Differing amounts of power are required depending on the application. For example, direct TV broadcasting uses higher power transmitters as the residential receiver equipment is relatively simple. Often a dish as small as a 45 cm is used to receive the satellite signal. At the other end of the spectrum KPN for instance uses 34 metre dishes to receive international traffic, which are more efficient in capturing even weak signals. The footprint of a satellite is the area on earth that is covered by the signal of the satellite.
Most modern satellites use several spot beams.
Spot beam technology makes it possible to concentrate the satellites signals on several smaller areas within the global beam. Apart from a more efficient use of frequencies, spot beams are also used to concentrate the satellite signals to areas where traffic is expected to be generated. Thanks to spot beam technology a stronger signal can be received on earth, which makes it possible to reduce the size of the antennas of satellite terminals. The development of the Inmarsat mini-M telephone became possible with the use of spot beam technology. Low orbiting satellites have much smaller footprints.