發(fā)布時(shí)間：2018-05-08 10:45

  本文選題：布里淵散射 + 瑞利散射�。� 參考：《華北電力大學(xué)》2017年碩士論文

【摘要】：本文介紹了分布式光纖傳感技術(shù)的發(fā)展背景和現(xiàn)狀,主要闡述了布里淵光時(shí)域分析(BOTDA)的研究現(xiàn)狀,論述了光纖中的布里淵散射特性,揭示了其與溫度和應(yīng)變的關(guān)系。分析了基于編碼的瑞利BOTDA的傳感理論及性能,并對(duì)編碼瑞利BOTDA實(shí)驗(yàn)系統(tǒng)進(jìn)行了研究與設(shè)計(jì)。首先針對(duì)編碼瑞利BOTDA系統(tǒng)中的編碼技術(shù)即格雷碼和Simplex(簡(jiǎn)稱S)碼技術(shù)進(jìn)行了簡(jiǎn)單介紹,分析其編解碼原理;深入研究格雷碼和S碼在瑞利BOTDA系統(tǒng)中的實(shí)現(xiàn)方法,并對(duì)編碼瑞利BOTDA系統(tǒng)的信噪比改善量進(jìn)行了理論分析和仿真驗(yàn)證。其次分析了基于雪崩光電二極管(APD)檢測(cè)和S編碼的瑞利BOTDA系統(tǒng)中的兩種噪聲,隨機(jī)散粒噪聲和熱噪聲。隨機(jī)散粒噪聲功率和信號(hào)功率有關(guān),而熱噪聲功率主要取決于APD光電檢測(cè)器的性能、與信號(hào)功率無(wú)關(guān)。由系統(tǒng)中與兩種噪聲相關(guān)的電流波動(dòng)的方差和S碼的編解碼規(guī)則可得編碼系統(tǒng)的均方誤差,由此推導(dǎo)了系統(tǒng)信噪比和編碼增益公式,并利用MATLAB進(jìn)行了仿真驗(yàn)證。最后設(shè)計(jì)了格雷碼瑞利BOTDA實(shí)驗(yàn)系統(tǒng),重點(diǎn)設(shè)計(jì)的部分是系統(tǒng)的編解碼部分。在設(shè)計(jì)編碼系統(tǒng)前先進(jìn)行了單脈沖編碼瑞利BOTDA系統(tǒng)的設(shè)計(jì)和測(cè)量。理論分析了受激布里淵散射(SBS)瞬態(tài)耦合波方程對(duì)非歸零(NRZ)碼和歸零(RZ)碼系統(tǒng)中聲波場(chǎng)幅度和布里淵增益的影響,進(jìn)行了NRZ和RZ的格雷碼瑞利BOTDA系統(tǒng)的實(shí)驗(yàn)研究。
[Abstract]:In this paper, the development background and present situation of distributed optical fiber sensing technology are introduced, the research status of Brillouin optical time domain analysis (BOTDA) is mainly described, the Brillouin scattering characteristics in optical fiber are discussed, and the relationship between Brillouin scattering and temperature and strain is revealed. The sensing theory and performance of coded Rayleigh BOTDA are analyzed, and the experimental system of coded Rayleigh BOTDA is studied and designed. Firstly, this paper introduces the coding technology of Rayleigh BOTDA system, that is, Graycode and Simplexcode, analyzes the encoding and decoding principle, and deeply studies the realization method of Gray-code and S-Code in Rayleigh BOTDA system. The improvement of signal-to-noise ratio of coded Rayleigh BOTDA system is analyzed theoretically and verified by simulation. Secondly, two kinds of noise, random shot noise and thermal noise, in Rayleigh BOTDA system based on avalanche photodiode detection and S-coding are analyzed. The random shot noise power is related to the signal power, while the thermal noise power mainly depends on the performance of the APD photodetector and is independent of the signal power. The mean square error of the coding system can be obtained from the variance of the current fluctuation associated with two kinds of noise and the encoding and decoding rules of the S-code. The formulas of the SNR and the coding gain of the system are derived and verified by MATLAB simulation. Finally, a Gray-Rayleigh BOTDA experimental system is designed, the key part of which is the coding and decoding part of the system. The design and measurement of monopulse coded Rayleigh BOTDA system are carried out before the design of coding system. The effects of transient coupled wave equations of stimulated Brillouin scattering (SBS) on the amplitude of acoustic field and Brillouin gain in non-return-to-zero (NRZ) and return-to-zero (RZ) codes are analyzed theoretically. The experimental study of Gray-Code-Rayleigh BOTDA system of NRZ and RZ is carried out.
【學(xué)位授予單位】：華北電力大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TP212

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 郝蘊(yùn)琦;葉青;潘政清;蔡海文;瞿榮輝;;Digital coherent detection research on Brillouin optical time domain reflectometry with simplex pulse codes[J];Chinese Physics B;2014年11期

2 饒?jiān)平?萇亮;賈新鴻;張超;;基于拉曼放大和半導(dǎo)體光放大的BOTDA[J];電子科技大學(xué)學(xué)報(bào);2012年04期

3 張超;饒?jiān)平?賈新鴻;鄧?yán)?萇亮;冉曾令;;光脈沖編碼對(duì)基于拉曼放大的布里淵光時(shí)域分析系統(tǒng)的影響[J];物理學(xué)報(bào);2011年10期

4 梁浩;路元?jiǎng)?李存磊;王祥傳;張旭蘋;;基于相關(guān)序列脈沖的布里淵光時(shí)域反射測(cè)量系統(tǒng)解碼方法研究[J];光學(xué)學(xué)報(bào);2011年10期

5 宋牟平;鮑，

本文編號(hào)：1861080