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CDMA 2000. Sustavi za vođenje i praćenje proces Franjo Pongrac. Što je CDMA?. Standard za 3G mreže koji uveo veće brzine prijenosa podataka ... Baziran na CdmaOne (2G) Code Division Multiple Acces. Otkuda CDMA?.
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CDMA 2000 Sustavi za vođenje i praćenje proces Franjo Pongrac
Što je CDMA? • Standard za 3G mreže koji uveo veće brzine prijenosa podataka ... • Baziran na CdmaOne (2G) • Code Division Multiple Acces
Otkuda CDMA? • 1999 godine ITU (International Telecommunication Union) je odobrila 5 radio pristupa (interface) za IMT -2000 standarde • Do kraja 2005 bilo je približno 170 comercijalnih CDMA i WCDMA sustava te oko 250 milijuna korisnika diljem svijeta
Kako radi CDMA? • Svakom korisniku dodijeljen jedinstveni kod • Svaki korisnik u prostoru šalje svoju informaciju sa jedinstvenim kodom • Svi korisnici odašilju istovremeno podatke u istom frekvencijskom području!!! • Kodovi odabrani tako da čine 128 vektorsku ortogonalnu bazu – SPREAD SPECTRUM
Sistem ćelija • 7 ćelija = 1 Cluster (ćelije upravljane BSCom) • Svi BSCovi čine PLMN i upravljani su sa MSCom • U čitavoj ćeliji isti frekvenciski pojas!!!! • Ostaje više prostora za bolju kvalitetu govora
Razvoj CDMA • CdmaOne (2G) • CDMA2000 1xRTT (1 times Radio Transmission Technology) 144kbps • CDMA2000 1xEV-DO(1x Evolution-Data Optimized, originalno 1x Evolution-Data Only) • CDMA2000 1xEV-DV (1x Evolution-Data/Voice) • CDMA 2000 3x
PSDN BSC BTS BSC HLR SMS-SC BSC PLMN MSC/VLR MSC/VLR BSC GMSC PSTN Tandem Tandem CO CO CO Tipična 2G Arhitektura BTS — Base Transceiver Station BSC — Base Station Controller MSC — Mobile Switching Center VLR — Visitor Location Register HLR — Home Location Register
BTS — Base Transceiver Station BSC — Base Station Controller MS — Mobile Station MSC — Mobile Switching Center HLR — Home Location Registry SMS-SC — Short Message Service — Serving Center STM — Synchronous Transfer Mode IS-95 BTS A Ref (A1, A2, A5) STM over T1/T3 MS BSC Proprietary Interface STM over T1/T3 or AAL1 over SONET Ater Ref (A3, A7) BTS IS-95 A Ref (A1, A2, A5) STM over T1/T3 BTS MS BSC Proprietary Interface A1 — Signaling interface for call control and mobility Management between MSC and BSC A5 — Full duplex bearer interface byte stream (SMS ?) A7 — Bearer interface for inter-BSC mobile handoff A2 — 64 kbps bearer interface for PCM voice A3 — Signaling interface for inter-BSC mobile handoff 2G cdmaOne (IS-95 + IS-41)
BTS — Base Transceiver Station BSC — Base Station Controller MS — Mobile Station MSC — Mobile Switching Center HLR — Home Location Registry SMS-SC — Short Message Service — Serving Center STM — Synchronous Transfer Mode IS-2000 STM over T1/T3 or AAL1 over SONET BTS A Ref (A1, A2, A5) STM over T1/T3 MS BSC Proprietary Interface AQuarter Ref (A10, A11) IP over Ethernet/AAL5 BTS RADIUS over UDP/IP PDSN — Packet Data Serving Node AAA — Authentication, Authorization, and Accounting A10 — Bearer interface between BSC (PCF) and PDSN for packet data Home Agent — Mobile IP Home Agent A11 — Signaling interface between BSC (PCF) and PDSN for packet data CDMA2000 1x Network
IS-2000 IS-2000 RADIUS over UDP/IP 1xEVDO — IP Data Only
SIP SCTP/IP SS7 IS-2000 H.248 (Maybe MGCP) SIP Circuit switched voice SIP Proxy — Session Initiation Protocol Proxy Server MGCF — Media Gateway Control Function SGW — Signaling Gateway (SS7) MGW — Media Gateway (Voice) IS-2000 Nextgen MSC ? 1XEVDV — IP Data and Voice Packet switched voice
Zašto CDMA? • Povećani kapaciteti govora • Veći i brži prijenos podataka • Multicast servisi • Fleksibilnost frekvencijskog spektra • Dulje trajanje baterije • Sinkronizacija • Kontroliranje potrošnje • Govorni i podatkovni kanali • Dodatni kanali • Potpuna kompatibilnost sa starijim sustavima • Podrška za servise za višestrukim platformama...
Za one koji žele znati više http://www.geocities.com/rahulscdmapage/ Technical/CDMAPrimer.pdf http://www.tiaonline.org/standards/technology/ cdma2000/cdma2000table.cfm