11884.聲波測(cè)井?dāng)?shù)據(jù)壓縮算法的嵌入式開(kāi)發(fā)與實(shí)現(xiàn)

1、論文題目：聲波測(cè)井?dāng)?shù)據(jù)壓縮算法的嵌入式開(kāi)發(fā)與實(shí)現(xiàn)專業(yè)：通信與信息系統(tǒng)碩士生：曹芳彤（簽名）指導(dǎo)老師：蘇揚(yáng)（簽名）摘要測(cè)井是石油勘探和開(kāi)發(fā)過(guò)程中評(píng)估油藏的一種重要的方法，而聲波測(cè)井已成為當(dāng)前主流的一種測(cè)井技術(shù)。由于聲波測(cè)井會(huì)產(chǎn)生龐大的數(shù)據(jù)量，當(dāng)其要求的數(shù)據(jù)傳輸率過(guò)高而無(wú)法實(shí)時(shí)傳輸時(shí)，可采用存儲(chǔ)式儀器對(duì)這些數(shù)據(jù)進(jìn)行井下存儲(chǔ)。為了減小儀器的存儲(chǔ)壓力，需要對(duì)數(shù)據(jù)進(jìn)行壓縮處理。為此本文設(shè)計(jì)了一種基于LempelZivWelch（LZW）的聲波測(cè)井

2、數(shù)據(jù)壓縮算法，并進(jìn)行了嵌入式開(kāi)發(fā)與實(shí)現(xiàn)。首先，通過(guò)對(duì)常用的各種數(shù)據(jù)壓縮算法的優(yōu)缺點(diǎn)比較分析，并結(jié)合系統(tǒng)實(shí)際設(shè)計(jì)要求，選擇LZW算法作為核心算法，并針對(duì)LZW算法編碼時(shí)采用固定的碼長(zhǎng)進(jìn)行壓縮編碼的方式以及字典的存儲(chǔ)容量有限等方面的缺點(diǎn)，對(duì)LZW算法進(jìn)行了改進(jìn)。為了提高壓縮效率，本文提出了將MedianEdgeDetect（MED）模型與LZW融合的一種壓縮算法。通過(guò)MED模型對(duì)原始的聲波數(shù)據(jù)預(yù)測(cè)，并將其預(yù)測(cè)誤差作為數(shù)據(jù)壓縮的對(duì)象，再經(jīng)過(guò)改

3、進(jìn)的LZW算法壓縮，進(jìn)一步提高了壓縮效率。其次，根據(jù)嵌入式系統(tǒng)開(kāi)發(fā)的流程，在對(duì)系統(tǒng)需求分析的基礎(chǔ)上，確定了系統(tǒng)的硬件和操作系統(tǒng)構(gòu)成，選擇OK6410微處理器作為系統(tǒng)處理核心及Linux作為嵌入式開(kāi)發(fā)的操作系統(tǒng)，在此基礎(chǔ)上確定了系統(tǒng)硬件和軟件概要設(shè)計(jì)，隨后逐步說(shuō)明了數(shù)據(jù)壓縮、傳輸過(guò)程中需要解決的關(guān)鍵技術(shù)。最后將開(kāi)發(fā)板和PC機(jī)等設(shè)備相連后，對(duì)整個(gè)系統(tǒng)進(jìn)行了測(cè)試評(píng)價(jià)。實(shí)驗(yàn)測(cè)試結(jié)果表明，本文設(shè)計(jì)的聲波測(cè)井?dāng)?shù)據(jù)壓縮系統(tǒng)實(shí)現(xiàn)了聲波測(cè)井?dāng)?shù)據(jù)壓縮、數(shù)據(jù)

4、存儲(chǔ)、數(shù)據(jù)傳輸以及數(shù)據(jù)解壓恢復(fù)的功能。所提出的基于MED預(yù)測(cè)的LZW壓縮算法能夠大幅度提高壓縮效率，且能夠無(wú)失真地恢復(fù)數(shù)據(jù)，達(dá)到了預(yù)期的效果。這對(duì)聲波測(cè)井儀中聲波數(shù)據(jù)的壓縮與傳輸具有較高的應(yīng)用價(jià)值。關(guān)鍵詞：聲波測(cè)井；LempleZivWelch；MedianEdgeDetect；嵌入式系統(tǒng)研究類型：理論研究Subject：EmbeddedDevelopmentRealizationofAcousticLoggingDataCompres

5、sionAlgithmSpecialty：CommunicationInfmationSystemName：CaoFangtong(Signature)Instruct：SuYang(Signature)ABSTRACTLoggingisakindofimptantmethod，itcanevaluatereservoirintheprocessofoilexplationdevelopmentacousticloggingisacur

6、renttechnology.Theacousticloggingwillproducealargeamountofdatawhentherequireddatarateistoohightoachieverealtimetransmissionitcanusethedatastageinstrumenttostethedata.Inderteducethestagepressureinstrumentthedataneedtobeco

7、mpressed.TherefethispaperdesignedakindofacousticloggingdatacompressionalgithmwhichwasbasedonLempelZivWelch(LZW)completedembeddeddevelopmentimplementation..Firstofallthroughtheadvantagesdisadvantagesofvariousdatacompressi

8、onalgithmswerecomparedanalyzedaccdingtothedemoftheactualrequirementsofthesystemasthecealgithmLZWalgithmwased.LZWalgithmusedthefixedcodelengthcompressioncodingmethodlimitedstagecapacityofthedictionary.FthisshtcomingsLZWal

9、githmwasimproved.IndertoimprovethecompressionefficiencyinthispaperanewcompressionalgithmwasproposedwhichMedianEdgeDetect(MED)modelLZWwerecombined.MEDmodelpredictingtheiginalsoundwavesdatawasusedthepredictionerrwasusedast

10、heobjectofdatacompressionthentheimprovedLZWalgithmwasusedtocompressthedataitcanimprovethecompressionefficiency.Secondlyaccdingtotheprocessoftheembeddedsystemdevelopmentbasingontheanalysisofsystemrequirementsthecompositio

11、nofthehardwaresystemoperatingsystemweredeterminedOK6410microprocesswaschosenasthesystemprocessingceLinuxwaschosenasthedevelopmentofembeddedoperatingsystem.Onthisbasisthegeneraldesignofhardwaresoftwaresystemweredetermined

12、thentheintroducingofthekeytechnologyindatacompressiontheprocessofdatatransmissionneedtobesolved.Finallythedevelopmentboardcomputerwereconnectedtotestevaluatethewholesystem.Theexperimentaltestresultsshowthatthedesignedofa