Extreme Networks Altitude 300-2, Руководство по началу работы

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Altitude 300-2™ Getting Started Guide 15
Radio Characteristics
The Altitude 300-2
™
has two radios. The first supports the IEEE 802.11a
standard that uses a radio modulation technique known as Orthogonal
Frequency Division Multiplexing (OFDM). It operates in the 5 GHz region. Data
is transmitted over a half-duplex radio channel operating at up to 54 Megabits
per sec.
The second radio has two modulation modes both using half-duplex access. The
first modulation mode, Direct Sequence Spread Spectrum (DSSS), is used with
IEEE 802.11b clients. It operates up to 11 Mbps. The second modulation, OFDM,
is used with IEEE 802.11g clients. Like 802.11a it operates up to 54 Mbps. These
modulations use the 2.4 GHz band. In this band the Altitude 300-2
™
detects
what clients are present and selects the modulation mode.
Radios for both bands support antenna diversity. The Altitude 300-2i
™
has two
integrated antennas. These antennas are dual band, operating simultaneously in
the 2.4 GHz and 5 GHz bands. The Altitude 300-2d
™
has external antenna
connectors that support attachable antennas that operate in the 2.4 GHz and
5 GHz bands.
CAUTION
External antennas must be certified by Extreme Networks or selected by a
professional installer to ensure they meet all regulatory requirements.
NOTE
The Altitude 300-2d
TM
is designed for diversity with two antenna connectors for
each radio. It is import for the proper operation of the wireless port that
antennas be installed on each connector.