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Defined by IEEE 802.11a.
Channel | 36 | centred on | 5180 MHz | (U-NII lower band, 5.15...5.25 GHz). |
" | 40 | " | 5200 MHz | " |
" | 44 | " | 5220 MHz | " |
" | 48 | " | 5240 MHz | " |
" | 52 | " | 5260 MHz | (U-NII middle band, 5.25...5.35 GHz). |
" | 56 | " | 5280 MHz | " |
" | 60 | " | 5300 MHz | " |
" | 64 | " | 5220 MHz | " |
" | 149 | " | 5745 MHz | (U-NII upper band, 5.725...5.825 GHz). |
" | 153 | " | 5765 MHz | " |
" | 157 | " | 5785 MHz | " |
" | 161 | " | 5805 MHz | " |
- The subcarriers are numbered −26 to +26. Subcarrier 0 (on the centre frequency of the channel) is not used.
- 4 subcarriers (−21, −7, +7, +21) are reserved as pilot carriers: they transmit a fixed bit sequence.
- 48 subcarriers carry useful data.
- The duration of each symbol is 3.2 µs (note: 1 / 3.2 µs = 0.3125 MHz, the subcarrier spacing).
- A guard period of 0.8 µs is added to each symbol, giving the total time between symbols of 4 µs.
Data rate (Mbit/sec) |
Modulation | Coding rate (R) |
Coded bits per subcarrier |
Coded bits per symbol |
Data bits per symbol |
6 | BPSK | 1/2 | 1 | 48 | 24 |
9 | 3/4 | 36 | |||
12 | QPSK | 1/2 | 2 | 96 | 48 |
18 | 3/4 | 72 | |||
24 | 1/2 | 4 | 192 | 96 | |
36 | 3/4 | 144 | |||
48 | |
2/3 | 6 | 288 | 192 |
54 | 3/4 | 216 |