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User Guide and Technical Manual
Term
Defi nition
BISS-E
Basic Inter-operable Scrambling System-Encrypted
BISS-E is an variation of the scrambling system where the decoder has stored
one secure BISS-key entered by for example, the rights-holder. This key is
unknown to the decoder’s user. The user is sent a 16-digit hexadecimal code
which is entered as a session key. This session key is then mathematically
combined internally to calculate a BISS-1 key that can decrypt the signal.
BNC
Bayonet lock coaxial connector [Compare to TNC]
Bonding
The combination of several cellular network channels together creating single,
virtual high-speed connection.
BUC
Block Up-converter
A block up-converter [BUC] is used in the transmission [uplink] of satellite
signals. It converts a band of frequencies from a lower frequency to a higher
frequency. Modern BUCs convert from the L band to Ku band, C band and Ka
band. Older BUCs convert from a 70 MHz intermediate frequency [IF] to Ku
band or C band.
CDMA Modem
Code Division Multiple Access Modem
A CDMA Modem uses a digital radio system that transmits streams of bits [PN
codes]. CDMA permits several radios to share the same frequencies. Unlike
TDMA [Time Division Multiple Access], a system used in 2G GSM, all radios
can be active all the time, because network capacity does not directly limit
the number of active radios. CDMA cellular communication standard is most
commonly used in North America.
COFDM
Coded Orthogonal Frequency-Division Multiplexing
COFDM is a method of encoding digital data on multiple carrier frequencies.
COFDM is a frequency-division multiplexing [FDM] scheme used as a digital
multi-carrier modulation method. It is deemed coded because of the use of
forward error correction [FEC]. A large number of closely spaced orthogonal
sub-carrier signals are used to carry data on several parallel data streams
or channels. Each sub-carrier is modulated with a conventional modulation
scheme, such as quadrature amplitude modulation or phase-shift keying, at a
low symbol rate, maintaining total data rates similar to conventional single-carrier
modulation schemes in the same bandwidth.
COFDM-based transmitters with diversity receivers use DVB-T, which was
originally designed for high power stationary UHF transmitters fed highly
compressed video by rack mount encoders and stationary domestic receivers.
Composite [Baseband]
A band or grouping of frequencies and/or subcarriers, including video, occupied
by the signal in a radio transmission system. Also called Baseband.
