An unlicensed frequency range in the U.S., known as the Citizens Broadband Radio Service (CBRS). Introduced in 2015, the Spectrum Access System (SAS) architecture coordinates and dynamically shares 150 MHz of the 3.5 GHz spectrum in three tiers. Incumbent includes existing federal government and grandfathered satellite and wireless services. A Priority Access License (PAL) is assigned to licensees for three years, and General Authorized Access (GAA) is open to the largest variety of users, which may use the entire 150 MHz if there are no PAL users or incumbents.Sensors along the coast of the U.S. detect federal shipboard use and reallocate channels within the band. See 2.4 GHz band, 5 GHz band, ISM band and LTE Advanced.