ComStream CM601, Инструкция по установке и эксплуатации

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Glossary
BER
Bit Error Rate – the number of received bits that are in error relative to a specific
amount of bits received; usually expressed as a number referenced to a power of
10 (for example, 1.00E-05).
BERT
Bit Error Rate Tester – reports BER, errors, number of bits, blocks, and block
error rates with programmable data patterns.
bin Area of frequency searched during acquisition.
bps Bits per second
BPSK Bi-Phase Shift Keying - In BPSK modulation, zeroes and ones are represented by
two phases of the RF carrier signal which differ by 180 degrees. Such a signal
may be produced by mixing an RF carrier with a clocked data stream in a double-
balanced mixer.
dB
Decibel
DCE
Data Communications Equipment
demod
Demodulator
doppler buffer
Used to smooth out the periodic frequency variation in the received data rate
caused by satellite motion.
doppler shift Condition resulting from the slight drifting of satellites which occurs; the effect is
a slight difference in data rate clocks at the receive and transmit sites.
DTE
Data Terminal Equipment – any piece of equipment at which a communications
path begins or ends.
E
b
/N
0
Energy-per-bit with respect to noise, also known as signal-to-noise level; when
displayed on the CM701/CM601A front panel LCD or a remote terminal, E
b
/N
0
appears as Eb/No.
FEC Forward Error Correction
FIFO First-In First-Out
hot-swap Process of installing or swapping option cards into the CM701/CM601A while the
modem is not turned off and the power is not removed; NOT recommended for
CM701/CM601A cards unless HOT PLUG/PULL appears on the filler board.
IF Intermediate Frequency – the frequency to which a carrier is converted locally as
an intermediate step in transmission or reception.
I/O
Input/Output – refers to user equipment interface.
kbps
Thousand bits per second
kHz
Kilohertz