.
- , . 50- ., . . 50 . 1971 ., 35 , 1980-1981 ., . . 25 . 25 : 700 , . , , !
, , , , . . , , , , , , 1971 . . , 1895 ., .
, . , . 1921 .: 2 , . - , - 2 ( -, 1933 .). 1934 . 4 30...40 , 1940 . 40 . , 1940 ., . 1940 . , 1946 . . , ; , 1947 . (Bell Laboratories), 1949 . .
.
, 1946 ., , () . , 150 , 1946 . (. -). 10 : 1955 . 11- 150 , 1956 . -12- 450 . : , . . , . ( ) 1964 1969 . , , . , , , .
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, , Bell System 1971 . . . 1985 . c , , . 15 , 1971 . 1985 ., , , , , . 1974 . 40 800 , 1986 . 10 , AMPS/DAMPS . 1978 . 2 . AMPS 1983 . - American Telephone and Telegraph (AT&T). , , , . . , NMT, . , . , : - 1908 ., - 1931 . , 160 , - 460 . 50- 60- . - . , 60- . . NMT.
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NMT - , 1953 . , , , - . 1969 . , . 1975 . , , 1978 . e 1981 . 1981 . NMT-450 ( 450 ) , 1981 . - , 1982 . - (), () (). , NMT-450 1981 . , Ericsson, NMT-450 .
NMT-450 NMT . 1983 NMT-900( 900 ), 1986 . NMT-450 NMT-900 , .
, , . NTT, AMPS, 900 . TACS, AMPS, 900 . TACS 1985 ., (ETACS, JTACS, NTACS) . , , .
. , () () , . : , .
, .
: (, , - ETACS) , , .
80- . - , .
900 1982 () - , 26 , - Group Special Mobile. GSM (, , GSM Global System for Mobile Communications). 1990 GSM, - . , , , , , - GMSK (Gaussian Minimum Shift Keying).
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He , - PCS (Personal Communication Services). 50%- 2000 . 1,9...2,0 ( PCS) 900 ( PCS).
1990 . TIA (Telecommunications Industry Association) IS-54 . D-AMPS ADC. , , , AMPS.
Qualcomm , ,-CDMA (Code Division Multiple Access).
1991 . DCS-1800 (Digital Cellular System 1800 ), GSM. , .
JDC (Japanese Digital Cellular), D-AMPS. 1992 . GSM. 1993 . TIA CDMA , IS-95. 1995 ., IS-95.
. -, NMT-450i ( NMT-450). 1994 . . NMT AMPS , GSM .
. CDMA.
. , XXI . , , , . . , UMTS ( ), - FPLMTS (Future Public Land Mobile Telephone System) - . FPLMTS . 1...3 , 60 170 - .
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3- - ( , , ) .
, - , ,
.
. , , , .
, . (GPS) . . , . - , ( ) , .
(ISO) (OSI). - . , .