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2001-07-19 09:08Yesky.com
Ŀǰƶֻܻƶն˵ʵ֣ʹԽԽûϰƶͨŵķʽͬʱҲܹءκƵؽͨźͽ뵽ֻͨСӪ̡̺ṩ̶dzعȺƳģGSMCDMA뼼GPRSԼ3GͨŽ뼼ЩԤʾƶʱļЩȫϤһϤողѧʹֻôļҲһ㲻ϤˡﻹǰֻĽ뼼һ˵һ£ϣܸϤûٹһΣòϤû˽գ
1ģ
ģźģⷽʽеƣģ⼶õƵֶַģҹڽֻͨڸطֱ衢ʱȺͬаźĦֻͨϵͳԭģƶ绰γABϵͳAʹAֻBʹBֻBĵҪڱϺӱա㽭ĴɽȵأAĵDZϺԼӱɽȫиʡɼڴֵǹģԭDzܻͨġ19961ҹʡģƶ绰ϵͳʵģƶ绰пȫ30ʡʵԶΡҪABҪûԼֻϽвֻתΪBʹãBصAҲֻϲֻزʹãABʵֻͨ
ģźʧСʿ绰ڽ磬ƣȫؼоиǡģȱŵԽ٣Բ
2GSM
ʵGSMGlobal System for Mobile CommunicationsдΪȫƶͨϵͳҪķϵͳ֮һGSMõխTDMAһƵ(ѡ)ͬʱ8ͨǸŷޱȷƵʷΧ9001800MHz֮ƶ绰ϵͳƵΪ1800MHzϵͳҲɡGSM1991꿪ʼͶʹõġ1997ףѾ100ӪΪŷʵϵı
GSMҲнǿıԺͿԣͨȶ߱ƵԴʸߣӿڿţǿŵ㡣
3CDMA
CDMAGSMһҲƶͨϵͳһ֣ӢȫCode Division Multiple AccessֶַǸIS-95ƵƵ9001800MHzΧƶ绰ϵͳCDMAչƵ(Spread Spectrum)νչƵǽҪݵϢһضźźһԭźŻĿϴ俪ؽܵźźٽضźɾԭԭźšĺô밲ȫԺáʹTimeDivision Multiplexing (TDM)ľ(GSM)ͬCDMAÿһͨ߷һȷƵʣÿһƵʹṩȫƵס
CDMA¼ƣЧƵʺ滯ͨǿԡ߸ԡӳûͨʱ䡢͡лCDMAֻӽߵ绰źŸǺãCDMAϵͳñ뼼УУÿֻı뻹ʱ仯ʹֻܳΪϵĿܣһCDMAֻֻĿġ
4GPRS
GPRSȫΪͨݰϵͳ(General Packet Radio System)һݰΪ(Packet-Base)ͨѶϵͳGPRSƶû֮ṩһӣƶûṩIPX.25ݽGPRS÷齻öûijЩ̶ŵԴѿнӿϵTDMA֡е8ʱ϶ݣô߿ɴ164kb8.GSMнӿڵŵԴȿԱռãҲԱGPRSҵռáȻŵ£һЩŵΪGPRSרŵCDPDһ͵߹ϵͳ߾ͬǣͨĹ800Ƶ֮䣬ƵξһĴŽ١ܴﵽŵΪ19.2KbpsȥݴԼŵõһЩû˵ݴһΪ5-10Kbps߿Դﵽ15KbpsҡʹCDPDɵͨϵͳȫ˫ͨŷʽͬʱշݣͨͨFECǰԶط֤ϴݲֲ
GPRSڣݴٶȲWAPܱġĿǰGSMƶͨĴٶΪÿ9.6KֽڣGPRSֻڽƳʱѴﵽ56KbpsĴٶȣڸǴﵽ115Kbps(ٶdz56Kmodemʵ)ٶϵƣGPRS"Զ"ص㣬ûʱ籣ϵ
5PHS
PHSӢȫΪPersonal Handyphone SystemĺΪֻϵͳ,ϵͳձ籨˾ģ봫ͷʽȽߵȡPHSýϵ͵Ĺʷߵ粨źţʺǷΧСʺϳԵأҲϵ͡PHSṩͨŷݴܹ֧߶ýͨţΣPHSҲṩӿڣ磺ߵȡ绰·˵µȣƷdz㣬ֵܹ֧KTVֵͳվȣûճбͨŷĴٶΪ32KBPSƵϲķʽISDNݣ罫ƵͿԽISDNBƵ64KBPSĴ䡣
63G
3GӢȫΪThird Generation TechnologyĺΪƶͨżüֳΪƶ绰2000ü涨ƶնԳƶʱ䴫תΪ144kbps⾲ֹʱΪ384kbpsΪ2MbpsЩҪζûʾͿԴﵽ2MbpsΪʻڽϸƵʹ滮Լ֯ӪЭĽ̶ܳȡȻLANһĸҵѿɴ54Mbps3Gȫ̿ʱǺԤ2MbpsҵгΡرӦõ384kbpsʣһIPЭķҵȫΧڵõ㷺Ӧãǽ칫չκεط
3Gûר磨̫LANȣΡҪһЩƶIPȻüɼͨ磨PANʵƶ豸֮ӡ
ĵַ:http://www.cnonline.org/2001/article/1334.html
1ģ
ģźģⷽʽеƣģ⼶õƵֶַģҹڽֻͨڸطֱ衢ʱȺͬаźĦֻͨϵͳԭģƶ绰γABϵͳAʹAֻBʹBֻBĵҪڱϺӱա㽭ĴɽȵأAĵDZϺԼӱɽȫиʡɼڴֵǹģԭDzܻͨġ19961ҹʡģƶ绰ϵͳʵģƶ绰пȫ30ʡʵԶΡҪABҪûԼֻϽвֻתΪBʹãBصAҲֻϲֻزʹãABʵֻͨ
ģźʧСʿ绰ڽ磬ƣȫؼоиǡģȱŵԽ٣Բ
2GSM
ʵGSMGlobal System for Mobile CommunicationsдΪȫƶͨϵͳҪķϵͳ֮һGSMõխTDMAһƵ(ѡ)ͬʱ8ͨǸŷޱȷƵʷΧ9001800MHz֮ƶ绰ϵͳƵΪ1800MHzϵͳҲɡGSM1991꿪ʼͶʹõġ1997ףѾ100ӪΪŷʵϵı
GSMҲнǿıԺͿԣͨȶ߱ƵԴʸߣӿڿţǿŵ㡣
3CDMA
CDMAGSMһҲƶͨϵͳһ֣ӢȫCode Division Multiple AccessֶַǸIS-95ƵƵ9001800MHzΧƶ绰ϵͳCDMAչƵ(Spread Spectrum)νչƵǽҪݵϢһضźźһԭźŻĿϴ俪ؽܵźźٽضźɾԭԭźšĺô밲ȫԺáʹTimeDivision Multiplexing (TDM)ľ(GSM)ͬCDMAÿһͨ߷һȷƵʣÿһƵʹṩȫƵס
CDMA¼ƣЧƵʺ滯ͨǿԡ߸ԡӳûͨʱ䡢͡лCDMAֻӽߵ绰źŸǺãCDMAϵͳñ뼼УУÿֻı뻹ʱ仯ʹֻܳΪϵĿܣһCDMAֻֻĿġ
4GPRS
GPRSȫΪͨݰϵͳ(General Packet Radio System)һݰΪ(Packet-Base)ͨѶϵͳGPRSƶû֮ṩһӣƶûṩIPX.25ݽGPRS÷齻öûijЩ̶ŵԴѿнӿϵTDMA֡е8ʱ϶ݣô߿ɴ164kb8.GSMнӿڵŵԴȿԱռãҲԱGPRSҵռáȻŵ£һЩŵΪGPRSרŵCDPDһ͵߹ϵͳ߾ͬǣͨĹ800Ƶ֮䣬ƵξһĴŽ١ܴﵽŵΪ19.2KbpsȥݴԼŵõһЩû˵ݴһΪ5-10Kbps߿Դﵽ15KbpsҡʹCDPDɵͨϵͳȫ˫ͨŷʽͬʱշݣͨͨFECǰԶط֤ϴݲֲ
GPRSڣݴٶȲWAPܱġĿǰGSMƶͨĴٶΪÿ9.6KֽڣGPRSֻڽƳʱѴﵽ56KbpsĴٶȣڸǴﵽ115Kbps(ٶdz56Kmodemʵ)ٶϵƣGPRS"Զ"ص㣬ûʱ籣ϵ
5PHS
PHSӢȫΪPersonal Handyphone SystemĺΪֻϵͳ,ϵͳձ籨˾ģ봫ͷʽȽߵȡPHSýϵ͵Ĺʷߵ粨źţʺǷΧСʺϳԵأҲϵ͡PHSṩͨŷݴܹ֧߶ýͨţΣPHSҲṩӿڣ磺ߵȡ绰·˵µȣƷdz㣬ֵܹ֧KTVֵͳվȣûճбͨŷĴٶΪ32KBPSƵϲķʽISDNݣ罫ƵͿԽISDNBƵ64KBPSĴ䡣
63G
3GӢȫΪThird Generation TechnologyĺΪƶͨżüֳΪƶ绰2000ü涨ƶնԳƶʱ䴫תΪ144kbps⾲ֹʱΪ384kbpsΪ2MbpsЩҪζûʾͿԴﵽ2MbpsΪʻڽϸƵʹ滮Լ֯ӪЭĽ̶ܳȡȻLANһĸҵѿɴ54Mbps3Gȫ̿ʱǺԤ2MbpsҵгΡرӦõ384kbpsʣһIPЭķҵȫΧڵõ㷺Ӧãǽ칫չκεط
3Gûר磨̫LANȣΡҪһЩƶIPȻüɼͨ磨PANʵƶ豸֮ӡ
ĵַ:http://www.cnonline.org/2001/article/1334.html