Glossary of Satellite, Telecommunications and Broadcasting Terms
'a la carte (service choice)
Choose whichever components of service you require.
addressed broadcast
Information sent to a single network user and/or group via a one-way broadcast system, also called "filecasting." A point-to-multipoint as opposed to point-to-point solution.
advertising
there are many methods of advertising on Thaicom Satellites, from inserted film to logos. For futher information contact sales representative sales@thaicom.net or call (662) 591-0736 to 49 Ext. 301
analog
Continuous variations in frequency/amplitude. The signals vary continuously instead of in discrete steps (digital). Most current audio/visual machines are analog. Spelt "analogue" in the UK.
antenna
A device for transmitting and/or receiving radio waves. Usually a parabolic- shaped dish.
aperture
A cross sectional area of the antenna which is exposed to the satellite signal.
asynchronous
A data transmission at irregular intervals (without reference to clock signals)
attenuation
Power loss of electromagnetic signals between transmission and reception points.
azimuth
The horizontal angle from true north (0 degrees) to a Thaicom satellite in a clockwise direction.
bandwidth
The difference between the highest and lowest frequencies of a channel measured in Hertz. Used to measure capacity.
baseband
baud
Data transmission speed.
bouquet
A package of television channels.
bits per second (bps)
A measure of data transmission speed.
carrier frequency
The main signal frequency - Thaicom transmitters operate in the band from 1 to 14 GHz.
C-band
Frequencies from 3.9 to 6.2 GHz.
Channel time shift packaging
allows viewers in different time zones to watch the same programs at different times.
coaxial cable
A type of cable used to transmit high frequency signals. Comprised of a central conductor surrounded by a shield wire.
codec
Short for coder/decoder, a device for coding or decoding signals.
compression
A technique used to increase the number of data bits per second sent over a data link or the available space on a storage device by replacing often-repeated characters, strings, and command sequences with a space-saving code.
DAMA (Demand-assigned Multiple Access
A method of allocating variable time slots to users on demand. Idle channels are kept in a pool; when capacity is requested an idle channel is allocated the requested bandwidth and assigned to the user.
DBS (Direct Broadcast Satellite)
Satellite transmission of (typically) television programming to small dish antennas at consumers’ homes.
declination offset
In a polar mount, the adjustment that compensates for the apparent angle of satellites 22,245 miles above the equator from the latitude of the antenna.
decoder
Equipment for decompressing a compressed data stream.
decryption
The recovery of the original data from an encrypted file or signal.
Demand Assigned Multiple Access (DAMA)
Coordination of VSAT links among earth stations in the Thaicom Network to access the transponder based on actual usage requirements and according to demand. Users need not have permanent links. DAMA technology helps share transponder resources and efficient use of frequency spectrum as well as reducing space segment cost and inventory for users (a form of pay as you use).
demodulation
The process of retrieving data from a modulated carrier wave; the opposite of modulation.
demultiplex
To separate a multiplexed data stream back into its original components.
digital
Data converted to numbers 0 and 1.
digital broadcasting
Converting TV pictures to numbers when transmitting and re-converting them to pictures when they are received.
digital compression
Squeezing digital information (like pictures or sound) into a smaller space to be able to transmit more quantity.
Digital Direct-to-Home (DTH)
Digital signals transmitted by Thaicom to a small satellite dish attached to a customer's television
downlink
A satellite to ground link.
Digital Video Broadcast (DVB)
A technical standard for digital broadcasting.
EIRP
Effective Isotropic Radiated Power
Edge of Coverage (EOC)
The outer geographical limit to which service can be provided.
earth station
Equipment for transmitting or receiving Thaicom satellite communications, such as a parabolic or dish antenna. Also called a ground station.
electronic setup
The prebroadcast time during which equipment is set up and tested.
electronic program guide
a text menu of programs showing to be shown on a channel.
elevation
The angle above the horizon (0 degrees) and directly overhead (90 degrees).
encode
To convert signals or data into a desired form.
encoder
A device capable of compressing a data stream.
encrypted subscriber management
A system that allows access to certain services to specific subscribers. Encryption means that the system is more secure than others.
encryption
The process of encoding, as in the scrambling of TV signals. Pay-TV transmission often is encrypted, and subscribers have devices that decrypt, or unscramble.
end of life (EOL)
The age at which a satellite may be expected to cease operations through lack of power or wear and tear. For Thaicom, this is about 15 years.
ENG
Electronic news gathering.
equalizer
A process that attempts to enhance the quality of a recording by filtering out distortions and other undesirable elements.
feed
The transmission of programming from a distribution center.
feedhorn
In satellite broadcasting, a part of a receiving antenna, usually a dish, that collects the signal reflected from the main surface reflector and channels it into a low-noise amplifier.
filecasting (file broadcasting)
Broadcasts of audio, video, and data files that are to be stored at the Thaicom Teleport for playback at a later time. Filecasting uses surplus carrier bandwidth and is therefore cost effective.
free-to-air
Television channels that do not charge the viewer. Money comes from advertisers.
frequency
The number of times that an alternating current goes through its complete cycle in one second of time. One cycle per second = one hertz.
frequency modulation (FM)
The encoding of a carrier wave by the modulation of its frequency. It produces little or no static and high fidelity reception. FM radio stations, from 88 to 108 megahertz produce reception superior to that of AM or amplitude modulation stations, particularly high-frequency sounds.
frequency-division multiplexing
Multiplexing is used with analog transmissions. Each signal modulates a carrier wave. Each carrier wave has a different frequency. The carriers are stacked on top of each other and transmitted simultaneously.
generation
In films and tapes, the master, or original, is called the first generation. Any copy made from the master is called second generation, or a copy, dupe, or dub, and a copy of a second-generation dupe is third generation.
gain
A measure of amplification, expressed in decibels.
Satellites circle the Earth in 24 hours, the same time it takes the Earth to rotate once. Once placed over the equator, they follow the Earth's rotation and appear continuously over a certain spot at 22,282 miles from the surface. They are high enough so that it takes only three satellites to cover the Earth's surface, except for the parts near the north and south poles.
gigahertz (GHz)
One billion cycles per second.
half-inch video
There are two types: VHS and Betamax are home use formats. They have very poor resolution. Betacam and MII are the two major broadcast-quality half-inch video formats. This term is commonly used to describe VHS dubs.
Hertz (Hz)
The number of cycles per second of a sound wave or electromagnetic wave.
high-definition television (HDTV)
A system with very high resolution. In HDTV, more lines per picture frame are transmitted than is standard, resulting in sharper, more vivid images.
Home shopping
TV broadcast of goods for purchase, sent directly to a viewer.
internet access
Thaicom Satellite are used for internet access for ISPs and consumers. To learn more visit our Internet via Satellite page
Integrated Services Digital Network (ISDN)
Digital, high-bandwidth lines that can deliver data over the Internet. Data travels at 128K bits per second.
Interactive ordering
Similar to home shopping but allows the shopper to order goods via an interactive method.
Interactive services
Services that allow the sender and receiver to exchange information simultaneously, as over the Internet.
interstitial programming
Putting short programs (2-25 mins) between full-length programs like movies.
International Telecommunications Union (ITU)
An internationally telecom standards body based in Geneva, Switzerland
None
kilocycle
1,000 cycles per second, called a kilohertz (kHz or khz). The number of kilocycles determines a station's frequency.
kbps kilobits per second
A measure of data transmission speed.
Ku band
The band of radio frequencies between 11 and 18 GHz.
leader
Non-magnetic strips of tape (either paper or plastic) at the beginning and end of film.
letterbox format
The ratio of width to height (the aspect ratio) needed to show widescreen movies at dimensions that fit a TV screen.
locked in
A videotape or other recorder that is moving at its regular speed and is ready to accept a feed.
locking up
The brief period when a videocassette wobbles as it starts to play before it stabilizes and runs smoothly.
Low Earth Orbit (LEO)
Satellites in low Earth orbit travel about 17,500 miles per hour, about a thousand kilometers above the Earth's surface. They can circle the Earth in about an hour and a half.
Medium Earth Orbit (MEO)
A medium altitude, in an approximately 10,000 12,000 km oval orbit, above either the north or south pole.
MHz (megahertz)
The frequency equal to one million Hertz, or cycles per second.
microwave
Line-of sight, point-to-point transmission of high-frequency radio signals (about 1 GHz and above).
minimicrowave
A video transmission from and outside-studio location to a mobile unit or a transmitter on a nearby roof. Thaicom satellite technology makes this method outdated.
mobile unit
A vehicle for outside broadcasts; also called a mobile production unit.
modulate
To change the frequency, phase, or amplitude of a carrier wave. A modulator is a device that modulates.
Moving Picture Experts Group (MPEG)
A standard for digital compression and decompression of audio and video file formats.
MTTF (Mean Time To Failure
The average time between hardware breakdown or loss of service.
multiplexing
A technique that merges several data streams into one in such a way that each can later be recovered intact.
None
None
package
A program or combination of programs or commercial spots offered to a sponsor as a unit, usually at a discount.
Packet IDentification field (PID)
The PID identifies all packets belonging to a particular program file. Each file has a unique PID.
PAL
Phase-alternation system. A TV and videotape standard.
parabolic antenna
The common shape of satellite antennas, described mathematically as a parabola. The parabolic shape focuses a weak microwave signal hitting the surface of the dish into a single focal point in front of the dish.
pay television (pay TV)
Home television programming for which the viewer pays by the program or by the month; also called pay-television, subscription television (STV), or toll-TV. Pay television includes over-the-air transmission (with encoded signals) and cable transmission (pay cable).
pay-per-view
Televised programs, such as cable television channels, that require payment by the viewer.
pay-per-view TV (PPV)
A system in which payment is made for a single showing of a program. Subscribers of the pay-television company can phone in their "orders" prior to a showing. Some companies supply an interactive piece of equipment to request programs without requiring a phone call.
preview channels
a channel that shows clips from programs to be shown at a later date.
permissioning
A method of permitting reception and decoding of data, audio, and/or video for network users.
picture-in-picture (PIP or P.I.P.)
A feature of television sets in which the viewer can see one videotape or program inside a small window on the screen while watching a videotape or another program on the same screen.
point-to-multipoint
A Thaicom satelite circuit connecting one place to many places.
point-to-point
A single Thaicom circuit connecting two locations.
polar mount
A type of satellite antenna mount with three basic adjustments, azimuth, polar axis, and declination offset. It tracks multiple satellites better than the AZ/EL type of mount.
polarization
In present C- and Ku-band systems, electromagnetic waves are polarized vertically or horizontally to reuse the same frequencies.
program package
A series of commercials to be broadcast on several programs of a station or network, offered in combination to an advertiser.
push technology
The means of automatically delivering information via the Internet to a pre-selected audience through audience members’ Web servers.
quad split
A TV switching effect to produce four different images on the screen at the same time.
Quadrature Phase Shift Keying (QPSK)
A four-phase digital modulation technique, used for modems and satellite communications. The technique modulates the phase of the carrier wave.
radio frequency (RF)
Frequencies from 100 kHz to 20 GHz.
rain outage
Loss of signal at Ku-band frequencies due to absorption and increased noise caused by heavy rainfall.
remote
A broadcast from a place other than the station's studio. Usually from a remote truck or van; also called remote pickup, pickup, field pickup, outside broadcast, or remo.
RF converter
A carrier wave mixing discrete audio and/or video signals into a composite RF modulated signal.
RF modulation
The way TV signals are transmitted.
running time
The time from the start to the end of a program.
satellite
A space relay station for audio and video transmission. Most communications satellites, like Thaicom, are in geostationary orbit (GEO).
satellite feed
A transmission from a satellite.
Satellite News Gathering (SNG)
Mobile satellite transmission equipment used for live broadcasts of outdoor events.
satellite news, or news-gathering, vehicle (SNF)
A van or other vehicle with equipment for transmission via satellite to TV station, usually including tape editing equipment.
signal re-transmission
The re-direction of a signal from a customer to a wider area than a local transmission can reach.
slot
Where a Thaicom satellite is positioned in orbit. Under ITU recommendations, 2 degrees is the minimum separation from another satellite.
Society of Motion Picture and Television Engineers (SMPTE)
An association in the USA of engineers and technicians in film, television, and related fields. SMPTE standards include the SMPTE time code, an 8-digit number that specifies on a videotape, the hour, minute, second, and frame number.
solar outage
Interference occurring when the sun passes behind or near a satellite and within the field of view of the antenna. Solar outages can be exactly predicted.
spotcasting
Broadcasts of special commercial spots to IRDs in a network.
station-keeping
Maintaining the orbit of a satellite at its optimum position.
strip
To demodulate a multiplexed signal.
subcarrier
A second signal "piggybacked" onto a main carrier.
submaster
A copy of an original tape, usually made as a backup in case the master is damaged or lost, also called a safety.
subscription television (STV)
Pay television, in which subscribers, or viewers, pay a monthly fee.
subtitle
A superimposed caption at the bottom of a TV screen.
synchronous
A data transfer at a fixed rate. The transmitter and receiver are controlled by clock pulses.
T1
A high-speed Internet connection, allowing transfer rates of 1.5 Mbps (megabytes per second).
T3
Faster than T1, a T-3 transfers information at a rate of 45 megabytes per second.
tape play-back
A Thaicom customer, usually a broadcaster, supplies a television program on a video cassette. This is broadcast to viewers from Thaicom's teleport.
teleport
A teleport (telecommunications port) is a hub that provides access to high-bandwidth services. The Thaicom Teleport and DTH Center is a gateway for satellite transmissions, allowing broadcasters, cablecasters, and public and private network operators to outsource non-core functions. Our Teleport feeds video, data and voice to Thaicom satellites, delivering time-sensitive television and radio programming to audiences globally. It also provides remote and underdeveloped regions with high-quality Internet and network connections.
terrestrial feed
Transmission via land lines or direct (without lines). Different from a satellite feed.
time code
A digitally encoded signal that is recorded on videotape as hours : minutes : seconds : frames.
time signal
A beep, sometimes accompanied by a commercial announcement; also called a time check.
time slot
A period in a transmission schedule. A program starting and ending at specific times is given a time slot, such as 7 p.m. to 9 p.m.
time-coding
The date and time recorded on the edge of a videotape as it is being shot, to assist in editing and record keeping.
tracking
Targeting a signal source, such as a satellite, by a tracking station and following that satellite.
Also, the adjustment in a VCR of the videotape playback position against the video reel heads.
trailer
A promotional announcement at the end of one program about a forthcoming program or a commercial attached to the end of a program or another commercial. Also, a short, blank strip at the end of a reel of tape.
transmission
The actual sending or beaming of the audio/video portion of the program from point to point.
transponder
In a Thaicom satellite, a device that receives a earth-based signal, shifts the signal’s frequency, amplifies the signal, and retransmits the signal to receivers on the earth.
turnaround
Receiving a signal from one satellite and re-broadcasting it to another. Thaicom satellites do this to send programs around the world.
tying in
A procedure for a local station to pick up or to join a network program after it has started.
ultra high frequency (UHF)
Limited-range wave bands for television channels
(14 to 82) that transmit from 470 to 890 megahertz (MHz), with lower power and over a smaller area than low-band (channels 2 to 6) or high-band (7 to 13) very high frequency (VHF) stations.
uplinking
Transmitting a signal up to a Thaicom satellite.
very high frequency (VHF or V)
Frequencies from 54 to 216 MHz.
Very Small Aperture Terminal (VSAT)
video
The visual portion of a broadcast or film; a synonym for television; short for videotape.
Video Home System (VHS)
A type of 1/2 inch video format different from Beta format. VHS-C, or VHS-Compact is smaller for camcorders. Super VHS (S-VHS) provides a sharper picture.
videotape
Magnetic tape for recording sound and picture. Requires a videotape machine such as a videocassette recorder (VCR) for showing on a TV set. The most common width of the tape is 1/2 inch. A videocassette is a videotape recording contained in a cassette; a videodisc is a recording on a record or disc for playback on videodisc players in homes.
