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An investigation of electro-optical 1/f noise reduction in an open-path tunable diode laser spectrometer.

Record Type:	Language materials, printed : Monograph/item
Title/Author:	An investigation of electro-optical 1/f noise reduction in an open-path tunable diode laser spectrometer./
Author:	Mahdi, Samira A.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2013,
Description:	184 p.
Notes:	Source: Dissertations Abstracts International, Volume: 75-06, Section: B.
Contained By:	Dissertations Abstracts International75-06B.
Subject:	Aerospace engineering. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3601565
ISBN:	9781303530128

An investigation of electro-optical 1/f noise reduction in an open-path tunable diode laser spectrometer.
Mahdi, Samira A.

An investigation of electro-optical 1/f noise reduction in an open-path tunable diode laser spectrometer. - Ann Arbor : ProQuest Dissertations & Theses, 2013 - 184 p.

Source: Dissertations Abstracts International, Volume: 75-06, Section: B.

Thesis (Ph.D.)--University of Arkansas at Little Rock, 2013.

This item must not be sold to any third party vendors.

A mobile spectrometer system has been designed to scan the near-surface atmosphere for ammonia gas over a wide range of distances (10 m to 1 Km). Since the system is designed for space applications, it needs to be small, light weight, and low power, which dictates the use of relatively low frequency measurement scans. The spectrometer uses a diode laser, which is subject to a large of electro-optical 1/f noise component at these low frequencies. In this work, digital signal processing techniques are developed to reduce the effects of 1/f noise in gas measurements. A Double Fast Fourier Transform-Based Filter (DFFT-BF) method is developed to maximize the measurement sensitivity of a low frequency Tunable Diode Laser Spectrometer (TDLS) system. The 1/f noise spectrum and the uncertainty in the wavelength of the diode laser emission due to 1/f frequency noise is investigated in both simulations and experiments. Also, measurements of ammonia gas using its 1543 nm absorption peak were performed using a sinusoidal waveform to drive the diode laser. A signal processing method is proposed that reduces the effects of electro-optical 1/f noise while keeping the measurement signal relatively constant. Measurements with different modulated waveforms are also examined, including a sawtooth with superimposed sine wave and a sinusoidal wave with a multiple step offset to drive the diode laser. In addition, the system is tested in outdoor measurements of ammonia gas concentrations. The results show that the DFFT-BF method reduces the effects of the 1/f noise in the measurement.

ISBN: 9781303530128Subjects--Topical Terms:

686400
Aerospace engineering.
Subjects--Index Terms:

Ammonia

An investigation of electro-optical 1/f noise reduction in an open-path tunable diode laser spectrometer.
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245 1 3 $a An investigation of electro-optical 1/f noise reduction in an open-path tunable diode laser spectrometer.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2013
300 $a 184 p.
500 $a Source: Dissertations Abstracts International, Volume: 75-06, Section: B.
500 $a Publisher info.: Dissertation/Thesis.
500 $a Advisor: Anderson, Gary.
502 $a Thesis (Ph.D.)--University of Arkansas at Little Rock, 2013.
506 $a This item must not be sold to any third party vendors.
520 $a A mobile spectrometer system has been designed to scan the near-surface atmosphere for ammonia gas over a wide range of distances (10 m to 1 Km). Since the system is designed for space applications, it needs to be small, light weight, and low power, which dictates the use of relatively low frequency measurement scans. The spectrometer uses a diode laser, which is subject to a large of electro-optical 1/f noise component at these low frequencies. In this work, digital signal processing techniques are developed to reduce the effects of 1/f noise in gas measurements. A Double Fast Fourier Transform-Based Filter (DFFT-BF) method is developed to maximize the measurement sensitivity of a low frequency Tunable Diode Laser Spectrometer (TDLS) system. The 1/f noise spectrum and the uncertainty in the wavelength of the diode laser emission due to 1/f frequency noise is investigated in both simulations and experiments. Also, measurements of ammonia gas using its 1543 nm absorption peak were performed using a sinusoidal waveform to drive the diode laser. A signal processing method is proposed that reduces the effects of electro-optical 1/f noise while keeping the measurement signal relatively constant. Measurements with different modulated waveforms are also examined, including a sawtooth with superimposed sine wave and a sinusoidal wave with a multiple step offset to drive the diode laser. In addition, the system is tested in outdoor measurements of ammonia gas concentrations. The results show that the DFFT-BF method reduces the effects of the 1/f noise in the measurement.
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650 4 $a Physics. $3 564049
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653 $a Laser diode
653 $a Methane
653 $a Noise reduction
653 $a Tdls
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710 2 $a University of Arkansas at Little Rock. $b Applied Science. $3 1148548
773 0 $t Dissertations Abstracts International $g 75-06B.
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792 $a 2013
793 $a English
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