NETGEAR HR314 - Wireless Router, Справочное руководство

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Reference Manual for the Model HR314 802.11a Hi-Speed Wireless Router
Network and Routing Basics B-13
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.
The radio frequency channels used are listed in Table B-4 :
Note: The high band is not supported in the Model HR314 802.11a Hi-Speed Wireless Router.
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 carrier is approximately 300
KHz wide. By comparison, 802.11b uses only 3 non-overlapping channels.
Table B-4. 802.11a Wireless Channels
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