Abstract:
:In medical ultrasound imaging, two-dimensional (2-D) array transducers are desirable to implement dynamic focusing and phase aberration correction in two dimensions as well as volumetric imaging. Unfortunately, the small size of a 2-D array element results in a small clamped capacitance and a large electrical impedance near the resonance frequency. This results in poor signal-to-noise ratio (SNR) of the array elements. It has previously been demonstrated that transducers made from multilayer PZT ceramics have lower electrical impedance and greater SNR than comparable single layer elements. A simplified circuit model has been developed to optimize the SNR for multilayer ceramic (MLC) transducers. In this model, an electronic transmitter excites the array element and in the receive mode, the element drives a coaxial cable load terminated by a high impedance preamplifier. The transducer impedance is Zt/N2, where N is the number of piezoelectric layers. Maximum transmit signal is obtained when N = Ntx such that the transducer impedance, Zt/Ntx2, is matched to the source impedance. Maximum receive signal is obtained when N = Nrx such that the transducer impedance, Zt/Nrx2, is matched to the coaxial cable reactance. For maximum pulse-echo signal, the transducer should be designed with N = square root of Ntx Nrx, the geometric mean of Ntx and Nrx. Using this optimization technique, a 1.5-D array was designed with 3 layers for maximum pulse-echo SNR. Results of simulations from the simplified circuit analysis were consistent with those of the KLM model. The 3 layer array was fabricated as well as a single layer control array. The measured transmit signal and receive signal agreed with the simulation results.
journal_name
Ultrason Imagingjournal_title
Ultrasonic imagingauthors
Goldberg RL,Smith SWdoi
10.1177/016173469501700202subject
Has Abstractpub_date
1995-04-01 00:00:00pages
95-113issue
2eissn
0161-7346issn
1096-0910journal_volume
17pub_type
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460402600402
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journal_title:Ultrasonic imaging
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doi:10.1177/0161734613511232
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460302500201
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journal_title:Ultrasonic imaging
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doi:10.1177/0161734618815070
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734616689464
更新日期:2017-07-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173461003200103
更新日期:2010-01-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章,评审
doi:10.1177/0161734617692018
更新日期:2017-09-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469001200302
更新日期:1990-07-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469401600202
更新日期:1994-04-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460202400404
更新日期:2002-10-01 00:00:00
abstract::Sidelobe contribution from off-axis targets degrades image quality in a coherent array imaging system. In ultrasound imaging, focusing errors resulting from sound-velocity inhomogeneities in human tissue--also known as phase aberrations reduce the coherence of the received signals and elevate the sidelobe level. This ...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460502700205
更新日期:2005-04-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460002200201
更新日期:2000-04-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460903100303
更新日期:2009-07-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734616686746
更新日期:2017-05-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468500700402
更新日期:1985-10-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460302500303
更新日期:2003-07-01 00:00:00
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460202400202
更新日期:2002-04-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469902100303
更新日期:1999-07-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460402600101
更新日期:2004-01-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468901100301
更新日期:1989-07-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734615600167
更新日期:2016-07-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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更新日期:2020-11-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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更新日期:1997-01-01 00:00:00