Cisco GS7000 Installation And Configuration Manual page 154

Glossary
Mbps
megabits per second. A unit of measure representing a rate of one million bits (megabits) per
second.
multipath, multipath transmission
The phenomenon which results from a signal traveling from point to point by more than one
path so that several copies of the signal arrive at the destination at different times or at
different angles.
N
Nm
Newton meter. A measure of torque defined by the application of one Newton of force on a
lever at a point on the lever that is one meter from the pivot point. (1 Nm = 0.737561 ft-lb)
O
OIB
optical interface board.
P
PCB
printed circuit board.
PROM
programmable read-only memory. A memory chip on which data can be written only once.
Once data has been written onto a PROM, it cannot be written to again.
PWB
printed wiring board.
Q
QAM
quadrature amplitude modulation. An amplitude and phase modulation technique for
representing digital information and transmitting that data with minimal bandwidth. Both
phase and amplitude of carrier waves are altered to represent the binary code. By
manipulating two factors, more discrete digital states are possible and therefore larger binary
schemes can be represented.
QPSK
quadrature phase-shift keying. A phase modulation technique for representing digital
information. QPSK produces four discrete states, each state representing two bits of
information.
R
RCM
reverse configuration module.
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