Instruction manual
Page 65
Page 65 of 74 UTY4422-001
Appendix C
Glossary of Terms
AMBER
-
An LED with the red and green both “On.”
ASIC
- Application-specific Integrated Circuit:
BLINK
- An LED which is ON for 250 mS and OFF for 250 mS, with the pattern continuing for
some time, is said to “Blink.” See Table 14, Page 30. Also, see “Flash” and “Flutter.”
COMPEL
™ - Wegener's patented satellite network control system. This is a system which
features a control data stream embedded along with the payload services, where a single central
control site may control all aspects of network operation: database management, program
selection and setup by site, grouping of sites, scheduling, etc.
DAC
- Digital-to-Analog Converter. A device that converts a sequence of numbers
representing signal amplitudes in electronic binary format to actual analog signals.
EEPROM
- Electrically-Erasable Programmable Read-Only Memory. This acronym is used to
describe any non-volatile memory device which can be read- or written-to a nearly unlimited
number of times, but which retains its last written data when power is turned off.
FEC
- Concatenated FEC: Forward Error Correction. A method of mapping digital data for
transmission over a noisy, error-creating medium, and then un-mapping it, such that error-
reduction is achieved. This allows for lower-power (but wider bandwidth) carriers to be used
than would otherwise be required on a satellite link. Concatenated FEC means that a bit-level
convolutional FEC is embedded "inside" a byte or frame-level Reed-Solomon FEC within the
transmission path. This is done to create a far more powerful error-reduction system than either
type of FEC alone could provide.
FLASH
- An LED which is ON for 100 mS and OFF for 100 mS, with the pattern continuing for
some time, is said to “Flash.” See Table 14, Page 30. Also, see “Blink” and “Flutter.”
FLUTTER
- An LED which is ON for 50 mS and OFF for 50 mS, with the pattern continuing
for some time, is said to “Flutter.” See Table 14, Page 30. Also, see “Blink” and “Flash.”
MCPC
- Multiple-Channel-Per-Carrier. Means that one or more services or programs are
present on a particular radio-frequency carrier.
NVRAM
– Non-Volatile Random Access Memory – Random Access Memory which does not
‘lose’ its contents when power is off.
NTSC
- National Television Standards Committee. This is a shorthand description for the
standard 525-line, 30-frames-per-second analog baseband television signal format used in the
US.