Tiernan TE3000, Installation And Operation Manual

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Glossary 101
PSI
Program Specific Information.
PVC
Permanent Virtual Circuit—A logical dedicated circuit between two user ports in a
point-to-point configuration.
QPSK Quadrature Phase Shift Keying—The transmission of 2 bits per symbol, with each symbol
being a phase range of the sine wave. In this fashion, a 2 :1 compression ratio is achieved,
resulting in a doubling of the efficiency with which a circuit is employed.
RCD Remote Control Device— A computer terminal used to configure and monitor an encoder
or an IRD without using the unit’s control front panel.
RF input
The L-band, C-band, or KU-band input to an IRD.
sample rate
The number of times per second that an analog signal is measured and converted to a
binary number in order to convert the analog signal to a digital signal.
satellite downlink
frequency
Within a satellite system, the frequency, either C -band or Ku -band, of the signal
transmitted to the receiving dish.
SCPC
See single-channel-per-carrier
single-channel-per-
carrier
One video program transmitted per digital transport stream.
SNMP Simple Network Management Protocol—A widely used network monitoring and control
protocol. Data is passed from SNMP agents, which are hardware and/or software
processes reporting activity in each network device (hub, router, bridge, etc.) to the
workstation console used to oversee the network. The agents return information contained
in a Management Information Base, which is a data structure that defines what is
obtainable from the device and what can be controlled.
Sps
Samples per second— A ratio of the number of times that an analog signal is measured
and converted to a binary number to seconds elapsed, expressed as samples per second. 2.
Symbols per second —A ratio of symbols transmitted to seconds elapsed expressed as
symbols per second. Commonly used to express the speed at which QPSK symbols are
transmitted.
stereo pair
Two audio signals consisting of sound reproduction of the same audio source.
STM-1
Synchronous Transfer Mode—The SDH standard for transmission over OC-3 optical fiber
at 155.52 Mbps; refer to OC-3.
STS-3c Concatenated SONET Synchronous Transport Signal Level 3.
SVC Switched Virtual Circuit—A circuit between two user points in a point-to-point
configuration that is established by ATM signalling stack rather than being a dedicated
circuit.
symbol In digital transmission, a recognizable electrical state that is associated with a signal
element, which is an electrical signal within a defined period of time.
UL
Underwriters Laboratories.
VAC
Volts AC.
VDC
Volts DC.
VDE
Verband Deutscher Elektrotechniker—The German counterpart of the U.S. Underwriters
Laboratories.
Viterbi code rate Forward error- correction scheme.
Vpp Volts peak-to -peak.