Wilan LIBRA 5800 AP, Руководство пользователя

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Glossary
134 Libra 5800 Series User Guide
ASCII
American Standard Code for Information Interchange. A system used by personal computers to
convert letters, numbers and symbols into binary notation.
Automatic Frequency Control
A method by which the CPEs stayed tuned to the correct frequency for communicating with the AP,
despite frequency variations caused by the hardware.
attenuation
Any loss in signal strength, due to resistance, absorption, capacitance, or any characteristic of the
medium or design of the system.
B
Bandwidth
The size of a communications channel, measured in cycles per second. "Bandwidth" is often used as
a synonym for data rate.
base station
The central control unit of the wireless network. A base station polls remote units and routes traffic to
them. The base usually connects to a major access point of main network.
beamwidth
The beamwidth of an antenna describes how a signal spreads out from the antenna, as well as the
range of the reception area. Beamwidth is measured between the points on the beam pattern at
which the power density is half of the maximum power. These are often called the -3 dB points. A
high-gain antenna has a narrow beamwidth and may be more difficult to align.
BER
Bit Error Rate. The proportion of bits received with errors. The default measurement is per million
sent.
C
cable loss
The loss a signal experiences as it passes through a cable. Expressed in dB.
CAM
Content Addressable Memory.
channel
The width of the spectrum band taken by a radio signal, usually measured in kilohertz (kHz).
chip rate
Chip rate signifies the time occupied by a single frequency. Also the period of a code clock, or the
output of a code generator during one clock interval.