2009 IEEE International Ultrasonics Symposium最新文献

{"title":"Estimation of mechanical properties of arteries and soft tubes using shear wave speeds","authors":"M. Bernal, M. Urban, J. Greenleaf","doi":"10.1109/ULTSYM.2009.5441409","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441409","url":null,"abstract":"Arterial elasticity has gained importance in the past few decades as a predictor of cardiovascular diseases and mortality [1]. We propose a noninvasive technique using ultrasound radiation force and measurement of shear wave speed to calculate the mechanical properties of soft tubes and arteries noninvasively. To validate the technique we made three urethane tubes with different Young's moduli, tested the tubes and used the measured tube wall's shear wave speed and the modified Moens-Korteweg equation to estimate the Young's moduli. Samples of the same material were mechanically tested to compare the results from our technique. Excised carotid arteries from a pig were used to study the applicability of our method in soft tissues. Both the tubes and the arteries were embedded in gelatin to simulate the soft tissue surrounding the arteries, and pressurized using a column of water. The results from the tubes were in very good agreement with the mechanical testing, and the shear wave speed did not seem to change very much with change in transmural pressure. On the other hand, the excised arteries showed an increase in shear wave velocity with pressure and an increase in the Young's modulus. The technique we present here showed to be in good agreement with mechanical testing which gives us confidence to think that it can be applied in the study of arteries in vivo. Efforts towards implementing this technique in a clinical scanner are underway.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129009997","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}

{"title":"Influence of packaging atmospheres on the durability of high-temperature SAW sensors","authors":"J. Bardong, G. Bruckner, M. Kraft, R. Fachberger","doi":"10.1109/ULTSYM.2009.5441557","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441557","url":null,"abstract":"Surface acoustic wave (SAW) devices are a technology of choice for passive, radio-interrogable sensor applications operating under extreme conditions. Suitably designed SAW devices can withstand e.g. temperatures exceeding 400°C. At high temperatures (HT), thermal energies reach values corresponding to the activation energies of reactions between gas components and the crystal's substrate elements and/or the metallisation elements, respectively. Thus, the atmosphere in the hermetic packaging becomes a crucial factor for the SAW device's stability. This work investigates the influence of various potential packaging atmospheres on SAW devices at temperatures up to 650°C. The SAW test structures consist of two delay lines with different lengths, which have been processed with Pt - based thin films. Substrate materials were either langasite (LGS), lithium niobate (LN) or stochiometric lithium niobate (sLN). The devices were annealed in a tube oven equipped with a HT-stable radio frequency (RF) measurement system in different atmospheres at several temperature levels up to 650°C. Afterwards, the SAW surfaces were characterised microscopically.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130502386","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}

{"title":"A model for radial modes in a piezoelectric disc exhibiting non-uniform polarization: Application to a bi-frequency transducer, method design, simulation and experiments","authors":"H. Calás, L. D. Pérez-Fernández, E. Moreno, J. Eiras, A. Ramos","doi":"10.1109/ULTSYM.2009.5442078","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5442078","url":null,"abstract":"Piezoelectric ceramics are widely used in a variety of devices such as ultrasonic transducers, piezoelectric transformers, piezoelectric step motors and frequency control circuits. Uniformly poled piezoelectric discs (UPDs) are the simplest configurations used for transducers, and so their vibration characteristics are well known. On the other hand, some authors have employed non-uniformly poled discs (NUPDs) in applications like ultrasonic beam control. However, theoretical NUPDs behavior is still poorly studied. In this contribution, we present a model for radial modes description in a NUPD disc.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130525657","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}

{"title":"Non-scanning measurement of local curvature with an ultrasound annular array","authors":"M. Lenz, J. Sorber, E. Kuhnicke, G. Gerlach, T. Rodig, H. Trier","doi":"10.1109/ULTSYM.2009.5441830","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441830","url":null,"abstract":"The paper studies a novel approach for measuring local object curvature radii without scanning. Instead of scanning, an ultrasound annular array is used, and the phase and amplitude differences on the different receiver rings, which contain the curvature information, are used to determine the object curvature radius. Two evaluation methods are compared: One method is based on changing the focus of the transducer, whereas the other one is based on measuring phase differences between several receiving channels.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126684829","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}

{"title":"Inducing rapid fluid flows in microchannels with surface acoustic waves","authors":"M. Tan, L. Yeo, J. Friend","doi":"10.1109/ULTSYM.2009.5441547","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441547","url":null,"abstract":"We investigate uniform fluid and mixing flows with linear speeds up to 1–10 mm/s, actuated by surface acoustic waves. Under strong acoustic excitation, transition from uniform to oscillatory mixing flow occurs when the width of the channel increases beyond one acoustic wavelength of sound in the fluid λf . In this high velocity regime, particles of one micrometer in diameter suspended in aqueous solution are observed to follow the streamlines. Under weak acoustic excitation, particles aligning into equally-spaced lines (with a separation of λf/2) due to the presence of acoustic standing waves across the channel and move slowly in the reverse direction due to the slow streaming. We developed a numerical model of the system that accounts for the acoustic streaming in the fluid with treatment of viscous and solid-fluid coupling effects, and the results qualitatively support the observed phenomena in the experiments.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130639731","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}

{"title":"High performance microwave acoustic components for mobile radios","authors":"F. M. Pitschi, J. Kiwitt, R. Koch, B. Bader, K. Wagner, R. Weigel","doi":"10.1109/ULTSYM.2009.5441550","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441550","url":null,"abstract":"Due to their outstanding characteristics acoustic components, such as SAW and - later on - also BAW filters, have been key components in wireless communication systems from their very beginning. Regarding mobile radio handsets the primary field of application of acoustic components has moved to the RF front-end sections. Here, with the increasing demand for WCDMA-FDD capable mobile phones, duplexers, which allow to separate the TX and RX paths while being simultaneously connected to the antenna, have become indispensable. Regarding the specifications of the different operating bands the requirements on form factors, pass band characteristics, attenuations of the other signals (TX, RX, GPS, WLAN, ...), and isolations make them high performance components requiring a sophisticated acoustic as well as electromagnetic design. Due to the tough requirements imposed on the duplexers in terms of, e.g., center frequencies, spacings of RX and TX bands, relative band widths, and shape factors, they also require application-specific acoustic structures. As a consequence, in contrast to standard filters, duplexers are highly optimized components using leading-edge technologies. In order to achieve the best balance of the characteristic properties of the acoustic structures regarding, for instance, their quality factors, pole-zero distances, and temperature coefficients, the manufacturing processes of the acoustic chips are designed for the specific applications. Furthermore, optimizing the electrical characteristics a co-design of package and acoustic chip is applied. In this paper we provide an overview of the different types of duplexers that have been the result of the focused specialization and optimization efforts. We classify them according to the type of acoustic structures, matching circuitry, and package being used. So far, purely SAW-based and BAW-based duplexers as well as hybrid duplexers using both SAW and BAW chips have been reported. Most of the matching circuitry is integrated in, for instance, an LTCC package using a distributed approach based on a ?/4 line or a lumped approach comprising coils and/or capacitors. Sometimes the matching circuitry is realized externally on the PCB. Furthermore, we present recent integration successes, i.e., duplexer inserts, allowing the seamless integration of duplexers into modules without drawbacks on performance or module thickness.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"145 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123980183","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}

{"title":"Patterning of 30MHz ultrasonic Fresnel zone plate by laser poling of PVDF-TrFE film","authors":"H. Yanagida, Y. Tamura, Tatsuhisa Takahashi","doi":"10.1109/ULTSYM.2009.5441937","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441937","url":null,"abstract":"This paper describes a novel approach to construct Fresnel zone plate (FZP) transducers by laser poling of poly vinyliden fluoride-co- trifluoroethylene films. The patterning of polarization was confirmed by measurement of pyroelectricity current. After this confirmation, the transducer was driven in the water bath and the spatial distribution of the sound pressure was measured. The directivity of the transducer was compared to the flat and concave transducers of same aperture size.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"4 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121003847","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}

{"title":"A novel equivalent circuit model for CMUTs","authors":"H. Kagan Oguz, S. Olçum, M. N. Senlik, A. Atalar, H. Koymen","doi":"10.1109/ULTSYM.2009.5441435","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441435","url":null,"abstract":"A nonlinear equivalent circuit for immersed transmitting capacitive micromachined ultrasonic transducers (CMUTs) is presented. The velocity profile across the CMUT surface maintains the same form over a wide frequency range. This property and the profile are used to model both the electromechanical conversion and the mechanical section. The model parameters are calculated considering the root mean square of the velocity distribution on the membrane surface as the through variable. The new model is compared with the FEM simulation results. The new model predicts the CMUT performance very accurately.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"34 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121154708","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}

{"title":"Novel ultrasonic motor using torsional/ longitudinal vibration","authors":"S. Bhargava, D. Greve, I. Oppenheim","doi":"10.1109/ULTSYM.2009.5441751","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441751","url":null,"abstract":"Longitudinal-torsional mode converters have greatly simplified the structure of ultrasonic motors using a combined torsional/ longitudinal vibration, making miniaturization more practical. A previous design of this type of motor used a multi-layer piezoelectric actuator. In this paper, we report on the performance of motors using wafer-type actuators. This motor design requires a reduced volume of piezoelectric material.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121340654","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}

{"title":"Study on the shallow underground imaging by the pulse compression method that considered frequency dependent attenuation","authors":"T. Sugimoto, H. Kawasaki","doi":"10.1109/ULTSYM.2009.5441998","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441998","url":null,"abstract":"Frequency dependent attenuation of chirp wave in shallow underground is measured at each frequencies and half width (axial resolution) is calculated by simulation using measurement data. And an exploration experiment is carried out to confirm the effect of the compensation of high frequency domain. From the simulation results, half width are smaller than 0.2m are obtained when Δf is more than 500Hz (800–300Hz linear down chirp, duration time 100ms). From the experimental results, compensation of high frequency domain are effective for high resolution underground image. And linear down chirp showed the best underground image in this case. And the axial resolution of underground image is the quite same as simulation.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121426747","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}