Pub Date : 1995-11-07DOI: 10.1109/ULTSYM.1995.495806
R. Johnson
Crosscoupling can occur over many different paths in ultrasound arrays. This paper deals with the problem of analyzing broadband crosscoupling data to determine the various paths and their relative importance. The key element is filtering in wavenumber-frequency space.
{"title":"Crosscoupling analysis for wideband arrays","authors":"R. Johnson","doi":"10.1109/ULTSYM.1995.495806","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495806","url":null,"abstract":"Crosscoupling can occur over many different paths in ultrasound arrays. This paper deals with the problem of analyzing broadband crosscoupling data to determine the various paths and their relative importance. The key element is filtering in wavenumber-frequency space.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"15 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133008677","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495536
M. Hikata, N. Shibagaki, K. Asai, K. Sakiyama, A. Sumioka
New filters used in an antenna duplexer which is applied to GHz-band digital cellular radios were developed. Taking 1.5 GHz PDC, we have achieved low insertion losses of 0.8 and 1.6 dB for T1 and R1 filters, respectively. The developed duplexer is 1.4/spl times/0.6/spl times/0.2 cm/sup 3/, several-time smaller than a conventional dielectric-filter duplexer. It also satisfied all required specifications and provided sufficient power-handling capabilities.
{"title":"New miniature SAW antenna duplexer used in GHz-band digital mobile cellular radios","authors":"M. Hikata, N. Shibagaki, K. Asai, K. Sakiyama, A. Sumioka","doi":"10.1109/ULTSYM.1995.495536","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495536","url":null,"abstract":"New filters used in an antenna duplexer which is applied to GHz-band digital cellular radios were developed. Taking 1.5 GHz PDC, we have achieved low insertion losses of 0.8 and 1.6 dB for T1 and R1 filters, respectively. The developed duplexer is 1.4/spl times/0.6/spl times/0.2 cm/sup 3/, several-time smaller than a conventional dielectric-filter duplexer. It also satisfied all required specifications and provided sufficient power-handling capabilities.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130606613","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495571
D. P. Morgan
This paper presents a new method for modelling SAW transducers with internal reflections, such as single-electrode transducers and various types of SPUDT. In the past the main method for analysing these transducers has been the coupled-mode (COM) analysis. The latter is approximate mainly because it represents the transducer (which has a discrete nature) in terms of smoothly-varying quantities governed by differential equations; also the COM is not easily related to the transducer physics. Other theoretical approaches, based on the physics, are more accurate and justifiable, but are usually inconvenient and time-consuming to compute. The Reflective Array Model (RAM) presented here gives a method more accurate and better justified than the COM, while retaining the feature of computational convenience. Reflections are analysed by a cascading technique which gives the acoustic scattering with full accuracy even if the electrode reflection coefficient is large. Transduction analysis is based on the quasi-static method used for non-reflecting transducers. Because of its derivation from the electrostatic solution, this method is very accurate, giving for example correct harmonic responses and correctly modelling the effects of changing electrode width. In contrast to COM, the RAM is accurate for short transducers and for wide analysis bands, it can give correct harmonic responses and it easily analyses weighted transducers.
{"title":"Reflective array modelling for SAW transducers","authors":"D. P. Morgan","doi":"10.1109/ULTSYM.1995.495571","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495571","url":null,"abstract":"This paper presents a new method for modelling SAW transducers with internal reflections, such as single-electrode transducers and various types of SPUDT. In the past the main method for analysing these transducers has been the coupled-mode (COM) analysis. The latter is approximate mainly because it represents the transducer (which has a discrete nature) in terms of smoothly-varying quantities governed by differential equations; also the COM is not easily related to the transducer physics. Other theoretical approaches, based on the physics, are more accurate and justifiable, but are usually inconvenient and time-consuming to compute. The Reflective Array Model (RAM) presented here gives a method more accurate and better justified than the COM, while retaining the feature of computational convenience. Reflections are analysed by a cascading technique which gives the acoustic scattering with full accuracy even if the electrode reflection coefficient is large. Transduction analysis is based on the quasi-static method used for non-reflecting transducers. Because of its derivation from the electrostatic solution, this method is very accurate, giving for example correct harmonic responses and correctly modelling the effects of changing electrode width. In contrast to COM, the RAM is accurate for short transducers and for wide analysis bands, it can give correct harmonic responses and it easily analyses weighted transducers.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130909405","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495749
T. Uchida, T. Suzuki, S. Shiokawa
Fluid motion due to high intensity sound is known as acoustic streaming. These flows are generated around obstacles immersed in sound or near oscillating bodies. Boundary streamings occur near the surface of a body in a sound field. In particular, streaming excited by SAW (surface acoustic waves) results in a slender jet. We investigated this streaming theoretically and experimentally. We applied the acoustic streaming theory and SAW transfer theory to the streaming excited by SAW.
{"title":"Investigation of acoustic streaming excited by surface acoustic waves","authors":"T. Uchida, T. Suzuki, S. Shiokawa","doi":"10.1109/ULTSYM.1995.495749","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495749","url":null,"abstract":"Fluid motion due to high intensity sound is known as acoustic streaming. These flows are generated around obstacles immersed in sound or near oscillating bodies. Boundary streamings occur near the surface of a body in a sound field. In particular, streaming excited by SAW (surface acoustic waves) results in a slender jet. We investigated this streaming theoretically and experimentally. We applied the acoustic streaming theory and SAW transfer theory to the streaming excited by SAW.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127967644","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495736
F. Levassort, D. Certon, G. Feuillard, F. Patat, M. Lethiecq
A model is advanced for 0-3 piezocomposites based on a generalisation of series and parallel analysis by a matrix method. The effective electroelastic moduli are predicted to deduce ultrasonic characteristics such as electromechanical coupling factor or longitudinal velocity. Particular cases are studied, such as 1-3 connectivity where Smith's results (1991) are obtained, due to the taking into account of mixed terms which introduce the effective anisotropy of the material. The effects of the polymer elastic stiffness on the properties of the 0-3 composites are also addressed and show that, for a given volume fraction, a stiff polymer is preferred to obtain a higher electromechanical coupling factor.
{"title":"Calculation scheme for electroelastic moduli of 0-3 piezocomposites","authors":"F. Levassort, D. Certon, G. Feuillard, F. Patat, M. Lethiecq","doi":"10.1109/ULTSYM.1995.495736","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495736","url":null,"abstract":"A model is advanced for 0-3 piezocomposites based on a generalisation of series and parallel analysis by a matrix method. The effective electroelastic moduli are predicted to deduce ultrasonic characteristics such as electromechanical coupling factor or longitudinal velocity. Particular cases are studied, such as 1-3 connectivity where Smith's results (1991) are obtained, due to the taking into account of mixed terms which introduce the effective anisotropy of the material. The effects of the polymer elastic stiffness on the properties of the 0-3 composites are also addressed and show that, for a given volume fraction, a stiff polymer is preferred to obtain a higher electromechanical coupling factor.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127978282","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495648
M. Zipparo, K. Shung, T. Shrout
The piezoelectric properties of PZT materials were experimentally studied as a function of grain size (0.2 to 2.5 /spl mu/m) at low frequencies (<20 MHz) and vs. frequency (10 to 100 MHz) for a single fine grain size (1.0 /spl mu/m). The piezoelectric properties were shown to decrease with decreasing grain size below 0.7 /spl mu/m. The fine grain size properties vs. frequency were compared to commercially available materials. The new fine grain materials were found to be superior to commercial materials at very high frequencies. Also, it was possible to construct resonators of the new ceramics at much higher frequencies than was possible for the conventional materials.
{"title":"Piezoelectric properties of fine grain PZT materials","authors":"M. Zipparo, K. Shung, T. Shrout","doi":"10.1109/ULTSYM.1995.495648","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495648","url":null,"abstract":"The piezoelectric properties of PZT materials were experimentally studied as a function of grain size (0.2 to 2.5 /spl mu/m) at low frequencies (<20 MHz) and vs. frequency (10 to 100 MHz) for a single fine grain size (1.0 /spl mu/m). The piezoelectric properties were shown to decrease with decreasing grain size below 0.7 /spl mu/m. The fine grain size properties vs. frequency were compared to commercially available materials. The new fine grain materials were found to be superior to commercial materials at very high frequencies. Also, it was possible to construct resonators of the new ceramics at much higher frequencies than was possible for the conventional materials.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131698132","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495652
H. Ledbetter, M. Dunn
Considering two-phase materials, we focus on the relationship between microstructure and physical properties, especially elastic constants. Microstructure includes occlusion concentration, orientation, shape, size, and distribution. Isotropic materials possess two independent elastic constants; orthotropic materials, nine; we emphasize the need to determine the complete elastic-constant tensor. We review principally three measurement methods: pulse-echo, rod-resonance, and acoustic-resonance spectroscopy. We show results for SiC/sub p//Al, mullite/sub p//Al, graphite/sub p//ferrite (cast iron), voids/Ti, B/sub f//Al, graphite/sub f//Al, SiC/sub sf//Al, epoxy/Al laminate. For some cases, we show the elastic constant's imaginary part: attenuation or internal friction. We emphasize combining measurements with modeling.
{"title":"Microstructure and elastic-constant measurements of two-phase materials","authors":"H. Ledbetter, M. Dunn","doi":"10.1109/ULTSYM.1995.495652","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495652","url":null,"abstract":"Considering two-phase materials, we focus on the relationship between microstructure and physical properties, especially elastic constants. Microstructure includes occlusion concentration, orientation, shape, size, and distribution. Isotropic materials possess two independent elastic constants; orthotropic materials, nine; we emphasize the need to determine the complete elastic-constant tensor. We review principally three measurement methods: pulse-echo, rod-resonance, and acoustic-resonance spectroscopy. We show results for SiC/sub p//Al, mullite/sub p//Al, graphite/sub p//ferrite (cast iron), voids/Ti, B/sub f//Al, graphite/sub f//Al, SiC/sub sf//Al, epoxy/Al laminate. For some cases, we show the elastic constant's imaginary part: attenuation or internal friction. We emphasize combining measurements with modeling.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128784534","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495534
J. Yin, D. Zhang, P. Wu, J. Yu, Y. Li
In this work we report a novel architecture for an harmonic filter with multi-track structure. The first example presented is a three-track structure. The displacement between two adjacent tracks is shifted /spl lambda//sub 0//6, where /spl lambda//sub 0/ is the wavelength at the fundamental frequency. The phase of the IDT in the middle track is inverse to that of the IDT's in the other two. Therefore, signals are cancelled at the fundamental frequency while enhanced at the third harmonic. For reducing the insertion loss of filters, the second example shown is a multi-track structure with a SPUDT transducer in each track. SPUDTs consist of third harmonic IDTs with /spl lambda//sub 0//8 width and strips with /spl lambda//sub 0//6 width as reflection arrays. Experimental results show that the sidelobe rejection is larger than 45 dB and fundamental response can be suppressed under -40 dB compared with the third harmonic. A filter at 1.4 GHz with an electrode width larger than 1 /spl mu/m on Y128/spl deg/X LiNbO/sub 3/ is also shown.
{"title":"Novel architecture of harmonic filter","authors":"J. Yin, D. Zhang, P. Wu, J. Yu, Y. Li","doi":"10.1109/ULTSYM.1995.495534","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495534","url":null,"abstract":"In this work we report a novel architecture for an harmonic filter with multi-track structure. The first example presented is a three-track structure. The displacement between two adjacent tracks is shifted /spl lambda//sub 0//6, where /spl lambda//sub 0/ is the wavelength at the fundamental frequency. The phase of the IDT in the middle track is inverse to that of the IDT's in the other two. Therefore, signals are cancelled at the fundamental frequency while enhanced at the third harmonic. For reducing the insertion loss of filters, the second example shown is a multi-track structure with a SPUDT transducer in each track. SPUDTs consist of third harmonic IDTs with /spl lambda//sub 0//8 width and strips with /spl lambda//sub 0//6 width as reflection arrays. Experimental results show that the sidelobe rejection is larger than 45 dB and fundamental response can be suppressed under -40 dB compared with the third harmonic. A filter at 1.4 GHz with an electrode width larger than 1 /spl mu/m on Y128/spl deg/X LiNbO/sub 3/ is also shown.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125498045","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495775
K. Masuda, K. Ishihara, T. Nagakura, T. Furukawa, H. Nishihara
The authors visualized the elasticity and viscosity of the common carotid artery noninvasively. The elastic index was calculated from the instantaneous velocity of the artery wall and continuous blood pressure. The instantaneous velocity was calculated from processing time series echograms recorded by high-frame-rate echography. Blood pressure was measured by a noninvasive sphygmomanometer using a cuff wound on the arm. The transition of velocity was related to blood pressure. Drawing pressure-velocity curve, elasticity and viscosity of carotid artery could be classified from the shape of the curve. In a young elastic artery, the curve was revealed to be similar to a circle. In a proportion of older arteries, the shape of the curve became flattened out. From the amplitude ratio of pressure and velocity, the elasticity and viscosity of an artery could be estimated.
{"title":"Elucidation of viscoelasticity of common carotid artery from time series echograms recorded by high-frame-rate echography","authors":"K. Masuda, K. Ishihara, T. Nagakura, T. Furukawa, H. Nishihara","doi":"10.1109/ULTSYM.1995.495775","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495775","url":null,"abstract":"The authors visualized the elasticity and viscosity of the common carotid artery noninvasively. The elastic index was calculated from the instantaneous velocity of the artery wall and continuous blood pressure. The instantaneous velocity was calculated from processing time series echograms recorded by high-frame-rate echography. Blood pressure was measured by a noninvasive sphygmomanometer using a cuff wound on the arm. The transition of velocity was related to blood pressure. Drawing pressure-velocity curve, elasticity and viscosity of carotid artery could be classified from the shape of the curve. In a young elastic artery, the curve was revealed to be similar to a circle. In a proportion of older arteries, the shape of the curve became flattened out. From the amplitude ratio of pressure and velocity, the elasticity and viscosity of an artery could be estimated.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"846 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123295247","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 : 1995-11-07DOI: 10.1109/ULTSYM.1995.495560
A. Pohl, C. Posch, F. Seifert, L. Reindl
We present a system for fast chirp-transform spectrum analysis for spectrum monitoring of frequency hopped spread spectrum signals or for spectrometry in chemistry etc. An elastic SAW convolver is used for fast realtime signal processing with high time-bandwidth product (TB). Using a convolver with TB=2650 we achieve a resolution of 125 kHz over 80 MHz bandwidth. The implementation of the presented system required some new concepts for the generation of the RF signals and weighting. The system showed satisfactory performance over a wide range of realtime signal analysis applications.
{"title":"Wideband compressive receiver with SAW convolver","authors":"A. Pohl, C. Posch, F. Seifert, L. Reindl","doi":"10.1109/ULTSYM.1995.495560","DOIUrl":"https://doi.org/10.1109/ULTSYM.1995.495560","url":null,"abstract":"We present a system for fast chirp-transform spectrum analysis for spectrum monitoring of frequency hopped spread spectrum signals or for spectrometry in chemistry etc. An elastic SAW convolver is used for fast realtime signal processing with high time-bandwidth product (TB). Using a convolver with TB=2650 we achieve a resolution of 125 kHz over 80 MHz bandwidth. The implementation of the presented system required some new concepts for the generation of the RF signals and weighting. The system showed satisfactory performance over a wide range of realtime signal analysis applications.","PeriodicalId":268177,"journal":{"name":"1995 IEEE Ultrasonics Symposium. Proceedings. An International Symposium","volume":"146 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123365389","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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