 Hello everyone, Myself, K. R. Biradhar, Assistant Professor, Department of Electronics and Telecommunication Engineering, Walchand Institute of Technology, Swalapur. Welcome to a video lecture on types of satellite orbits. Let us start with the learning outcomes first. At the end of this video you will be able to classify different types of orbits, discuss advantages and disadvantages of different orbits. In this video we shall see what is orbit and what are its types. An orbit is a regular repeating path that an object in space takes around another one. Here object refers to satellite and it revolve around the earth. The simple way of defining the orbit is the path followed by the satellite is called an orbit. Arbids can be classified depends on the shape and position. First we shall see the classification of orbit on the basis of shape. First one is equatorial orbits, see the diagram polar orbits and inclined orbits and it is not shown in the diagram. The orbit which is just above the surface of earth's equator is called equatorial orbit. All the geo-satellites are placed in equatorial orbit since the speed of earth is same as geo-satellite speed. Polar orbit is the orbit which is just above the surface of polar region of the earth. If the satellite is in inclined orbit means when the orbit exhibits an angle other than 0 degree to the equatorial plane, this angle is called the orbits inclination. Arbids are classified on the basis of altitude are geo-synchronous satellite orbit, low earth orbit, medium earth orbit and malny orbit. See this diagram it consists of different orbits and also with the distance from the earth. Geo-satellites are placed at furthest distance from the earth also geo-satellites revolve in equatorial plane of the earth and these satellites are used for wireless communication. Leo-satellites are placed nearest to the earth compared to other satellites and these are used for capturing the image of the earth. What the meo-satellites are orbiting the earth between Leo and Geo. A malnia orbit is a type of satellite orbit and it is designed to provide communications and remote sensing coverage over high latitude. Geostationary earth orbit that is also called geo-satellites are placed at an altitude around of over 35000 kilometer above the earth surface along the equator and complete one revolution around earth precisely every 24 hours. Geo-satellite revolve around the earth at the same speed as the earth rotates. Geo-satellites remain in the same position relative to the surface of earth. Geo-satellites are at greater height it covers large geographical area. Hence, only three satellites are required to cover the entire earth. Geo-satellites are visible for 24 hours continuously from single fixed location on the earth. Geo-satellites are ideal for broadcasting and multi-point applications. Since these satellites are visible for 24 hours fortunately ground station tracking is not required less number of satellites are needed to cover the entire earth. This advantage of Geo the signal requires considerable time to travel from earth station to satellite and vice-versa. Due to this the received signal is very weak better LNA modem increase cost of ground station. Due to longer signal transmitting distance the received signal is very weak better low noise amplifier and modem is required for ground station. This increase the cost of ground station equipments. Due to longer transmission the signal introduces more propagation delay in the network. Geo-satellites are not suitable for point to point communication. Geo-satellites provides poor coverage at polar region low earth orbit that is also called LIO. Geo-satellites are much closer to the earth ranging from 500 to 1500 kilometer above the earth surface. Geo-satellites do not stay in fixed position relative to the surface and are only visible for 15 to 20 minutes each pass. Geo-satellites revolve with very high speed and speed of these satellites are faster than earth speed. Therefore, range of focusing any particular place on the earth surface is only 15 to 20 minutes per each pass that means each satellites revolution. A network of LIO-satellites is necessary for LIO-satellites to be useful. The LIO-satellite is useful it must have a network associated with it. Geo-satellites of LIO-satellites are near to earth provides better signal strength. Since LIO-satellites are closer to earth the communication between satellite and ground station will have a better signal strength. Less power is needed for transmission that means it is only about 1 watt power is sufficient for transmission. It has least propagation delay compared to other orbits. In LIO the signal transmission delay or propagation delay is very less. Low cost equipments are sufficient for ground stations better frequency use due to smaller food friends. Disadvantages of LIO smaller distance from earth it covers less reason. LIO-satellites are placed at small distance from earth so that it covers small reason of earth surface. Large number of satellites are needed to cover. In LIO large number of satellites are required to cover the given area. LIO-satellites are visible only for 15 to 20 minutes from particular area of the earth. Less time for maintenance like testing, troubleshooting, etc. LIO-satellites have shorter lifespan usually 5 to 8 hours years compared to LIO. Medium earth orbit that is also called MIO. MIO-satellite is in orbit somewhere between 8000 to 18000 kilometer above the earth surface. MIO-satellites are similar to LIO in functionality with respect to function is concerned MIO and LIO are same. Visible for much longer periods of time usually between 2 to 8 hours. This means MIO satellites are visible for around 2 to 8 hours from earth surface. MIO-satellites have a larger coverage area than LIO-satellites. Coverage area of MIO-satellites are larger than LIO and smaller than GEO. Advantages of MIO. MIO-satellites are placed at higher altitude compared to LIO-satellites. Less number of MIO-satellites are needed to cover entire area of the earth. MIO-satellites requires slightly higher transmission power compared to LIO-satellites. MIO-requires reduced latency compared to GEO-satellites. MIO-maintains a footprint well suited for regional networks. Disadvantages of MIO. The signals become weak when they reach earth from MIO compared to LIO. This is due to higher altitude of MIO in comparison to LIO. Hence more transmit power is needed to cover path loss and other attenuating atmosphere. MIO-satellites are visible for only 2 to 8 hours from earth. Hence satellites are required to be tracked from the earth due to their rotation. The system is more expensive compared to LIO. Multiple MIO-satellites are needed to cover the region continuously. MOL-nia-orbit-satellites. MOL-nia-orbit is basically an elliptical orbit and in MOL-nia-orbit the satellites remains in a nearly fixed position relative to earth for 8 hours. There is a series of three MOL-nia-orbit-satellites can act like a GEO-satellite. MOL-nia-satellites are useful in near polar regions. This slide refers to think and answer. Write one measure use of GEO-orbit-satellite and LIO-orbit-satellite. Pass the video and write your answer. I think you might have written the answer. The measure use of GEO- and LIO-satellites are. GEO-orbit-satellites are used in wireless communications. LIO-orbit-satellites are used in capturing image of earth. These are the references used to prepare the above PPT. Thank you.