Satellite communication is achieved using radio signals and satellites, and these tools transfer information to different places. The satellite act like a mirror and radio signals are directed by the satellites to different places. Satellite communication are available in different types and this varies according to the signal and satellite used for the purpose.

 

Image via Wikipedia

First simple type is the passive communication where the satellite reflects the radio signal to a new location on the earth. This passive communication is chiefly used for multiple accesses and it does not produce damage because of electronic failure. Also, this type of communication system uses wide bandwidths. This system is not mostly used as it does not amplify the signal.

Active satellite communication system is another type that amplifies the radio signal before directing to another location on the earth. In this type of communication, satellite acts as a repeater and also the signal strength is greater than the passive type. In this model, terminal located on the earth sends the signal for amplification to the satellite and this procedure is called up-link. Transmitting amplified signal back to the earth is called down-link. Many services like Radio, Internet, direc tv and what not, are using satellite communication and pushing the limits of technology further.

Global positioning system is a well-known communication system that is used to position a place or person on the earth. This system uses different satellites for positioning and the signal is normally send to a GPS tracker or receiver. To locate the position, minimum three satellites need to transmit the signal to the GPS receiver. Thus different communication system is useful for different sectors.