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- See Carrier-to-noise ratio.
- Satellite bandwidth or channel.
- Carrier; carrier frequency
- Continuous (usually high-frequency) electromagnetic wave which can be modulated
by a baseband signal to carry information; main frequency on which a voice, data
or video signal is sent.
- Carrier-to-noise ratio
- C/N: the ratio of the received carrier power and the noise power in a given
bandwidth, expressed in dB. Cascading Concatenating connection of devices.
- Frequencies in the 4-6 GHz range, used both for terrestrial microwave links
and satellite links.
- Recommendation developed by the CCIR for the digitization of colour video
signals; now ITU-R BT.601
- Code division multiple access: refers to a multiple-access scheme where the
transmission process uses spread-spectrum modulations and orthogonal codes to
avoid the signals interfering with one another.
- Centre frequency
- Frequency of the centre of a channel on a satellite transponder.
- Conference Europeane des Administrations des Postes et des Telecommunications.
- Coast earth station: alternative term for LES in INMARSAT system.
- Code of Federal Regulations (US).
- Transmission path; usually in an SNG uplink referring to the equipment that
makes up the transmission channel.
- Specific frequency range in which a signal is transmitted in a satellite transponder.
- Data bits added for error detection.
- Set of integrated circuit devices which form the heart of a compression encoder.
- Colour signal.
- Common intermediate format: developed so that computerized video images could
be shared from one computer to another. An image that is digitized to CIF format
has a resolution of 352 × 288 or 352 × 240, which is essentially one-half of CCIR-601.
- Circular polarization
- Geometric plane in which the electromagnetic signals are transmitted. Circular
polarization can be either clockwise (left-hand circular polarization, or LHCP)
or counter-clockwise (right-hand circular polarization, or RHCP).
- Video processing circuit that removes the energy dispersal signal component
from the video waveform.
- Clarke Belt; Clarke Orbit
- Geostationary orbit; named in honour of Arthur C. Clarke.
- Clean carrier
- Unmodulated carrier signal.
- Studio audio output transmitted to the remote site so that the reporter is
able to conduct a two-way dialogue with the studio presenter. Also called IFB,
mix-minus, return sound or return audio.
- Cliff-edge effect
- Describes the fact that digital signals suffer from achieving either perfect
results or nothing: as a digital signal passes a particular threshold, the signal
fails catastrophically with no warning.
- Coaxial cable, used for carrying signals at frequencies from video baseband
up to IF.
- COder/DECoder: a device which converts an analogue signal into or from a digital
- Coding delay
- See Latency.
- Coding order
- Order in which a group of pictures is coded in a digital compression process.
- Mathematical term for a number with a particular algebraic significance.
- Where a number of satellites share the same geostationary orbital assignment.
- Common carrier
- Regulated telecommunications company which will carry signals for a fee; common
carriers include telephone companies as well as owners of communications satellites.
- COMpressing/exPANDING: a noise-reduction technique that applies compression
at the transmitter and complementary expansion at the receiver.
- Process of removing redundant data to minimize the use of bandwidth, ideally
without visibly or audibly degrading the programme.
- Convolutional code
- Type of error correction code used in digital coding.
- Form of signal distortion in which modulation from one or more RF carrier(s)
is imposed on another carrier.
- Cross-polar discrimination
- XPD: measurement of immunity from interference from signals on the opposite
polarization; describes the ratio of (wanted) signals on the desired polarization
compared to the (unwanted) signals on the opposite polarization.
- Cross-polar interference
- XPI: interference from signals in the same transponder (IPs) or adjacent transponders,
and signals at similar frequencies but on the opposite polarization - related
- Process on-board a satellite where an uplinked signal in one frequency band
is converted to a different frequency band for the downlink, e.g. C-band uplink
to Ku-band downlink.
- Unwanted leakage of signal from one channel to another.