User Guide: Technical Reference APPENDIX B GLOSSARY OF TERMS
PRELIMINARY
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B-2
Azimuth
The horizontal angle in degrees between true North and the direction the antenna
is pointed.
B
Band
A portion of the Electromagnetic frequency spectrum.
Bandwidth
The range of frequencies over which a device will transmit information.
Baseband (BB)
Transmission
An analog term that applies to the small section of the transmit side of the
information stream between the STEL-2000 DSSS chip and the IF up conversion
mixer. There are only digital signals in the receive side. Both the DSSS transmit
and receive sides are “digital baseband” processed, although some analog
baseband functions are also performed.
Beamwidth
The beamwidth of a dish antenna is the angle of sky that can be illuminated
(picked up or sent out) by the dish. Large antennas have narrow beamwidths,
which reduces the noise from its sides. Smaller antennas have wider beamwidths
and, therefore, are noise.
Binary
A Base-2 numbering system. A binary code consists of elements represented by
two distinct conditions such as 0-1, on-off, or mark-space. This numbering system
is the basis for digital code.
Bipolar eight Zero
Substitution (B8ZS)
A line coding scheme to eliminate data streams with 8 or more consecutive zeros
by substituting 000+-0-+ for 00000000 if the preceding pulse was +, and 000-+0+-
for 00000000 if the preceding pulse was done to maintain density.
Bit
A single element in a binary code. An abbreviation for binary digit.
Bit Error Rate (BER)
A measure of the number of errors in a digital transmission. Typically given as an
exponential number that represents the ratio of errors to total bits.
Bit Error Rate Tester
(BERT)
A tester used for measuring the BER.
Bit Rate
The speed at which bits are transmitted by a system, typically expressed in bps.
BNC
A bayonet-locking connector for coaxial cable. Short for Bayonet-Neill-Concelman.
Byte
A data unit consisting of eight bits.
C
Carrier to Interference ratio
(C/I)
The ratio of the power of the carrier signal and an interfering signal.
Channel
A specific band of frequencies designated for a specific purpose; the data path
between two nodes.
