WI-FI
2009
621.391 (075.8)
32.884. 73
20 / .. , ..
WI-FI
. , 2009. 85 .
ISBN 978601709861-2
WI-FI, .
, 050719 ,
. 54, . 9, . 8 .
32.884. 73
..-.., . ..,
..., . ..
2009 .
ISBN 978601709861-2
ã , 2009 .
1 | |
1.1 | |
1.2 | |
2 IEEE 802.11 | |
2.1 IEEE 802.11 | |
2.2 802.11 | |
2.3 IEEE 802.11 | |
3 | |
3.1 | |
3.2 | |
3.3 | |
4. | |
4.1 | |
4.2 | |
5. | |
5.1 | |
5.2 | |
5.3 | |
5.4 / | |
5.5 | |
5.6 | |
5.7 | |
6. | |
6.1 | |
6.2 | |
7 | |
7.1 | |
7.2 | |
7.3 | |
7.4 | |
7.5 Wireless Distribution System | |
8 | |
WI-FI ( Wireless Fidelity, ) . 802.11 (IEEE). WI-FI IEEE , (PWAN, , , ) , (WWAN).
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, . Wi-Fi-. JiWire , , 56139 - 93 [1].
WI-FI (WLAN) . WI-FI 2,4 5 2 /. 200 . , , WI-FI (-) , , , - ( , , Wi-Fi) , , .
, IEEE 802.11, , . , .
. . . , , , . , , ; [2].
- , . , , c. , , . -, , . , .. - . , , .
. ( ), . , , : . ; , . . , .
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. ( ), , , , . , , / .
, , , t si. To , .
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(Frequency Division Multiplexing, FDM) , ( 1.1). , .
1.1 -
, . , .
, , , .
(Time Division Multiplexing, TDM). , . . s, ti ( , ) ( 1.2).
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1.2 -
, . , .
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, , - , . TDM-, GSM, .
(Code Division Multiplexing, CDM). , - , , . CDM (CDMA CDM Access) IS-95a, (cdma2000, WCDMA .). s t, ci.
, . . , . .
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CDM- , . , . () ( ) CDM- . CDM-. , , 1 0. . CDM- . , ( ) . CDM- () , CDM-, . , , (). , . (DSSS Direct Sequence Spread Spectrum), .
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: , , . , , . .
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OFDM . , , . OFDM , , , IEEE 802.11a/g.
OFDM . -, , . , . , OFDM . , ( ) . OFDM N , N . , Ts, OFDM NTs. . N , NTs .