The S band is part of the microwave band of the electromagnetic spectrum , which is the standard set by IEEE for radio waves . The frequency range of the S band is 2 to 4 GHz , which exceeds the conventional boundary between UHF and SHF , which is 3 GHz. The S band is mainly used by NASA for surface communication radar systems , weather radar and various communications satellites such as communications with the International Space Station and the space shuttle .