無線網(wǎng)絡(luò)視頻傳輸差錯(cuò)控制技術(shù)研究.pdf

1、Y952$21後旦大學(xué)碩士學(xué)位論文無線網(wǎng)絡(luò)視頻傳輸差錯(cuò)控制技術(shù)研究院專姓系：信息科學(xué)與【程學(xué)院業(yè)：通信與信息系統(tǒng)名：黎俊偉指導(dǎo)教師：完成門蔫H：高傳善教授2006年4月6復(fù)旦大學(xué)碩士學(xué)位論文AbstractW曲thefastdevelopmentofmultimedianetworktechniqueandmobilecommunication，theapplicationofvideocommunicationhasbecomemor

2、eandmorepopularInordertotransmitlessdatavideoneedscompression，whichremovestheredundantdataHowever’thecompressedvideodataishighlysensitivitytoerrorcodeinthetransmissionNomatterinthewirednetworkorinthewirelessnetworkerrorc

3、odeandlOSSofdataCan’tbeavoidedThewholenetworkstillcan’tprovideQualityofServiceguaranteeforthevideotransmissiontodayDuetothecongestion，packetsmaybelostorcorruptedinburstresultinginaseriousdegradationoftheimagequalitySoiti

4、snecessaryt0makeUSeoftheerrorcontroltechniquesHowever50meel慚controltechniquessuchasforwardIalTOrcorrectionandrepeatrequestarenotsuitableforthecaseofrealtimevideoapplicationSowemustworkcarefullytofindalleffectivewayInorde

5、rtohavemoreeffectiveerrorcontrolforthevideotransmissionoverwirelessnetworkwemeasuretheerrorlengthindifferentsituationsuchaswith／withoutbackgroundtrafficandunderaspecialratecontrolmethodAfteranalyzingthecommonarorcontrolt

6、echniques，weproposesomeerrorcontroltechniquesfortransmittingvideostreamingOVerwirelessnetworkFirstwedeployanadaptiveratecontrolmethodAfeedbackloopisaddedbetweentheserverandtheclientAfterreceivingthemessageaboutthenetwork

7、statetheservercarlautomaticallycontrolthesendingrateusingtheAIMDmethodThus，thevideotransmissionsystemcanavoidcongestionandmostofpacketlossSecond，weaddamacroblockreorderingprocessjntheencoderwhichmakestheconsecutivelostpa

8、cketsscatteredinthefimneThird，weaddanimprovederrorconcealmentalgorithminthedecoder111edecodercallchooseabeuermethodtoconcealtheerrorautomaticallybasedondifferenterrortypesandvideotypesWeapplyaboveerrorcontroltechniquesin