User Manual

AirLink Pro T1/E1 Rack Mount Installer’s Guide
Glossary
Rev. B - 1/97
D-5
hub configuration A system configuration in which several AirLink ProT1/E1
units are co-located. Usually, one unit acts as the burst
synchronization master for all the other units at the site.
jitter Jitter is short-term, high-frequency variations of the
significant instants (clock measuring points) from their ideal
position in time.
kbps The abbreviation/notation for “one thousand bits per second.”
kHz The abbreviation/notation for kilohertz, “one thousand
cycles per second.”
line-of-sight An unobstructed view from the transmit antenna to the
receive antenna.
LOS Loss of Signal. Declared upon detection of 175 ± 75 consecutive
zeros.
Mbps
Megabits per second; 1 million, or 10
6
digital bits per second.
MHz
Megahertz; 1 million, or 10
6
cycles per second.
OOF Out of Frame. An OOF condition is when errors are detected
in at least two out of four, or three out of five consecutive
framing bits.
Order Wire An auxiliary communications channel provided for use by
maintenance and service personnel. It allows voice
communications between the local and remote AirLink Pro
T1/E1 sites.
path loss The total amount of radio signal attenuation (loss) between
the transmitting antenna and the receiving antenna; the sum
of attenuation caused by obstacles located in the path and the
free space path loss.
power output The power of the radio signal as it leaves the RF unit.
pseudo-random noise Noise that satisfies one or more of the standard tests for
statistical randomness. Spread-spectrum modulated carrier
transmissions appear as pseudorandom noise to a receiver
that is not locked to, or is incapable of correlating a locally-
generated pseudorandom code with the received signal.
pseudo-random noise sequence
An operation in which a random stream of data bits is