1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027)最新文献_第3页

Transversely coupled resonator filters 横向耦合谐振器滤波器

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849347

G. Martin

{"title":"Transversely coupled resonator filters","authors":"G. Martin","doi":"10.1109/ULTSYM.1999.849347","DOIUrl":"https://doi.org/10.1109/ULTSYM.1999.849347","url":null,"abstract":"Transversely Coupled Resonator Filters (TCRFs) have become an important type of low-loss filters with narrow bandwidth. Their basic layout consists of two one-port resonators arranged acoustically in parallel. Therefore a mechanism that couples both original resonators with each other is necessary. In today's TCRFs, this coupling is implemented by the waveguide effect. A brief description of the historical background is given. The most important steps were MSC, IDT and U-path coupled resonator filters, strip, slot wave-guides and grating waveguides. In the nineties, modeling goes different ways. On the one hand, plane-wave parameters are used for calculating the properties of waveguide modes. To do this, the stack-matrix approach or a conventional eigenmode analysis is applied. On the other hand, the COM theory plays an important role. For this, the COM parameters for the two fundamental waveguide modes are determined experimentally and put into the TCRF analysis. In recent years, new design features were suggested for widening the bandwidth of TCRFs without changing the waveguide parameters. In this connection, the utilization of higher modes, the principle of combining waveguide and cavity modes and the waveguide coupling of resonators with different properties are considered in more detail. Modeling as well as experimental results are presented. Finally, the advantages and disadvantages of TCRFs are discussed.","PeriodicalId":339424,"journal":{"name":"1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116530795","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}

引用次数: 9

Simulation and experimental characterization of a 2-D, 3-MHz capacitive micromachined ultrasonic transducer (CMUT) array element 二维，3mhz电容式微机械超声换能器(CMUT)阵列元件的仿真与实验表征

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849200

O. Oralkn, X. Jin, F. Degertekin, B. Khuri-Yakub

引用次数: 9

Measurement of acoustic resonance width via the inverse Fourier transform of the Breit-Wigner form 通过布雷特-维格纳形式的傅里叶反变换测量声共振宽度

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849516

D. Serge, R. Pascal, I. Jean-Louis

引用次数: 0

Numerical investigation of PSAW propagation in waveguides 波导中PSAW传播的数值研究

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849388

A. Ronnekleiv

引用次数: 1

Update of two dimensional arrays for real time volumetric and real time intracardiac imaging 更新二维阵列用于实时容积和实时心内成像

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849216

E. Light, J. Fiering, P. Hultman, W. Lee, S.W. Smith

{"title":"Update of two dimensional arrays for real time volumetric and real time intracardiac imaging","authors":"E. Light, J. Fiering, P. Hultman, W. Lee, S.W. Smith","doi":"10.1109/ULTSYM.1999.849216","DOIUrl":"https://doi.org/10.1109/ULTSYM.1999.849216","url":null,"abstract":"The authors have previously described 2-D array transducers with up to several thousand elements operating at frequencies between 2.5 and 5.0 MHz for real time volumetric imaging. Lately, there has been interest in developing catheter based intracardiac imaging systems to aid in the precise tracking of anatomical features and intracardiac devices for improved diagnoses and therapies. The authors constructed several arrays for real time intracardiac volumetric imaging based upon 2 different designs; a 13/spl times/11=143 element 5.0 MHz 2-D array for side scanning applications, and a 10/spl times/10=100 element 7.0 MHz 2-D array for side scanning applications. The 5.0 MHz array fits into a 12 French (3.8 mm OD) catheter and the 7.0 MHz transducer is designed to fit into a 9 French (2.9 mm OD) catheter. The authors also constructed 2 transducers for transthoracic imaging; a 40/spl times/40 5.0 MHz 2-D array, and a 40/spl times/40 7.0 MHz 2-D array. The -6 dB fractional bandwidths for the transducers varied from 27% to 67%. All the transducers were constructed on a 6 layer polyimide interconnect. Both transthoracic and intracardiac volumetric images of ultrasound phantoms and animal models have been obtained using the Duke University real time volumetric imaging system which is capable of generating multiple planes at any desired angle and depth within a pyramidal volume.","PeriodicalId":339424,"journal":{"name":"1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122993907","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}

引用次数: 18

Measuring the effects of ultrasound on contrast agents 测量超声对造影剂的影响

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849336

S. Podell, Brent Golec, Rolf Lohnnann

{"title":"Measuring the effects of ultrasound on contrast agents","authors":"S. Podell, Brent Golec, Rolf Lohnnann","doi":"10.1109/ULTSYM.1999.849336","DOIUrl":"https://doi.org/10.1109/ULTSYM.1999.849336","url":null,"abstract":"In vitro acoustic studies generally assume that known and reproducible quantities of contrast media are being evaluated, without need for agent retesting after dilution and handling. This assumption is incorrect, because duration of ultrasound contrast is substantially reduced by dilution of encapsulated, gas-filled agents into gas-poor solutions. Contrast agent persistence is enhanced and diffusive gas loss is slowed, but not eliminated, by filling microspheres with core gases having lower aqueous solubility. Since diffusive gas loss promotes safe elimination of gas bubbles in vivo, it is a desirable property that may prove unavoidable for commercial contrast agents. For non-encapsulated contrast agents containing emulsified perfluorocarbon liquids, exposure to threshold levels of ultrasound energy increased the dose of available contrast, by causing superheated liquid droplets to boil and form new microbubbles. This sudden activation threshold was not observed in encapsulated microsphere formulations, where the same perfluorocarbon was converted to vapor phase prior to insonation. These findings show that effective contrast agent doses can rapidly increase or decrease under conditions commonly used for in vitro acoustic testing. To avoid potential misinterpretation of experimental results, the effects of ultrasound independent factors on contrast agent stability need to be carefully considered.","PeriodicalId":339424,"journal":{"name":"1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117033957","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}

引用次数: 2

Intermediate frequency SAW filters for mobile phone application in Japanese markets 中频SAW滤波器在日本市场的手机应用

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849414

Y. Yamamoto, H. Kawahara, N. Sakairi, Y. Takahashi, R. Kajihara, T. Tsuda, S. Yoshimoto

引用次数: 5

New aspects for investigation of carrier transition through deep levels in GaAs by a piezoelectric photoacoustic technique 利用压电光声技术研究砷化镓深层载流子跃迁的新方面

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849478

A. Fukuyama, M. Iwamoto, Y. Akashi, T. Ikari, M. Suemitsu

引用次数: 0

Nonlinear scatter from Sonazoid Sonazoid的非线性散射

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849320

L. Hoff, T. Johansen

引用次数: 3

2D and 3D models for the cross-talk modeling in acoustic devices: a fast-MoM approach 声学器件串扰建模的二维和三维模型:一种快速mom方法

1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027) Pub Date : 1999-10-17 DOI: 10.1109/ULTSYM.1999.849383

A. Baghai-Wadji

{"title":"2D and 3D models for the cross-talk modeling in acoustic devices: a fast-MoM approach","authors":"A. Baghai-Wadji","doi":"10.1109/ULTSYM.1999.849383","DOIUrl":"https://doi.org/10.1109/ULTSYM.1999.849383","url":null,"abstract":"Scattering of transverse-electric or magnetic plane waves on infinitely long and ideally conductive strips and bends has been treated thoroughly quite long ago. Also, scattering of electromagnetic waves on rectangular bent plates has been the subject of research. Furthermore, wires in the vicinity of plates or bends, and wires attached to these structures have been investigated. The analyses have been performed by applying Harrington's method of moments (MoM). However, the design of even “canonical structures” can become quite challenging both in terms of computational resources and the accuracy: The calculations have to be repeated when any of problems' parameters e.g. frequency, bent angle, dimensions of the strips or plates or wires changes. In this paper we reconsider these problems for two reasons. First, they well may serve as models for 2D and 3D cross-talk modeling in acoustic devices, and there have great practical significance. Second, we treat these problems to point out the shortcomings of the conventional MoM, and to sketch how the newly proposed Fast-MoM technique eliminates them. In previous works we had applied the Fast-MoM to vector fields in flat surface problems, and to scalar fields in geometries with perpendicular boundaries. The present discussion shows how these geometric restrictions can be removed by introducing a local coordinate system.","PeriodicalId":339424,"journal":{"name":"1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129543146","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}

引用次数: 0