Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49370
K. Tsubouchi, T. Tomioka, T. Sato, C. Endo, N. Mikoshiba
The authors have developed a compact spread-spectrum (SS) wireless modem using a SAW (surface acoustic wave) convolver (the efficient ZnO-SiO/sub 2/-Si Sezawa wave convolver). The SS modem was based on a DS (data-scanning) method, where the PN (pseudonoise) code length was 127 bits and the code rate was 14 MHz. The demodulation method of the SS modem was a completely asynchronous one, which was very useful for application to wireless communication under the very weak signals. From 1989 in Japan, the allowed electric field of a transmitter without a license will be less than 500 mu V/m at 3 m in the frequency range less than 322 MHz. Under this restriction the usual narrowband FM modem was effective only within a distance less than 11 m. The SS modem proved to be reliable for distances as far as 110 m.<>
{"title":"An asynchronous spread spectrum wireless-modem using a SAW convolver","authors":"K. Tsubouchi, T. Tomioka, T. Sato, C. Endo, N. Mikoshiba","doi":"10.1109/ULTSYM.1988.49370","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49370","url":null,"abstract":"The authors have developed a compact spread-spectrum (SS) wireless modem using a SAW (surface acoustic wave) convolver (the efficient ZnO-SiO/sub 2/-Si Sezawa wave convolver). The SS modem was based on a DS (data-scanning) method, where the PN (pseudonoise) code length was 127 bits and the code rate was 14 MHz. The demodulation method of the SS modem was a completely asynchronous one, which was very useful for application to wireless communication under the very weak signals. From 1989 in Japan, the allowed electric field of a transmitter without a license will be less than 500 mu V/m at 3 m in the frequency range less than 322 MHz. Under this restriction the usual narrowband FM modem was effective only within a distance less than 11 m. The SS modem proved to be reliable for distances as far as 110 m.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133995981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49520
F. Kremkau, R. Hantgan
Experimental results on the absorption of ultrasound in solutions of biomacromolecules are presented. Absorptions of albumin in four buffers indicate that their presence affects absorption supporting a solvation mechanism. Proline, bacitracin, hemoglobin, and three synthetic phosphatidyl choline lipids all have increased absorptions in organic solvents. Absorptions for protein mixtures at pHs where one molecule has negative net charge and the other positive do not indicate a relevant role for electrostatic interactions in absorption. Glutaraldehyde polymerization of an albumin solution caused no change in absorption. Lipid absorption measurements support interaction observations with proteins. From these results it is concluded that molecular size, structure, solvation, and solute interactions are relevant factors in the absorption of ultrasound in biological material.<>
{"title":"Absorption of ultrasound in biomolecular solutions","authors":"F. Kremkau, R. Hantgan","doi":"10.1109/ULTSYM.1988.49520","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49520","url":null,"abstract":"Experimental results on the absorption of ultrasound in solutions of biomacromolecules are presented. Absorptions of albumin in four buffers indicate that their presence affects absorption supporting a solvation mechanism. Proline, bacitracin, hemoglobin, and three synthetic phosphatidyl choline lipids all have increased absorptions in organic solvents. Absorptions for protein mixtures at pHs where one molecule has negative net charge and the other positive do not indicate a relevant role for electrostatic interactions in absorption. Glutaraldehyde polymerization of an albumin solution caused no change in absorption. Lipid absorption measurements support interaction observations with proteins. From these results it is concluded that molecular size, structure, solvation, and solute interactions are relevant factors in the absorption of ultrasound in biological material.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133493035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49519
M. Sherar, F. Foster
The principle, design considerations, and operation of a C-mode, 100-MHz ultrasound backscatter microscope are described. Applications of the C-mode microscope, as well as of a new real time B-mode UBM, to the imaging of an in vitro tumor model and ocular tissue are presented. Central to these developments has been the construction of PVDF (polyvinylidene fluoride) transducers with sufficient sensitivity to detect the small backscatter signals from biological materials and bandwidth capable of giving an axial resolution of approximately 10 mu m. The lateral resolution achieved is 17.5 mu m in the C-scanner using an f/1.33 transducer and 36 mu m in the B-scanner, which uses an f/2 transducer. Future developments are also discussed.<>
{"title":"Ultrasound backscatter microscopy","authors":"M. Sherar, F. Foster","doi":"10.1109/ULTSYM.1988.49519","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49519","url":null,"abstract":"The principle, design considerations, and operation of a C-mode, 100-MHz ultrasound backscatter microscope are described. Applications of the C-mode microscope, as well as of a new real time B-mode UBM, to the imaging of an in vitro tumor model and ocular tissue are presented. Central to these developments has been the construction of PVDF (polyvinylidene fluoride) transducers with sufficient sensitivity to detect the small backscatter signals from biological materials and bandwidth capable of giving an axial resolution of approximately 10 mu m. The lateral resolution achieved is 17.5 mu m in the C-scanner using an f/1.33 transducer and 36 mu m in the B-scanner, which uses an f/2 transducer. Future developments are also discussed.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133433993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49403
Y. Yong, J. Vig
The resonant modes of cylindrically symmetric film bulk acoustic resonators (FBARs) are found by variational analysis. The FBARs under consideration are fabricated by depositing gold, zinc oxide, and aluminum films onto a membrane of fused quartz. The method of analysis allows the transducer and the membrane to have unequal diameters. The primary objective of this work is to investigate the effect of the transducer diameter on the mode spectrum, particularly the intermode spacing. Each trial function used in the analysis is a product of a radial and an axial function. It is desirable for the trial functions to have local support and a certain degree of smoothness. The Schoenberg cubic B-spline satisfies these criteria. Accurate eigenanalyses are available for several-hundred angularly symmetric modes.<>
{"title":"Frequency fluctuations in thickness shear resonators induced by absorption and desorption of surface molecules","authors":"Y. Yong, J. Vig","doi":"10.1109/ULTSYM.1988.49403","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49403","url":null,"abstract":"The resonant modes of cylindrically symmetric film bulk acoustic resonators (FBARs) are found by variational analysis. The FBARs under consideration are fabricated by depositing gold, zinc oxide, and aluminum films onto a membrane of fused quartz. The method of analysis allows the transducer and the membrane to have unequal diameters. The primary objective of this work is to investigate the effect of the transducer diameter on the mode spectrum, particularly the intermode spacing. Each trial function used in the analysis is a product of a radial and an axial function. It is desirable for the trial functions to have local support and a certain degree of smoothness. The Schoenberg cubic B-spline satisfies these criteria. Accurate eigenanalyses are available for several-hundred angularly symmetric modes.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123798517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49365
J. Thoss
A modified form of laser direct writing has been applied to phase compensate reflecting array correlators (RAC). Accurate spatial correction patterns were written by directed laser light, trimming the phase response characteristics of a 3600 TB (time-bandwidth) RAC delay line fabricated on YZ lithium niobate. The resulting time sidelobes were suppressed to -44 dB.<>
{"title":"Improved time-sidelobe performance in SAW RAC's using laser aided phase compensation","authors":"J. Thoss","doi":"10.1109/ULTSYM.1988.49365","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49365","url":null,"abstract":"A modified form of laser direct writing has been applied to phase compensate reflecting array correlators (RAC). Accurate spatial correction patterns were written by directed laser light, trimming the phase response characteristics of a 3600 TB (time-bandwidth) RAC delay line fabricated on YZ lithium niobate. The resulting time sidelobes were suppressed to -44 dB.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125077058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49397
M. Valdois, B. Sinha, J. Boy
The SBTC-cut (stress compensated for the B-mode and temperature compensated for the C-mode) was first predicted in 1981 based on theoretical calculations for the force-frequency effect in thickness-shear quartz resonators. The authors have verified experimentally the stress compensation feature for the fast thickness shear mode of vibration of SBTC-cut quartz resonators. The first set of experimental results consists of measurements made on biconvex contoured, disc resonators of orientation in the neighborhood of SBTC-cut as well as on a RT-cut resonator with a different radius of curvature for the contoured faces. For the resonator design used in the cylindrical probe structure, the motional resistance for the B-mode of vibration was approximately 12% of that of the C-mode. In addition, experimental data were obtained on the temperature dependence of the planar stress coefficient and pressure dependence of the frequency-temperature characteristic for both the thickness-shear modes of the SBTC-cut.<>
{"title":"Experimental verification of stress compensation in the SBTC-cut","authors":"M. Valdois, B. Sinha, J. Boy","doi":"10.1109/ULTSYM.1988.49397","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49397","url":null,"abstract":"The SBTC-cut (stress compensated for the B-mode and temperature compensated for the C-mode) was first predicted in 1981 based on theoretical calculations for the force-frequency effect in thickness-shear quartz resonators. The authors have verified experimentally the stress compensation feature for the fast thickness shear mode of vibration of SBTC-cut quartz resonators. The first set of experimental results consists of measurements made on biconvex contoured, disc resonators of orientation in the neighborhood of SBTC-cut as well as on a RT-cut resonator with a different radius of curvature for the contoured faces. For the resonator design used in the cylindrical probe structure, the motional resistance for the B-mode of vibration was approximately 12% of that of the C-mode. In addition, experimental data were obtained on the temperature dependence of the planar stress coefficient and pressure dependence of the frequency-temperature characteristic for both the thickness-shear modes of the SBTC-cut.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127454459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49533
C. Delebarre, C. Bruneel, P. Miquet
An ultrasonic thickness measurement system for the 20- to 110- mu m range has been developed for thin paint layers on metallic or nonmetallic substrates. In the case of a multilayered sample this system generally furnishes only the sum of the different thicknesses. Thus, a digital signal-processing method has been developed to extract the different values of thickness from the power spectral density. This method is based on a power cepstrum analysis, defined as the Fourier transform of the logarithm power spectral density of the radio-frequency signal. This technique gives, in the case of three layers, the three thicknesses and their linear combinations. Experimental results confirm the effectiveness of the proposed method.<>
{"title":"Digital signal processing method for multilayered media thickness measurement","authors":"C. Delebarre, C. Bruneel, P. Miquet","doi":"10.1109/ULTSYM.1988.49533","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49533","url":null,"abstract":"An ultrasonic thickness measurement system for the 20- to 110- mu m range has been developed for thin paint layers on metallic or nonmetallic substrates. In the case of a multilayered sample this system generally furnishes only the sum of the different thicknesses. Thus, a digital signal-processing method has been developed to extract the different values of thickness from the power spectral density. This method is based on a power cepstrum analysis, defined as the Fourier transform of the logarithm power spectral density of the radio-frequency signal. This technique gives, in the case of three layers, the three thicknesses and their linear combinations. Experimental results confirm the effectiveness of the proposed method.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127577790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49526
M. Nikoonahad, K. Chin
Transverse flow measurement with high lateral resolution is demonstrated. The technique is based on collection and cross-correlation of signals scattered from two adjacent ultrasonic foci that are formed by a newly developed dual-beam acoustic lens. The lateral resolution for flow measurement is primarily determined by the separation of the focal spots. The authors present models and simulations based on both geometrical acoustics and diffraction that predict the behavior of the dual-beam lens. A 4.5-MHz flow measurement system has been constructed; the measured separation between the focal spots in this system is 2 mm, in good agreement with design and simulations. Preliminary results obtained from flow velocities in the 50- to 100-cm/s range in a 6-mm diameter tube are presented.<>
{"title":"Ultrasound transverse flow measurement with high lateral resolution","authors":"M. Nikoonahad, K. Chin","doi":"10.1109/ULTSYM.1988.49526","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49526","url":null,"abstract":"Transverse flow measurement with high lateral resolution is demonstrated. The technique is based on collection and cross-correlation of signals scattered from two adjacent ultrasonic foci that are formed by a newly developed dual-beam acoustic lens. The lateral resolution for flow measurement is primarily determined by the separation of the focal spots. The authors present models and simulations based on both geometrical acoustics and diffraction that predict the behavior of the dual-beam lens. A 4.5-MHz flow measurement system has been constructed; the measured separation between the focal spots in this system is 2 mm, in good agreement with design and simulations. Preliminary results obtained from flow velocities in the 50- to 100-cm/s range in a 6-mm diameter tube are presented.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117019871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49535
C. Soufflet, M. Fink
Random phase transducers were used to measure the attenuation of graphite epoxy composites of different porosity. It is shown that the random phase transducer allows attenuation estimation from the speckle noise coming from the sample volume. This technique is compared with the spatial compounding technique. Flaw detection is also performed with random phase transducers, and it is shown that specular reflector echoes are enhanced, compared with scattering noise, with this type of transducer.<>
{"title":"Attenuation measurement and flaw detection in graphite epoxy composites with random phase transducers","authors":"C. Soufflet, M. Fink","doi":"10.1109/ULTSYM.1988.49535","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49535","url":null,"abstract":"Random phase transducers were used to measure the attenuation of graphite epoxy composites of different porosity. It is shown that the random phase transducer allows attenuation estimation from the speckle noise coming from the sample volume. This technique is compared with the spatial compounding technique. Flaw detection is also performed with random phase transducers, and it is shown that specular reflector echoes are enhanced, compared with scattering noise, with this type of transducer.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117273948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-10-02DOI: 10.1109/ULTSYM.1988.49518
P. Lewin, M. Schafer, J. Gilmore
Extracorporeal shock wave lithotripsy (ESWL) has recently become the preferred procedure for the treatment of urinary and gall bladder stones. The device used in this treatment generates acoustic shock waves which are focused onto the stone, causing it to disintegrate. Interest in studying the properties of the shock waves quantitatively has intensified, since it is believed that the acoustic shock wave parameters, such as rise time, peak positive and peak negative pressure amplitudes, and frequency content, may influence the treatment's efficiency. In the present work the authors describe the evaluation of several piezoelectric materials and design configurations for their applicability to quantitative shock wave measurement. Preliminary experimental results indicate that PVDF (polyvinylidene fluoride) polymer sensors with a low acoustic impedance backing have the greatest potential as shock wave sensors.<>
{"title":"Ultrasonic probes for shock wave measurements","authors":"P. Lewin, M. Schafer, J. Gilmore","doi":"10.1109/ULTSYM.1988.49518","DOIUrl":"https://doi.org/10.1109/ULTSYM.1988.49518","url":null,"abstract":"Extracorporeal shock wave lithotripsy (ESWL) has recently become the preferred procedure for the treatment of urinary and gall bladder stones. The device used in this treatment generates acoustic shock waves which are focused onto the stone, causing it to disintegrate. Interest in studying the properties of the shock waves quantitatively has intensified, since it is believed that the acoustic shock wave parameters, such as rise time, peak positive and peak negative pressure amplitudes, and frequency content, may influence the treatment's efficiency. In the present work the authors describe the evaluation of several piezoelectric materials and design configurations for their applicability to quantitative shock wave measurement. Preliminary experimental results indicate that PVDF (polyvinylidene fluoride) polymer sensors with a low acoustic impedance backing have the greatest potential as shock wave sensors.<<ETX>>","PeriodicalId":263198,"journal":{"name":"IEEE 1988 Ultrasonics Symposium Proceedings.","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122451520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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