Parametric beam-steering technique for acoustic waves with applications to signal processing

Sensors discussed are designed to register acoustic waves and micro deformations in ground. Sensor technology is based on phase modulation that occurs in optical fiber when it is influenced by outside mechanical disturbance. In our paper we consider two possible ways of registration this phase modulation: fiber optic interferometer and mode to mode interference. These methods can be incorporated with various signal processing technique to obtain maximum efficiency of fiber optic sensor under the certain conditions. It is well known that optical fibers are widely used to transmit high band signals for long distances. In this case fiber sensitivity to environmental disturbances is a bad thing. But from other side the disturbances change propagating light properties (intensity, phase, polarization, etc.). This changes can be registered in the output light and after appropriate signal processing will give information about the parameters of the outside influence on the fiber. This is an idea in brief how optical fibers can be used as physical parameters sensors.

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Signal processing using surface acoustic waves

IEEE Communications Magazine ◽

10.1109/mcom.1985.1092553 ◽

1985 ◽

Vol 23 (4) ◽

pp. 6-11 ◽

Cited By ~ 5

Author(s):

W. Shreve

Keyword(s):

Signal Processing ◽

Acoustic Waves ◽

Surface Acoustic Waves

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A Novel Faint Signal Processing Method for Sensitivity Improvement of Pump/Probe-Based LG/LD SAW Spectroscopy System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.301-303.188 ◽

2011 ◽

Vol 301-303 ◽

pp. 188-194

Author(s):

Mao Sen Bai ◽

Xing Fu ◽

Dante Dorantes ◽

Bao Yin Jin ◽

Xiao Tang Hu

Keyword(s):

Signal Processing ◽

Acoustic Waves ◽

Dead Zone ◽

Surface Acoustic Waves ◽

Processing Method ◽

Pump Probe ◽

Phase Lock ◽

Signal Processing Method ◽

Working Principle ◽

Spectroscopy System

A novel faint signal processing method based on phase-lock amplification principle is developed to enhance the sensitivity of pump/probe-based laser generated and laser detected surface acoustic waves (LG/LD SAW) spectroscopy system. This novel method involves a “dead zone” filter located before a common phase-lock amplification unit, which wipes off most of the noise stacked on SAW signal. This paper explored the working principle of this novel signal processing method based on the knowledge of the characteristics of the system noise and the signal. The experiment result shows that the detection system’s sensitivity has been dramatically improved by this new signal processing method.

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Measuring effective stiffness of Li-ion batteries via acoustic signal processing

Journal of Materials Chemistry A ◽

10.1039/d0ta05552b ◽

2020 ◽

Vol 8 (32) ◽

pp. 16624-16635 ◽

Cited By ~ 1

Author(s):

Wesley Chang ◽

Robert Mohr ◽

Andrew Kim ◽

Abhi Raj ◽

Greg Davies ◽

...

Keyword(s):

Signal Processing ◽

Acoustic Signal ◽

Acoustic Waves ◽

Sound Speed ◽

Effective Stiffness ◽

High Rate ◽

Li Ion Batteries ◽

Material Stiffness ◽

Li Ion

Accurate signal processing of acoustic waves is utilized to measure the intrinsic material stiffness of a layered cell stack and explore relationships between battery displacement, sound speed and stiffness during high rate cycling.

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Numerical Simulation of Enhanced Photoacoustic Generation and Wavefront Shaping by a Distributed Laser Array

Applied Sciences ◽

10.3390/app11209497 ◽

2021 ◽

Vol 11 (20) ◽

pp. 9497

Author(s):

Ruijie Hou ◽

Bin Xu ◽

Zhiying Xia ◽

Yang Zhang ◽

Weiping Liu ◽

...

Keyword(s):

Acoustic Waves ◽

Photoacoustic Imaging ◽

Signal To Noise Ratio ◽

Beam Steering ◽

Laser Pulses ◽

Laser Array ◽

Flexible Control ◽

Mechanical Waves ◽

Laser Induced Damage ◽

Array Generation

In photoacoustic imaging, the use of arrayed laser sources brings several advantages. Acoustic waves can be generated with flexible control of wavefronts, bringing functionality such as ultrasonic beam steering and focusing. The use of arrays reduces the optical intensity while increasing the strength of the ultrasonic wave, bringing the advantages of improved signal-to-noise ratio (SNR) while avoiding laser-induced damage. In this paper, we report a numerical model for studying the generation and shaping of acoustic wavefronts with laser arrays. The propagation of mechanical waves, photoacoustically generated by thermal expansion, is simulated and discussed in detail. In addition, a partially delayed distributed array is studied both theoretically and quantitatively. The developed model for wavefront control through time-delayed laser pulses is shown to be highly suited for the optimization of laser array generation schemes.

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