Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder. This work was supported in part by American Heart Association grant-in-aid award N. 881095. I would like to acknowledge help of Sumat Mehra in performing some of the simulations. ISBN: 0-8186-9040-2Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

Document Type

Conference Proceeding

Department, Program, or Center

Chester F. Carlson Center for Imaging Science (COS)


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