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智能pcf壓力傳感器系統(tǒng)的畢業(yè)論文-預(yù)覽頁(yè)

 

【正文】 圖52 逐次逼進(jìn)式, 新轉(zhuǎn)換技術(shù)圖53為逐次逼近式,新轉(zhuǎn)換器原理結(jié)構(gòu)圖。加碼由環(huán)形計(jì)數(shù)器完成,去碼? 留碼邏輯根據(jù)比較器輸出作去碼或留碼操作。去碼/留碼邏輯 環(huán)形計(jì)算器數(shù)據(jù)寄存器逐次逼近邏輯寄存器SAR電壓比較器模擬輸入A D/A轉(zhuǎn)換器至輸出數(shù)據(jù)鎖存器時(shí)鐘V1VfVR圖53逐次逼近式A/D轉(zhuǎn)換器原理圖 積分式A/D轉(zhuǎn)換技術(shù)經(jīng)典的雙重積分式A/D轉(zhuǎn)換器由積分器、比較器、計(jì)數(shù)器、模擬開(kāi)關(guān)和控制器組成(圖54)。在電路上保證兩個(gè)時(shí)間區(qū)間的積分值相等, 即:由此, 可得出的關(guān)系式為:。但值不能取得過(guò)大, 值越大, 要求A點(diǎn)(見(jiàn)圖54(b))的電壓擺幅越大, 積分電路輸出線性越差, 反而降低了A/D轉(zhuǎn)換精度。這樣, 前一個(gè)分周期結(jié)束之后, 在積分電容器上剩余的電荷將會(huì)對(duì)下一個(gè)分周期的結(jié)果產(chǎn)生影響, 只有在整個(gè)轉(zhuǎn)換結(jié)束時(shí)A/D轉(zhuǎn)換進(jìn)行清零, 剩余電荷才會(huì)丟失。值越大, 其轉(zhuǎn)換分辨率和精度越高, 但其A/D轉(zhuǎn)換速度卻降低了。 模數(shù)轉(zhuǎn)換器的電路結(jié)構(gòu)是由非常簡(jiǎn)單的模擬電路和十分復(fù)雜的數(shù)字信號(hào)處理電路構(gòu)成。1位DAC由串行輸出數(shù)據(jù)流驅(qū)動(dòng), 其輸出以負(fù)反饋形式與輸入信號(hào)求和, 積分器對(duì)兩信號(hào)的差值進(jìn)行積分, 如此往復(fù)循環(huán), 即可完成各調(diào)制, 積分器的輸出就是上述差值的累計(jì)值。 在使用模數(shù)轉(zhuǎn)換器設(shè)計(jì)電路時(shí), 除了對(duì)所有的轉(zhuǎn)換器都適當(dāng)接地、電容旁路去禍等通用規(guī)則外, 還應(yīng)注意: ①應(yīng)使轉(zhuǎn)換器驅(qū)動(dòng)電路盡量靠近轉(zhuǎn)換器以便把外部電路之間以及開(kāi)關(guān)電容節(jié)點(diǎn)之間引線產(chǎn)生的感抗減到最小, 從而減小輸入的建立時(shí)間并把從輸入端到線路板其它部件的輻射減到最??; ②必須考慮時(shí)鐘信號(hào)產(chǎn)生的干擾對(duì)ADC的影響; ③要考慮抗混疊問(wèn)題。本文分析了智能PCF壓力傳感器中的各個(gè)部分的工作原理。通過(guò)這次畢業(yè)論文,讓我再一次的回顧了大學(xué)四年來(lái)所學(xué)的知識(shí),驀然的發(fā)現(xiàn),我們所學(xué)的并不少,而是太多,從模擬電子技術(shù)、數(shù)字電子技術(shù)到信號(hào)與系統(tǒng),再到電磁場(chǎng)理論、光纖傳感技術(shù)等等,并且真正能用這些知識(shí)做出與之相關(guān)的項(xiàng)目來(lái),雖然我知道以我們現(xiàn)在情況,要做出一些技術(shù)方面的突破,幾乎是不可能的,但是讓我感覺(jué)到了所學(xué)意義的存在。在大學(xué)四年里,您治學(xué)嚴(yán)謹(jǐn),學(xué)識(shí)淵博,思想深邃,視野雄闊,為我營(yíng)造了一種良好的精神氛圍。參考文獻(xiàn)[1] J,. C, progress in photonic crystal fibers[J]. Proc OFC, 2000, (3): 98100[2] Knight J C, Birks T A, Russell P St J et al .AllS ilica S ingleMode Optical Fiber with Photonic Cryst al Cladding[ J] . Optics Letters,1996, 21( 19) : 1547—1549.[3] Broen g J, Mogilevst ev D, Barkou S E et al. Phot onic Cryst al Fibers: A New Class of Opt ical Waveguides [ J ] . Optical F iber T echnolog y, 1999, 5( 3) : 305—330.[4] L i Y, Wang C, Wang Z et al. Analyt ical Solut ion of the Fundament al Space Filling Mode of Phot onic Cryst al Fibers[ J] . Op tics and L aser Technol ogy , 2007, 39( 2) : 322—326.[5] 梁蘭菊,田貴才,張?jiān)J?,[J],光譜實(shí)驗(yàn)室,2010,27(2):551552.[6] 余先倫,羅映祥,鄭旭武,[J],光網(wǎng)絡(luò),2011,6:1113.[7] WOJTEK J B, CHEN Jiahua, TINKP Eftimov ,et al. A Photonic Crystal Fiber Sensor for Pressure Measurements [J].IEEE Trans. Instrum. Meas.,2006,55( 4) :11191123.[8] WOJTEK J B,URBANCZYK of sensitivity of birefringent holey fiber to temperature,elongation,and hydrostatic pressure,IMTC2004:12281232.[9] 余先倫,陳猛,[J],光通信研究,2011,4:5153.[10] Delg ado pinar M, Diez A, Cr uz J L , et al. H ig h Extinctio nRatio Polarizing Endlessly SingleMode Photonic Crystal Fiber [ J ] . IEEE Pho ton Techno l Lett,2007, 19( 8) : 562 564.[11] Li Jie, Mao Yuan, Lu Chao, et al. Po lar izing pr operties of phot onic cry sta l fiber s with high index cladding drfects [ J] . J Lig htw Techno l, 2010, 28 ( 11) : 16081614.[12] 蘇紅新,王坤,崔建華,[J],儀表技術(shù)與傳感器,2008,2:68.[13] 余先倫,[J],光器件,2008,11:3335.[14] 戴蓉,王春麟,傳感器世界[J],2000:2628.[15] 陸志梁編著,模數(shù)和數(shù)模轉(zhuǎn)換器(M),電子工業(yè)出版社,1988.[16] 孫圣和,王廷云,徐影編著,光纖測(cè)量傳感技術(shù)(M),哈爾濱工業(yè)大學(xué)出版社,2000.[17] 閻石,數(shù)字電子技術(shù)基礎(chǔ)(M),高等教育出版社,2006.The System Design of Intelligent Photonic Crystal Fiber Pressure SensorQIU Yinping(Physics and Electronic Engineering Dept. Chongqing Three Gorges University, Wanzhou 404000)Abstract:Pressure sensor is mon in industrial practice field,and it usually used in Industrial automatic control the rapidly development of photonic crystal fiber these year, intelligent PCF pressure sensor has widely used in every kinds of pressure in environmental paper explain basic principles and system position of intelligent PCF pressure sensor. Morever,apply the plane wave expansion method numerically simulate transmission characteristics of photonic crystal fiber,and explain PCF sensor’s decoding last, analyse some kinds of A/D conversion method,and put forward the best in PCFsensor.Keywords:Intelligent PCF Pressure Sensor, Photonic crystal fiber,PCF sensor decoding system,A/D conversion
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