ITU Radio Regulations
Satellite radio is defined by the International Telecommunication Union (ITU)'s ITU Radio Regulations (RR) as a "broadcasting-satellite service". The satellite's signals are broadcast nationwide, across a much wider geographical area than terrestrial radio stations, and the service is primarily intended for the occupants of motor vehicles. It is available by subscription, mostly commercial free, and offers subscribers more stations and a wider variety of programming options than terrestrial radio.