A spot beam is a sharply focused radio beam from a parabolic antenna with a small beam angle. Spot beams are emitted by High Throuput Satellites( HTS) with multibeam technology, among others.
Such a spot beam of a satellite has an extremely narrow radiation characteristic and radiates only on a small, geographical part of the earth's surface. It covers several hundred kilometers. In contrast, the radio beam of a satellite with a single beam covers several thousand kilometers.
Such radio beams are generated by pencil beam antennas. The field strength received by these antennas is much higher than that of a global beam. The receiving equipment is therefore smaller and lighter and achieves better transmission quality. Another advantage is more efficient frequency utilization, since the same transmission frequency can be used several times in other spot beams. This is referred to as frequency reuse.
Spot beams are used in satellite Internet, where they irradiate a small hot spot on the earth's surface from satellites.