Measuring signal quality in low power wearable ultrasound imaging

2021 ◽  
Vol 150 (4) ◽  
pp. A90-A90
Author(s):  
Samuel A. Acuña ◽  
Ahmed Bashatah ◽  
Parag V. Chitnis ◽  
Siddhartha Sikdar
2018 ◽  
Vol 65 (7) ◽  
pp. 829-833 ◽  
Author(s):  
Ji-Yong Jeong ◽  
Jae-Sung An ◽  
Sung-Jin Jung ◽  
Seong-Kwan Hong ◽  
Oh-Kyong Kwon

Author(s):  
Elizabeth Tarbox ◽  
Nima Akhlaghi ◽  
Ananya Dhawan ◽  
Paul Gammell ◽  
Parag Chitnis ◽  
...  

Biosensors ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 44 ◽  
Author(s):  
Shahriar Jamasb

Accurate and cost-effective integrated sensor systems for continuous monitoring of pH and blood gases continue to be in high demand. The capacity of ion-selective and Gas-sensitive field effect transistors (FETs) to serve as low-power sensors for accurate continuous monitoring of pH and blood gases is evaluated in the amperometric or current mode of operation. A stand-alone current-mode topology is employed in which a constant bias is applied to the gate with the drain current serving as the measuring signal. Compared with voltage-mode operation (e.g., in the feedback mode in ion-selective FETs), current-mode topologies offer the advantages of small size and low power consumption. However, the ion-selective FET (ISFET) and the Gas-sensitive FET (GasFET) exhibit a similar drift behavior, imposing a serious limitation on the accuracy of these sensors for continuous monitoring applications irrespective of the mode of operation. Given the slow temporal variation associated with the drift characteristics in both devices, a common post-processing technique that involves monitoring the variation of the drain current over short intervals of time can potentially allow extraction of the measuring signal in presence of drift in both sensor types. Furthermore, in the amperometric mode the static sensitivity of a FET-based sensor, given by the product of the FET transconductance and the sensitivity of the device threshold voltage to the measurand concentration, can be increased by adjusting the device design parameters. Increasing the sensitivity, while of interest in its own right, also enhances the accuracy of the proposed method. Rigorous analytical validation of the method is presented for GasFET operation in the amperometric mode. Moreover, the correction algorithm is verified experimentally using a Si3N4-gate ISFET operating in the amperometric mode to monitor pH variations ranging from 3.5 to 10.


Author(s):  
Hendri Lesmono ◽  
Khairi Budayawan ◽  
Yasdinul Huda

Digital Video Broadcasting via Satellite (DVB-S) is a communications that use a satellites as a repeater signal from the sender to the receiver. Because it uses the satellite as a repeater signal , then in the sender and receiver use a parabolic antenna type. The majority of the current parabolic antenna reflector color comes from the color of the material used reflector itself is gray, while the use of other types of color are rarely used be it a lighten color or darken color, in addition to use of the parabolic reflector antenna at this point, especially for the type of solid is very susceptible to corrosion or rust. So it is necessary to research on the influence of color on quality parabolic reflector antenna signal that produce either from a parabolic type of solid or mesh type.This type of experimental research, in this researchers informant trying to observe and manipulated object under control. Informant painting on the parabolic reflector antenna, measuring signal quality, signal strength and the value of C/N and then compare the results of measurements on each color parabolic reflector antenna. Instruments used by informant is a parabolic antenna, Low Noise Block (LNB)and satellite meter.The results showed that the color of a parabolic reflector antenna isinfluence on signal quality and strength of the signal that received by the receiver. The more bright colors that used in parabolic reflector antenna, more electromagnetic waves are reflected toward the LNB satellite dish antenna and vice versa which have an impact on increasing the quality of the received signal at the receiver. Painting parabolic reflector antenna other than as an attempt to prevent corrosion are also could to improve the quality of the signal, with a record of using colors that have been suggested. Color parabolic reflector antennas are recommended for applications DVB - S is a white and light blue


Author(s):  
Damian Cacko ◽  
Mateusz Walczak ◽  
Marcin Lewandowski

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