11G IS STILL COMPATIBLE WITH 11B, USING THE SAME MODULATION AN...
802.11g is still compatible with 802.11b, using the same modulation and coding as 802.11b
for the 1-, 2-, 5.5-, and 11-Mbps rates. To achieve the higher data rates, 802.11g uses or-
thogonal frequency division multiplexing (OFDM) for modulation. OFDM is the same
modulation that 802.11a uses.
There are still only three nonoverlapping channels. With OFDM, you must be careful
about power outputs; the power needs to be reduced to handle the peaks in the modula-
tion technique and still fall within governmental regulations. Table 6-4 shows some details
about 802.11g.