Siemens IEEE802.11 - Manual (Page 19)

WLAN-IEEE802.11 Tutorial (Maximilian Riegel), 021018-wlan-tutorial.ppt Page 19 © Siemens, 2002
IEEE802.11
2.4 GHz & 5 GHz Physical Layers
Time
Fr
equenc
y
n
2.4 GHz Frequency Hopping Spread Spectrum
– 2/4 FSK with 1/2 Mbps
– 79 non overlapping frequencies
of 1 MHz width (US)
Frequency
Pow
e
r
Frequency
Pow
e
r
spreading
n
2.4 GHz Direct Sequence Spread Spectrum
– DBPSK/DQPSK with 1/2 Mbps
– Spreading with 11 Bit barker Code
– 11/13 channels in the 2.4 GHz band
n
2.4 GHz High Rate DSSS Ext. (802.11b)
– CCK/DQPSK with 5.5/11 Mbps
Frequency
Pow
e
r
n
5 GHz OFDM PHY (802.11a)
– Basic parameters identical to
HiperLAN2 PHY
– European regulatory issues
n
Baseband IR, 1 and 2Mbps, 16-PPM and 4-PPM