Onthebasisofconsideringdownlinkpowerfluxdensitylimit,shadowingeffectfrequencyreuseindifferentsystemsandadjoiningbeamsofsamesystem,adoptingvoiceactivityandpolarizationisolationtechniques,thecapacityofCDMAmobilesatellitecommunicationsystematdifferentdownlinkpowerfluxdensitylimitmodes,channelspreadbandwidthandmobileuser’squalityfactorofreceivingsystem(G/T)areanalysedandcalculated,andcomparedwiththeonesofTDMAandFDMA.Theconclusionsaregivenattheendofthispaper.
