( .. GSM , , 4, 1999 .). ( 9600 /) ( 1120 ) , , .
GSM .
- 2000 () GPRS (General Packet Radio Service), , . GPRS . Nokia GSM, , GSM. GPRS , , IP-.
GPRS GSM , . GSM GPRS .1.
BTS (Base Transceiver Station) - ;
BSC (Base Station Controller) - ;
MSC (Mobile Switching Centre) - ;
SGSN (Serving GPRS Support Node) GPRS;
GGSN (Gateway GPRS Support Node) GPRS;
PCU (Packet Controller Unit) ;
OMC-G (Operating & Maintenance-GPRS) GPRS
.1. GPRS
, GSM (TDMA). TDMA , 8 (). : .
GSM GPRS . 1 7 , 8.
GPRS (CS-1... CS-4), , . , (.1.).
1.
, / | ||
CS-1 | 9,05 | 1/2 |
CS-2 | 13,4 | 2/3 |
CS-3 | 15,6 | 3/4 |
CS-4 | 21,4 |
, 8 ( ) GPRS 21,4 x 8 = 171,2 /. 100 /, , , GSM.
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EDGE ( Enhanced Data Rates for GSM). GMSK 8- 8PSK. 3- , .. . EDGE 384 /.
, . TETRA, , 28,8 /. , , .
. ( ..), ( , ..).
. GSM , . . , , GPRS , . (. .., .., .. , , 6, 1999 .). , , , , .
GSM , , . , , , .
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. , , GSM. , , Siemens, .
, , , , , . , , , . .
, , , , , , , . .