Optical Homodyne Frequency Domain Reflectometer using an external cavity semiconductor laser /
An external cavity traveling-wave semiconductor ring laser with a narrow linewidth is used as a light source for building an Optical Homodyne Frequency Domain Reflectometer (OHFDR). The optical frequency of the laser is linearly chirped by an intracavity phase modulator. The Fresnel reflection and...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1995.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=742744451&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | An external cavity traveling-wave semiconductor ring laser with a narrow linewidth is used as a light source for building an Optical Homodyne Frequency Domain Reflectometer (OHFDR). The optical frequency of the laser is linearly chirped by an intracavity phase modulator. The Fresnel reflection and Rayleigh backscattered light from an optical fiber is mixed with a reference light to produce a RF signal. The frequency of the RF signal indicates the spatial position of the reflection. For a 10 km optical fiber measurement, a spatial resolution of 30 meters and a one-way dynamic range of 28 dB for Rayleigh backscattered light have been achieved. The theory of the OHFDR is also developed in this thesis. The theory predicts the performance of the OHFDR as a function of various operational parameters such as the round-trip time delay, the maximum sweep frequency, the sweep period, the laser linewidth, the resolution of the spectrum analyzer, and the input power level. Predictions of the theory are compared with measurements. Good agreements are obtained. |
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| Item Description: | Vita. "Major Subject: Elecrical Engineering". |
| Physical Description: | xi, 63 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |