Microwave Radio Communications SCM4000, Техническое справочное руководство

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Glossary A-1 SCM4000 Operator’s Guide/Tech Ref Manual
Glossary
This section describes acronyms and abbreviations used in
communications, broadcasting, and in our products and
documentation.
Table A-1: Useful Terms
Term Explanation
1RU 1 Rack Unit
16QAM 16-state Quadrature Amplitude Modulation
The signal (video + audio) is imposed onto the 70
MHz carrier by varying both the phase and the
amplitude of the signal while keeping the frequency
constant. There are 16 possible combinations of
phase and amplitude that can be used to carry
information.
32QAM 32-state Quadrature Amplitude Modulation
The signal (video + audio) is imposed onto the 70
MHz carrier by varying both the phase and the
amplitude of the signal while keeping the frequency
constant. There are 32 possible combinations of
phase and amplitude that can be used to carry
information.
4 FSK 4-state Frequency Shift Keying
8 PSK 8-Phase Shift Keying
8QAM 8-state Quadrature Amplitude Modulation
The signal (video + audio) is imposed onto the 70
MHz carrier by varying both the phase and the
amplitude of the signal while keeping the frequency
constant. There are 8 possible combinations of
phase and amplitude that can be used to carry
information.
64QAM 64-state Quadrature Amplitude Modulation
The signal (video+audio) is imposed onto the 70 MHz
carrier by varying both the phase and the amplitude
of the signal while keeping the frequency constant.
There are 64 possible combinations of phase and
amplitude that can be used to carry information.
A & C Alarm and Control
ACU AC to DC Converter Unit
ADPCM Adaptive Differential Pulse Code Modulation
AES Audio Engineering Society
AES/EBU Unofficial name for a digital audio standard
developed as a joint enterprise of the AES and the
EBU.
AFC Automatic Frequency Control
AGC Automatic Gain Control
AIS Alarm Indication Signal (all one’s)
AMI Alternate Mark Inversion, line code format for traffic
data.
AVG Average
Table A-1: Useful Terms (Continued)