Cisco GS7000 Installation And Operation Manual page 67

Q
QAM
quadrature amplitude modulation. A 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.
R
RCVR
receiver.
reverse path
Signal flow direction toward the headend.
RF
radio frequency. The frequency in the portion of the electromagnetic spectrum that is above
the audio frequencies and below the infrared frequencies, used in radio transmission systems.
RFI
radio frequency interference.
RMA
return material authorization. A form used to return products.
RPS
reverse path switch.
RX
receive or receiver.
S
S/N or SNR
signal-to-noise ratio. The ratio, in decibels, of the maximum peak-to-peak voltage of the video
signal, including synchronizing pulse, to the root-mean-square voltage of the noise. Provides
a measure and indication of signal quality.
SM
status monitor.
SM/LCM
status monitor/local control module.
4022871 Rev C
Glossary
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