Earth Orbit Satellites
Satellite tv for pc must be correctly positioned within the corresponding orbit after leaving it within the area. It revolves in a selected method and serves its goal for scientific, navy or business. The orbits, that are assigned to satellites with respect to earth are referred to as as Earth Orbits. The satellites current in these orbits are referred to as as Earth Orbit Satellites.
We must always select an orbit correctly for a satellite tv for pc primarily based on the requirement. For instance, if the satellite tv for pc is positioned in decrease orbit, then it takes much less time to journey across the earth and there can be higher decision in an onboard digital camera. Equally, if the satellite tv for pc is positioned in increased orbit, then it takes extra time to journey across the earth and it covers extra earth’s floor at one time.
Following are the three vital kinds of Earth Orbit satellites −
- Geosynchronous Earth Orbit Satellites
- Medium Earth Orbit Satellites
- Low Earth Orbit Satellites
Now, allow us to talk about about every sort of earth orbit satellites one after the other.
Geosynchronous Earth OrbitSatellites
A Geo-synchronous Earth Orbit (GEO) Satellite tv for pc is one, which is positioned at an altitude of 22,300 miles above the Earth. This orbit is synchronized with a aspect actual day (i.e., 23 hours 56 minutes). This orbit can have inclination and eccentricity.
It might not be round. This orbit might be tilted on the poles of the earth. However, it seems stationary when noticed from the Earth. These satellites are used for satellite tv for pc Tv.
The identical geo-synchronous orbit, whether it is round and within the aircraft of equator, then it’s referred to as as Geostationary orbit. These Satellites are positioned at 35,900kms (similar as Geosynchronous) above the Earth’s Equator they usually carry on rotating with respect to earth’s course (west to east).
The satellites current in these orbits have the angular velocity similar as that of earth. Therefore, these satellites are thought of as stationary with respect to earth since, these are in synchronous with the Earth’s rotation.
The benefit of Geostationary orbit is that no want to trace the antennas with a view to discover the place of satellites.
Geostationary Earth Orbit Satellites are used for climate forecasting, satellite tv for pc TV, satellite tv for pc radio and different kinds of international communications.
The next determine reveals the distinction between Geo-synchronous and Geo-stationary orbits. The axis of rotation signifies the motion of Earth.
Notice − Each Geostationary orbit is a Geo-synchronous orbit. However, the converse needn’t be true.
Medium Earth Orbit Satellites
Medium Earth Orbit (MEO) satellites will orbit at distances of about 8000 miles from earth’s floor. Indicators transmitted from a MEO satellite tv for pc journey a shorter distance. As a result of this, the sign energy on the receiving finish will get improved. This reveals that smaller and light-weight weight receiving terminals can be utilized on the receiving finish.
Transmission delay might be outlined because the time it takes for a sign to journey as much as a satellite tv for pc and again all the way down to a receiving station. On this case, there’s much less transmission delay. As a result of, the sign travels for a shorter distance to and from the MEO satellite tv for pc.
For real-time communications, the shorter the transmission delay, the higher would be the communication system. For instance, if a GEO satellite tv for pc requires 0.25 seconds for a spherical journey, then MEO satellite tv for pc requires lower than 0.1 seconds to finish the identical journey. MEOs function within the frequency vary of two GHz and above.
These satellites are used for Excessive pace phone indicators. Ten or extra MEO satellites are required with a view to cowl complete earth.
Low Earth Orbit Satellites
Low Earth Orbit LEO) satellites are primarily categorized into three classes. These are little LEOs, massive LEOs, and Mega-LEOs. LEOs will orbit at a distance of 500 to 1000 miles above the earth’s floor. These satellites are used for satellite tv for pc telephones and GPS.
This comparatively brief distance reduces transmission delay to solely 0.05 seconds. This additional reduces the necessity for delicate and hulking receiving tools. Twenty or extra LEO satellites are required to cowl complete earth.
Little LEOs will function within the 800 MHz (0.eight GHz) vary. Huge LEOs will function within the 2 GHz or above vary, and Mega-LEOs operates within the 20-30 GHz vary.
The upper frequencies related to Mega-LEOs interprets into extra data carrying capability and yields to the potential of real-time, low delay video transmission scheme.
The next determine depicts the paths of LEO, MEO and GEO
Right here, a query might come up that with greater than 200 satellites which might be in geosynchronous orbit, how can we hold them from working into one another or from trying to make use of the identical location in area?
To reply this downside (query), worldwide regulatory our bodies just like the Worldwide Telecommunications Union (ITU) and nationwide authorities organizations just like the Federal Communications Fee (FCC) designate the areas on the geosynchronous orbit, the place the communications satellites might be positioned.
These areas are laid out in levels of longitude and are referred to as as orbital slots. The FCC and ITU have progressively diminished the required spacing all the way down to solely 2 levels for C-band and Ku-band satellites because of the big demand for orbital slots.