Abstract
A set of prototype RF delay lines have been developed in order to meet the required bandwidth, delay accuracy, and delay range requirements for a previously developed 64 channel endoscopic phased array prototype. Each delay line is based on a planar PMN-32%PT pulse-echo transducer situated in a water bath, reflecting off a polished brass reflector. The pulse-echo transducers are mounted on individual in-house fabricated piezoelectric bimorphs, which are 'simply' supported. This creates an electronic delay time proportional to the distance between the single-element transducer and the reflecting surface in the water bath. When the physical length between the transducer and the reflecting surface is changed, the delay time also changes. A variable high voltage signal causes bimorph actuation and, in turn, the variable delays. The experimentally measured centre frequency and bandwidth for the pulse echo transducers was 45 MHz and 60% respectively. The pulse echo insertion loss without considering water attenuation or loss into the brass reflector was measured to be -20.8 dB, therefore one single low-noise amplifier with 20 dB gain was required for each delay line to have zero insertion loss. The signal-to-noise ratio was only decreased by 1.1dB with this amplifier in place. The total delay range measured by adjusting the bimorph voltage by +/- 80V was 1.4 μs, and the accuracy/repeatability of the pulse delay was less than 3ns. To date 16 channels of individually controlled parallel delays have been fabricated and the fabrication/testing of a full 64 channel system is ongoing.
Original language | English |
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Title of host publication | IEEE International Ultrasonics Symposium, IUS |
Publisher | IEEE Computer Society |
Pages | 2197-2200 |
Number of pages | 4 |
ISBN (Electronic) | 9781479970490 |
DOIs | |
Publication status | Published - Oct 20 2014 |
Event | 2014 IEEE International Ultrasonics Symposium, IUS 2014 - Chicago, United States Duration: Sept 3 2014 → Sept 6 2014 |
Publication series
Name | IEEE International Ultrasonics Symposium, IUS |
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ISSN (Print) | 1948-5719 |
ISSN (Electronic) | 1948-5727 |
Conference
Conference | 2014 IEEE International Ultrasonics Symposium, IUS 2014 |
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Country/Territory | United States |
City | Chicago |
Period | 9/3/14 → 9/6/14 |
Bibliographical note
Publisher Copyright:© 2014 IEEE.
ASJC Scopus Subject Areas
- Acoustics and Ultrasonics