NETGEAR HA501 - 802.11a Wireless 32-Bit Card Bus Adapter, Reference Manual

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7
Wireless Channel Selection
IEEE 802.11a utilizes 300 MHz of bandwidth in the 5 GHz Unlicensed National Information Infrastructure (U-NII)
band. Though the lower 200 MHz is physically contiguous, the FCC has divided the total 300 MHz into three distinct
domains, each with a different legal maximum power output.
U-NII Band Low Middle High
Frequency (GHz) 5.15 – 5.25 5.25 – 5.35 5.725 – 5.825
Max. Power Output 50 mW 250 mW 1W
Note: The high band is not supported in HA501 Wireless Adapter.
IEEE 802.11a uses Orthogonal Frequency Division Multiplexing (OFDM), a new encoding scheme that offers certain
benefits over a spread spectrum in channel availability and data rate. The 802.11a uses OFDM to define a total of 8
non-overlapping 200 MHz channels across the 2 lower bands; each of these is divided into 52 subcarriers and each
carrie
r is approximately 300 KHz wide. By comparison , 802.11b uses only 3 non-overlapping channels.
The HA501 user can use eight channels in non-turbo mode
.
Turbo mode: OFF
Channel
Frequency
36 5.18 GHz
40 5.20 GHz
44 5.22 GHz
48 5.24 GHz
52 5.26 GHz
56 5.28 GHz
60 5.30 GHz
64 5.32 GHz