قسمتی از اسلایدها پاورپوینت بررسی شبکه های سلولی موبایل -50 اسلاید در کل -23 اسلاید انگلیسی History of wireless communication n1897: Marconi demonstrated transmission of radio waves to a ship at sea 29 km away n1915: Wireless telephony established-- Virginia and Paris n1920's: Radio broadcasting became popular n1930's: TV broadcasting began n1946: First public mobile telephone service in US n1960's: Bell Labs developed cellular concept-- brought mobile telephony to masses n1960’s: Communications satellites launched nLate 1970's: IC technology advances enable affordable cellular telephony-- ushers in modern cellular era Modern cellular standards n1979: NTT (Japan), FDMA, FM, 25 kHz channels, 870-940 MHz n1983: AMPS (US), FDMA, FM, 30 kHz channels, 824-894 MHz n1985: TACS (Europe), FDMA, FM, 25 kHz channels, 900 MHz n1990: GSM (EuropeTDMA, GMSK, 200 kHz channels, 890-960 MHz n1991: USDC/IS-54 (), US), TD ...
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