802.11g 1, 2, 5,5, 6, 9, 11, 12, 18, 22, 24, 33, 36, 48 54 /. , . , . , 802.11g 802.11b/b+.
PBCC 5,5; 11; 22 33 /. 1; 2; 5,5; 6; 11; 12 24 /, (33, 36, 48 54 /) .
, 802.11g CCK OFDM, PBCC . . 3.
OFDM, 802.11g, .
, 802.11b (BDPSK), (QDPSK) . 802.11g ( ), BPSK QPSK. BPSK- , QPSK- . BPSK 6 9 /, QPSK 12 18 /.
QAM (Quadrature Amplitude Modulation), . 802.11g 16-QAM 64-QAM. 16 , 4 . 64 , 6 . 16-QAM 24 36 /, 64-QAM 48 54 /.
, : (. 2)? , , BPSK, 6 9 /. , OFDM , . . , BPSK- 1/2 6 /, 3/4 9 /.
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|
2. 802.11g | |||
, / | |||
() | DBPSK | ||
() | DQPSK | ||
5,5 | () | CCK | DQPSK |
() | PBCC | DBPSK | |
() | OFDM | BPSK | |
() | CCK-OFDM | BPSK | |
() | OFDM, CCK-OFDM | BPSK | |
() | CCK | DQPSK | |
() | PBCC | DQPSK | |
() | OFDM | QPSK | |
() | CCK-OFDM | QPSK | |
() | OFDM, CCK-OFDM | QPSK | |
() | PBCC | DQPSK | |
() | OFDM | 16-QAM | |
() | CCK-OFDM | ||
() | PBCC | ||
() | OFDM, CCK-OFDM | 16-QAM | |
() | OFDM, CCK-OFDM | 64-QAM | |
() | OFDM, CCK-OFDM | 64-QAM |
, , . , , / . CCK, , CCK. OFDM OFDM-. CCK-OFDM CCK-, OFDM-. , CCK-OFDM CCK OFDM. CCK-OFDM : PBCC CCK- PBCC.
3.
. 3. 1500 | ||||
, / | TCP, / | UDP, / | ||
802.11b | CCK | 5,9 | 7,1 | |
802.11g ( 802.11b) | OFDM/CCK | 14,4 | 19,5 | |
802.11g () | OFDM/CCK | 24,4 | 30,5 |