Modern communication technology

Concept

Theso-calledcommunication,thesimplestandmostbasicunderstanding,isthemethodofcommunicationbetweenpeople.WhetheritisthetelephoneortheInternet,themostbasicproblemsolvedisactuallythecommunicationbetweenpeople.Moderncommunicationtechnologyishowtousethelatesttechnologytocontinuouslyoptimizevariousmethodsofcommunicationwiththecontinuousdevelopmentofscienceandtechnology,sothatcommunicationbetweenpeoplebecomesmoreconvenientandeffective.Thisisasystematicdiscipline,and3Gisanimportanttopicamongthem.

Overview

Communicationtechnologyandcommunicationindustryareoneofthefastestgrowingfieldssincethe1980s.Thisistruebothinternationallyanddomestically.Thisisoneoftheimportantsignsofhumanbeingsenteringtheinformationsociety.Communicationisintercommunicationofinformation.Inthissense,communicationhasexistedinancienttimes.Thedialoguebetweenpeopleiscommunication,andtheuseofgesturestoexpressemotionscanalsoberegardedascommunication.Inthefuture,theuseofbeacontoconveythesituationofwariscommunication.Ofcourse,thetransmissionoffilesbetweenKuaimaandthepostcanalsobecommunication.Moderncommunicationgenerallyreferstotelecommunications,whichiscalledtelecommunicationsintheworld.

Overviewofthedevelopmentofcommunicationisdividedintothefollowingthreestages:Thefirststageisthephaseoflanguageandtextcommunication.Atthisstage,thecommunicationmethodissimpleandthecontentissingle.Thesecondstageistheelectricalcommunicationstage.In1837,MorseinventedthetelegraphanddesignedtheMorsetelegraphcode.In1876,Bellinventedthetelephone.Inthisway,theuseofelectromagneticwavescannotonlytransmittext,butalsovoice,whichgreatlyacceleratesthedevelopmentprocessofcommunication.In1895,Marconiinventedradioequipment,thusopeningthewayforthedevelopmentofradiocommunication.Thethirdstageistheelectronicinformationcommunicationstage.Onthewhole,communicationtechnologyisactuallythetechnologyofcommunicationsystemsandcommunicationnetworks.Thecommunicationsystemreferstoallthefacilitiesrequiredforpoint-to-pointcommunication,andthecommunicationnetworkisallthefacilitiesthatcancommunicatewitheachotherbetweenmultiplepointscomposedofmanycommunicationsystems.Themainmoderncommunicationtechnologiesincludedigitalcommunicationtechnology,program-controlledswitchingtechnology,informationtransmissiontechnology,communicationnetworktechnology,datacommunicationanddatanetwork,ISDNandATMtechnology,broadbandIPtechnology,accessnetworkandaccesstechnology.

Digitalcommunicationiscommunicationthattransmitsdigitalsignals.Theanalogsignalsentbythesourceisencodedintoadigitalsignalthroughthedesireofthedigitalterminal.Thedigitalsignalsentbytheterminalbecomessuitableforchanneltransmissionthroughchannelencoding.Thedigitalsignalisthenmodulatedbythemodemtothedigitalchannelusedbythesystem,andthentransmittedtothepairofsegments,andfinallytransmittedtothesinkafterreversetransformation.Withitsstronganti-interferenceability,easystorage,processingandexchange,digitalcommunicationhasbecomethemostimportantcommunicationtechnologyfoundationinmoderncommunicationnetworks,andiswidelyusedinvariouscommunicationsystemsofmoderncommunicationnetworks.Program-controlledexchangetechnologymeansthatpeopleusespecialelectroniccomputerstostorepre-programmedprogramsinthecomputerasneededtocompletevariousexchangesincommunication.Program-controlledswitchingwasoriginallydevelopedfromtelephoneswitchingtechnology.Fromtheoriginalmanualswitchingoftelephoneswitching,automaticswitching,electronicswitching,andprogram-controlledswitchingtechnology,later,duetothecontinuousexpansionofthecommunicationbusinessscope,theswitchingtechnologyhasnotonlyItisonlyusedfortelephoneexchange,butalsocanrealizetheexchangeoffax,data,imagecommunicationandsoon.Program-controlleddigitalswitcheshavefastprocessingspeed,smallsize,largecapacity,strongflexibility,andmultipleservicefunctions,whichareeasytochangeswitchfunctions,facilitatetheconstructionofintelligentnetworks,andprovideuserswithmoreandmoreconvenienttelephoneservices.Astelecommunicationsservicesshiftfromvoice-basedtodata-based,switchingtechnologyhasalsograduallyshiftedfromtraditionalcircuitswitchingtechnologytopacket-baseddataswitchingandbroadbandswitching,aswellasadaptingtotheintegratedcharacteristicsofIP-basedservicesinthenextgenerationnetwork.Thedirectionofsoftswitchdevelopment.

Informationtransmissiontechnologymainlyincludesopticalfibercommunication,digitalmicrowavecommunication,satellitecommunication,mobilecommunicationandimagecommunication.

Opticalfiberisacommunicationmethodthatuseslightwavesasthecarrierfrequencyandopticalfiberasthetransmissionmedium.Itsmainfeatureisthefrequencybandwidth,whichis104~105timeshigherthanthecommonmicrowavefrequency;lowlossandrelaydistanceLong;withanti-electromagneticinterferenceability;thinthread,lightweight;andcorrosionresistance,notafraidofhightemperatureandotheradvantages.

Digitalmicrowaverelaycommunicationreferstoacommunicationmethodthatuseselectromagneticwaveswithawavelengthof1m~1mmtotransmitsignalsthrougharelaystation.Itsmaincharacteristicsarethatthesignalcanbe"regenerated";itisconvenienttoconnecttodigitalprogram-controlledexchanges;itisconvenienttoadoptlarge-scaleintegratedcircuits;ithasgoodconfidentiality;thedigitalmicrowavesystemoccupiestheadvantagesofawiderfrequencyband.Therefore,althoughdigitalmicrowavecommunicationhasonlybeenmorethan20yearsHowever,togetherwithopticalfibercommunicationandsatellitecommunication,ithasbeenrecognizedinternationallyasthethreemostpromisingtransmissionmethods.

Satellitecommunicationissimplythecommunicationcarriedoutbetweenradiocommunicationexhibitionsontheearthusinghumansasrelaystationsontheearth’ssatellites.Itsmaincharacteristicsare:thecommunicationdistanceislong,andtheinvestmentcosthasnothingtodowiththecommunicationdistance;theworkingfrequencybandwidth,largecommunicationcapacity,suitableforthetransmissionofmultipleservices;thecommunicationlineisstableandreliable;thecommunicationqualityishigh.

Theearlyformsofcommunicationbelongedtothecommunicationbetweenfixedpoints.Withthedevelopmentofhumansociety,informationtransmissionbecamemoreandmorefrequent.ItispreciselybecauseoftheadvantagesofflexibleinformationexchangeandobviouseconomicbenefitsthatmobilecommunicationhasachievedrapidThedevelopmentofmobilecommunication,theso-calledmobilecommunication,isthecommunicationrealizedduringthemovement.Itsbiggestadvantageisthatitcancommunicatewhilemoving,whichisconvenientandflexible.Mobilecommunicationsystemsmainlyincludedigitalmobilecommunicationsystem(GSM)andcodemultipleaccesscellularmobilecommunicationsystem(CDMA).

Forthecommunicationnetwork,itismainlydividedintothetelephonenetwork,thesupportnetworkandtheintelligentnetwork.Thetelephonenetworkisatelecommunicationsnetworkthatconductsinteractivevoicecommunicationsandopenstelephoneservices;acompletetelecommunicationsnetworknotonlyhasabusinessnetworkthatmainlytransmitsinformation,butalsoneedsseveraltoensurethenormaloperationofthebusinessnetworkandenhancenetworkfunctions.Thesupportnetworkthatimprovesthequalityofnetworkserviceisthesupportnetwork,andthesupportnetworkmainlyincludesNo.7Signalingnetwork,digitalsynchronizationnetworkandtelecommunicationmanagementnetwork.Theintelligentnetworkisanadditionalnetworkstructureestablishedonthebasisoftheoriginalnetworkforrapid,convenient,economical,andflexiblegenerationandrealizationofvariousnewtelecommunicationsservices.

Inthefieldofcommunication,informationcangenerallybedividedintothreetypes:voice,dataandimage.Dataisacombinationofdigitalsignalswithacertainmeaning,suchasletters,numbersandsymbols.Theseletters,numbersandsymbolsareexpressedonebyonebydiscretedigitalsignalsduringtransmission.Datacommunicationistosandwichsuchdatasignalsonthedatatransmissionchannel.Transmission,acommunicationmethodinwhichtheoriginaldatainformationiscorrectlyrestoredafterarrivingatthereceivinglocation.Itsmaincharacteristicsare:man-machineormachine-machinecommunication,thedirectparticipationofthecomputerincommunicationisanimportantfeatureofdatacommunication;hightransmissionaccuracyandreliabilityrequirements;hightransmissionrate;largedifferencesincommunicationduration.Thedatacommunicationnetworkisanetworkcomposedofdataterminalequipment,dataexchangeequipmentanddatatransmissionlinksdistributedinvariousplaces,whichcompletesdatatransmissionanddataexchangebetweendataterminalsunderthesupportofcommunicationprotocols.

Datanetworkistheproductofthecombinationofcomputertechnologyandthedevelopmentofmoderncommunicationtechnology.Itistheintegrationofinformationcollection,transmission,storageandprocessing,andisdevelopingtowardsamoreadvancedcomplex.Throughoutthedevelopmentofcommunicationtechnology,althoughthereisonlyashorthistoryofmorethanonehundredyears,earth-shakingchangeshavetakenplace,fromtheinitialmanualswitchingtothelatercircuitswitching,program-controlledswitching,packetswitching,andthefutureATMswitchesandIProutersforpacketizedcorenetworks;fromasinglefixedphonetosatellitephones,mobilephones,IPphones,etc.,aswellasvariousotherservicescombinedwithcommunicationsandcomputers,thethird-generationcommunicationstechnologywillbelaunchedsoon.Aswellasthefourthgenerationofcommunicationsinthefuture,withthedevelopmentofcommunicationstechnology,humansocietyhasgraduallyenteredaninformationsociety.

Abriefhistory

In1962,thefirsttransatlantictelevisionbroadcast:OnJuly11,1962,"Telestar1"wasintheUnitedStatesTestsoftransatlantictelevisionbroadcastingandtransmissionofmultipletelephonesweresuccessfullycarriedoutbetweenAndoverStationinMainPark,GunshiStationintheUnitedKingdomandPulemo-HakataStationinFrance.

OnJuly26,1963,theNationalAeronauticsandSpaceAdministrationoftheUnitedStateslaunchedthe"SyncomⅡ"(SyncomⅡ)communicationssatellitefortelephone,telegraph,andfaxcommunicationsbetweenAfrica,EuropeandtheUnitedStates.Sincethissatellitehasaninclinationof30degrees,itsorbitmovesinafigureofeightrelativetotheground,ratherthanbeingtruly"synchronized",soitcannotbecalleda"stationarysatellite."

SyncomSatellite

OnAugust23,1963,PresidentKennedyquotedMorse’sfirstpublictelegrammessage"WhatamiracleGodhascreated"andendedhisrelationshipwithTheNigerianPrimeMinister’sconversation.Thiswasthefirsttelephoneconversationviathe"Syncom"communicationssatellite,andthevoicetraveledmorethan72,000kilometers.

In1964,theworld’sfirstgeostationarystationOrbitalcommunicationsatellite:August19,1964,TheUnitedStateslaunchedthe"SyncomIII"satellite.Thisistheworld'sfirstgeosynchronousgeostationaryorbitcommunicationsatellite.OnDecember18,1958,theUnitedStateslauncheditsfirstcommunicationssatellite.Duetotechnicalreasons,itonlyworkedfor13days.Sincethen,satellitecommunicationhasenteredtheexperimentalstage.From1963to1964,theUnitedStateslaunchedthreeexperimentalgeostationarysatellites,andonlythethirdsatellite"Synchronous3"wascompletelysuccessful.

In1964,satellitecommunicationsbusinessbegan:OnAugust20,1964,the"InternationalCommunicationsSatelliteConsortium"headedbyUSCommunicationsSatelliteCo.,Ltd.wasestablished,andthenamewaschangedthefollowingyear"InternationalTelecommunicationsSatelliteOrganization",namelythefamousINTELSAT.TheorganizationisheadquarteredinWashington,anditspurposeistoproposeanddevelopaglobalcommunicationssatellitesystemthatcanbeusedbyallcountriesintheworldwithoutdiscriminationinordertoimproveitstelecommunicationsservices.Thesatellitecommunicationsystemandtheperformancestandardsofthestandardearthstationwereestablished,andthesatellitecommunicationservicehassinceofficiallybecomeaninternationalcommercialservice.

1965,SynchronousSatelliteThebeginningofthecommunicationera:OnApril6,1965,theInternationalSatelliteCommunicationsOrganization(INTERSAT)launchedasemi-experimentalandsemi-practicalgeostationarycommunicationsatellite-"EarlyBird"(EarlyBird),alsoknownas"Intelsat1",astheworld'sfirstpracticalsatelliteCommercialcommunicationssatellites,whichprovidecommunicationsservicesbetweenNorthAmericaandEurope,usheringinaneweraofsatellitecommercialcommunications."MorningBird"marksthetransitionofsatellitecommunicationsfromtheexperimentalstagetothepracticalstage,andthebeginningoftheeraofsynchronoussatellitecommunications

ThecommunicationssatelliteChenbird

Openedin1999GlobalMaritimeDistressandSafetySystem:OnFebruary1,1999,theGMDSSsystemwasfullylaunchedinshippingcountriesaroundtheworld.Unlikethepreviouslywidelyuseddistresssignal"SOS",GMDSSisanewship-to-shorecommunicationsystem-the"GlobalMaritimeDistressandSafetySystem".Itconsistsoftwomajorparts:asatellitecommunicationsystemandaterrestrialradiocommunicationsystem.Thesatellitesystemalsoincludestwoparts:theInternationalMaritimeSatelliteSub-systemandtheVeryLowOrbitSearchandRescueSatelliteSub-system.GDMSSisanadvancedsystembasedonadvancedsatellitecommunicationtechnology,digitaltechnologyandcomputertechnology.Whenashipisindistress,itcannotonlysendrescueinformationtoalargerarea,morequicklyandreliably,butalsoautomatically,Thesemi-automaticmethodreplacesthepreviousmanualalarmmethod.