S-band

The S band is part of the microwave band of the electromagnetic spectrum. It is defined by an IEEE standard for radio waves with frequencies that range from 2 to 4 GHz, crossing the conventional boundary between UHF and SHF at 3.0 GHz. The S band is used by weather radar, surface ship radar, and some communications satellites, especially those used by NASA to communicate with the Space Shuttle and the International Space Station. The 10 cm radar short-band ranges roughly from 1.55 to 5.2 GHz.

In the U.S., the FCC approved satellite-based Digital Audio Radio Service (DARS) broadcasting in the S band from 2.31 to 2.36 GHz, currently used by Sirius XM Radio. More recently, it has approved for portions of the S band between 2.0 and 2.2 GHz the creation of Mobile Satellite Service (MSS) networks in connection with Ancillary Terrestrial Components (ATC). There are presently a number of companies attempting to deploy such networks, including ICO Satellite Management and TerreStar.

The 2.6 GHz range is used for China Multimedia Mobile Broadcasting, a satellite radio and mobile TV standard which, as with proprietary systems in the U.S., is with the open standards used in the rest of the world.