低軌衛(wèi)星通信網絡基于自主定位的位置區(qū)設計.pdf

1、電子科技大學碩士學位論文低軌衛(wèi)星通信網絡基于自主定位的位置區(qū)設計姓名：孫燦申請學位級別：碩士專業(yè)：通信與信息系統(tǒng)指導教師：朱立東20080501ABSTRACTAbstractLEOsatellitecommunicationSystemsareanimportantpartofthefutureglobalpersonalcommunicationinfrastructuresAnimportantaspectoftheLEOsate

2、llitenetworkistomanagethelocationofbothusersandsatellitesManynetworksignalflowsanddatabaseupdatesandqueriesarerequiredtOaccomplishsuchataskAstheGPSsystemisupgrading，andtheEuropeanGalileosystem，RussianGLONASSsystem，Chines

3、e“Beidou’systemwillbebuilt，thepositioningserviceformobileuserswillbemoreandmoreconvenient。SowecitnconsiderthemethodologyfordefininglocationareainLEOsatellitesystemsbasedonuser’sindependentpositioningabilityInchapter2，ame

4、thodologyfordefiningfixedlocationareainLEOsatellitesystemforuserswhichhaveindependentpositioningcapabilityisproposedBycomparinguser’supdatingcostandpagingcostweCallgetthebestsizeoflocationareaTheresultsprovethatthereisno

5、correlationbetweenthebestsizeoflocationareaanduser’saveragecalIarrivetimeWeneedtodecidetheprecisionofthebestsizeoflocationareaaccordingtopracticalsituationindefiningfixedlocationarea。Inchapter3，Asinthemethodologyfordefin

6、ingfixedlocationareabasedonindependentpositioninginLEOsatellitesystems，usersmaycrosstheborderoflocationareasfrequentlyandsendmanylocationupdate(LU)messagesAmethodologyfordefiningcrossareaisproposedInchapter4，amethodology

7、fordefiningfuzzylogicdynamiclocationareaisproposedUser’Slocationupdateradiusischangedbasedonthejudgmentofalaser’smovementmodeinaperiodoftimeUser’Slocationupdateandpagingcostofdifferentupdateradiusinnormalandfuzzylogicdyn