satellite ppt

PRESENTATION ON SATELLITE:

PRESENTATION ON SATELLITE Presented by: Amit Agrawal Rollno-0833713004 B.Tech (I.T.)

What is a Satellite?:

What is a Satellite? The word satellite originated from the Latin word “ Satellit ”- meaning an attendant, one who is constantly moving around the earth . For our own purposes however a satellite is simply any body that moves around another one in a mathematically predictable path called an orbit. A communication satellite is a staion in space that is used for telecommuncation , radio and television signals. There are about 750 satellite in the space, most of them are used for communication.

How do satellite work?:

How do satellite work?

How Do Satellite Work?:

How Do Satellite Work? Two Stations on Earth want to communicate through radio broadcast but are too far away to use conventional means. The two stations can use a satellite as a relay station for their communication. One Earth Station transmits the signals to the satellite. Up link frequency is the frequency at which Ground Station is communicating with Satellite. The satellite Transponder converts the signal and sends it down to the second earth station. This frequency is called a Downlink .

Consider The Light Bulb Example::

Consider The Light Bulb Example:

Satellite Orbits::

Satellite Orbits: Classification of orbits:

Classification of orbits::

Classification of orbits: Satellite orbits are also classified based on their heights above the earth: GEO LEO MEO

Satellite orbit Altitudes::

Satellite orbit Altitudes:

Geostationary Earth Orbit (GEO)::

Geostationary Earth Orbit (GEO): These satellites are in orbit 35,786 km above the earth’s surface along the equator. Objects in Geostationary orbit revolve around the earth at the same speed as the earth rotates. This means GEO satellites remain in the same position relative to the surface of earth. Advantages of GEO:- A GEO satellite’s distance from earth gives it a large coverage area, almost a fourth of the earth’s surface. These factors make it ideal for satellite broadcast and other multipoint applications

GEO contd.:

GEO contd. Disadvantages of GEO:- A GEO satellite’s distance also cause it to have both a comparatively weak signal and a time delay in the signal, which is bad for point to point communication. Launching of satellites to orbit are complex and expensive.

Low Earth Orbit (LEO):

Low Earth Orbit (LEO) LEO:- LEO satellites are much closer to the earth than GEO satellites, ranging from 0 to 5000 km above the surface. LEO satellites don’t stay in fixed position relative to the surface, and are only visible for 15 to 20 minutes each pass. A network of LEO satellites is necessary for LEO satellites to be useful Iridium system h as 66 satellites in six LEO orbits,each at an altitude of 750km

LEO Contd.:

LEO Contd. Advantages:- A LEO satellite’s disatance from earth compared to a GEO satellite gives it a better signal strength and less of a time delay, which makes it better for point to point communication. A LEO satellite’s smaller area of coverage is less of a waste of bandwidth. Disadvantages:- A network of LEO satellites is needed, which can be costly

Medium Earth Orbit (MEO):

Medium Earth Orbit (MEO) A MEO satellite is in orbit somewhere between 5,000 km and 15,000 km above the earth’s surface. MEO satellites are similar to LEO satellites in functionality. MEO satellites are visible for much longer periods of time than LEO satellites, usually between 2 to 8 hours. MEO satellites have a larger coverage area than LEO satellites. MEO:-

MEO contd.:

MEO contd. Advantages:- A MEO satellite’s longer duration of visibility and wider footprint means fewer satellites are needed in a MEO network than a LEO network. Disadvantages:- A MEO satellite’s distance gives it a longer time delay and weaker signal than a LEO satellite, though not as bad as a GEO satellite.

Thank you:

Thank you