Glossary
114
Version 1.0 Rev B - 08/00
as the -3 dB points. A high gain antenna has a very narrow beamwidth and may be more
difficult to align.
BER
Bit Error Rate. A percentage of bits per million, showing the number of bits in error
compared to the data bits actually sent.
blocking
Blocking is an operating mode where the radio receives only. Unblocked is the normal
operating mode.
C
cable loss
The signal loss experienced as it passes through the coax cable. Expressed in dB.
channel
The width of the spectrum band taken by a radio signal, usually measured in
kilohertz (kHz).
coaxial cable
A type of wire where the inner conductor is surrounded by an outer conductor. The outer
conductor serves as an electrical shield.
collision
The situation that exists when two users try to send a signal over the same medium at the
same time, and the signal uses the same frequencies.
configuration menus
The menu based user interface on the Hopper Plus 120-24 that allows the viewing and
configuration of Hopper Plus 120-24 parameters.
contentionless polling
The Hopper Plus 120-24 uses a form of dynamic polling that ignores idle remote stations.
The number of polls that an idle remote is ignored can be set to maximize polling to active
stations.
Cross-Polarization Discrimination
See
XPD
.
D
dB
Decibel. A relative measure of power used to specify power gains and losses. The
difference in power P1 and P2 expressed in dB is:
DB9
A D-shaped connector with 9 pins.
dB
10
P
1
P
2
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