What is Citizens Broadband Radio Service (CBRS)? In the United States, RF spectrum bands ranging from 3.5 GHz to 3.7 GHz are referred to as Citizens Broadband Radio Service or CBRS. The Federal Communications Commission (FCC) in the United States has designated that this CBRS spectrum be managed by the CBRS Alliance and shared among three tiers of users: incumbent access users, priority access licenses (PALs) and generally authorized access (GAA) users. Incumbent users include military and fixed satellite stations. PALs include operators who must acquire their spectrum block through spectrum auction (licensed spectrum). The GAA tier is comprised of unlicensed spectrum available for use by anyone, free of charge. To learn more, read our blog ‘RF and 5G new radio: top 5 questions answered’.