MH370 Data Communication Logs

《MH370 Data Communication Logs》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、NotesforSignallingUnitLogfor(9M-MRO)FlightMH370ThissetofnotesandaccompanyingtablesisintendedtoprovideareadablesummaryofthedatacommunicationlogsfromtheInmarsatsatellitesystemprovidedtotheauthoritiesinconnectionwiththeongoinginvestigationandsearchandrescuea

2、ctivitiesrelatingtoMH370.AlltimesareinUTCThetablebelowisareadableformofthelogfilerecordedatthegroundearthstationforthecommunicationswiththeterminalonMH370from16:00tothelastHandshakeRequest(LogOnInterrogation)attemptat01:16UTCSomecolumnswhichcontainnoma

3、terialinformationhavebeenremovedfromthetablesbelowforreadabilityAnexampleofacompletemessageforasinglelogentry:FieldHeadings:Time,AESID,DPAESOwner,ChannelName,OceanRegion,GESID(octal),ChannelBearer,ChannelUnitID,ChannelType,SuperframeNumber,FrameNumber,Slo

4、tNumber,SUNumber,SUType,SUTypeCode,SUContents,QNumber,ReferenceNumber,AckControl,SDMFigure,CRCCorrect,MissedT-ChannelBurst,Broadcast,RxPower(dBm),C/No,FrequencyOffset(Hz),EstimatedBER,BurstTimingOffset(microseconds)Examplemessage:7/03/201416:42:04.408,352

5、00217,SITADP(3047),IOR-R1200-0-36ED,IOR,305,RxPrimary,4,R-ChannelRX,12184,,5,,0x62-AcknowledgeUserData(R-channel),62,1FD06275008FC57A4E00000000000000007F89,D,0,E,S31,Yes,No,No,-57.29,40.09,146,0,14920UnderstandingtheBurstTimingOffset(BTO)values:Theroundt

6、riptimeforamessageisacombinationof:1.Timefromthegroundstation→satellite→aircraft→satelliteїŐƌŽƵŶĚƐƚĂƟŽŶ2.Processingtimewithinthegroundstation,satelliteandaircraftterminal,whichareconstantTheBTOisavalue(inmicroseconds)relativetoaterminalatanominalfixedl

7、ocation.OnlyR-Channelmessagesareused.TheBTOthereforeallowsthedeterminationofthedistancebetweenthesatelliteandtheaircraft.Itdoesnotprovidetheactualaircraftlocation1UnderstandingtheBurstFrequencyOffset(BFO)values:Thetransmissionsignalpathfromtheaircraftha

8、stwocomponentsaffectedbyDopplershift;betweenthesatelliteandaircraft,andbetweenthesatelliteandgroundstationThefollowingneedtobeconsideredwhencomputingtheexpectedfrequencyoffset:oInmarsatClassicAeromobileterminalsare