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- Contribution circuit: traditionally a terrestrial communications path linking
an earth station to a local switching network; now also refers to satellite contribution
- Process of reducing the input and output power levels of a travelling wave
tube to obtain more linear operation and hence minimize the risk of distortion.
Expressed in dB.
- Bandpass filter
- Active or passive circuit which allows signals within the desired frequency
band to pass but prevents signals outside this pass band from getting through.
- Measure of spectrum (frequency) use or capacity; the amount of information
that can be passed at a given time over a certain span of frequency.
- Basic rate ISDN
- ISDN service of 2 × 64 kbps bearers and a 16 kbps data control channel. Also
referred to as 2B+D.
- Rate of data transmission based on the number of symbols transmitted per second;
- Low-power carrier transmitted by a satellite which supplies the satellite
operations control centre on the ground with a means of monitoring telemetry data
and tracking the satellite.
- Signal from uplink or satellite.
- Angle or conical shape of the beam the antenna projects.
- Generic term for a carrier signal.
- Bit error rate: a measurement of the quality of a data link.
- See Digital.
- Colloquial term for satellite.
- Single digital unit of information.
- Bit error rate
- See BER: the fraction of a sequence of message bits that are in error. A bit
error rate of 10-6 means that there is an average of one error per million bits.
- Speed of a digital transmission, measured in bits per second.
- Continuous stream of data bits transmitted over a communication channel with
no separators between the character group.
- Land-line, cellular or satellite phone used for satellite co-ordination at
the SNG uplink.
- Block downconverter
- Device used to convert the C- or Ku-band signal down to L-band.
- A group of pixels in a compression process.
- Method of combining a number (n) of discrete data channels of data bandwidth
d to provide the user with a single combined data channel of n×d. Boresight Main
focus of an antenna; the direction of maximum gain of an antenna. Box Area in
which the satellite has to be maintained while in station-kept geostationary orbit;
see Station-kept box.
- Bits per second.
- Binary phase shift key: modulation technique.
- Basic rate ISDN; Basic Rate Interface (for ISDN).
- Referring to a bandwidth greater than the baseband signal; a single path that
has multiple independent carriers multiplexed onto it; a large bandwidth digital
- See Widebeam.
- Broadcast-Satellite Service: ITU service designation.
- Digital memory store on the input and output of a compression device.