The major types of satellite dishes include motor-driven dishes, multi-satellites, VSAT, and ad hoc satellites. Other types include DTH, SMATV, CABD, automatic tracking satellite dishes, and big ugly dishes.
A motor-driven satellite dish is mounted on a pole which rotates around an axis to detect and receive various satellite signals in the sky. It is driven by a stepper motor, which can also be controlled to face any satellite position in the sky. It's standards, DiSEqC, USALs, and 36v posit
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Low Earth Orbit (LEO) refers to a satellite which orbits the earth at altitudes between (very roughly) 200 miles and 930 miles.
Low Earth Orbit satellites must travel very quickly to resist the pull of gravity -- approximately 17,000 miles per hour. Because of this, Lowe Earth Orbit satellies can orbit the planet in as little as 90 minutes.
Low Earth Orbit satellite systems require several dozen satellites to provide coverage of the entire planet.
Low Earth Orbit satellites typically op
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A transponder is an automatic electronic monitoring or control device that receives, cross-examines, amplifies and retransmits the arriving signal. It is primarily implemented in wireless communication. The word ‘Transponder’ itself is a combination of two words; transmitter and responder (occasionally abbreviated to TPDR, TR, XPNDR, and XPDR).
A transponder works by receiving a signal on a component called "interrogator" since it effectively inquires for information, then automatically t
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A retrograde orbit is an orbit where the satellite travels in an East to West direction instead of the common West to East orbit. The normal West to East orbits are known as prograde orbits.
Retrograde orbits are uncommon due to the much higher velocities necessary for successful launch and the associated higher costs. During a prograde launch, rotational velocity of the Earth is added to the velocity of the launch rocket. In a retrograde launch, the rotational velocity of the Earth is sub
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L band is a fequency range between 390MHz and 1.55GHz which is used for satellite communications and for terrestrial communications between satellite equipment.
The high frequencies utilized by C band, Ku band, and Ka band would suffer from high signal loss when transported over a copper coax cable such as an Intra-Facility Link.
An LNB is used to convert these higher frequency bands to L band, which can be transmitted over the IFL and processed by the IDU.
Some satellites transmit on L
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ODU (Out-Door Unit) refers to the set of satellite equipment which is placed outside of the building.
The ODU typically includes a satellite dish, a feedhorn, and a LNB (Low Noise Block). In bi-directional satellite systems, the ODU will also include a BUC (Block Up Convertor).
The ODU is connected to the IDU (In-Door-Unit) by the IFL (Inter-Facility-Link).
The dish receives the signal and focuses it on the feedhorn. The feedhorn delivers the signal to the LNB. The LNB converts the
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MCPC stands for Multiple Channel Per Carrier.
MCPC is a form of satellite transmission where each carrier is utilized to transmit multiple channels.
MCPC transmits multiple video or audio channels on one carrier by utilizing Time Division Multiplexing (TDM).
The alternative to MCPC is SCPC (Single Channel Per Carrier).
MCPC is used much more than SCPC because it makes much more efficient use of expensive satellite bandwidth.
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