U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.


Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


The 3650 – 3700 MHz service was first created in 2005 when the FCC revised its rules to open the 3650-3700 MHz band for terrestrial wireless broadband operations. Under the licensing mechanism adopted for the band at the time the Commission issued and unlimited number of non-exclusive nationwide licenses to non-Federal entities for the 50 megahertz of spectrum allocated for commercial use. Those licenses served as a prerequisite for registering individual fixed and base stations.

In 2015, the Commission established a new Citizens Broadband Radio Service for shared wireless broadband use of the 3550-3700 MHz band (3.5 GHz Band). See Citizens Broadband Radio Service (CBRS). The new rules adopted for the CBRS service encompass the existing 3650 – 3700 MHz band. Under the Commission’s order existing 3650 – 3700 MHz band operations are grandfathered for up to 5 years. The Commission directed the Wireless Telecommunication Bureau (WTB) and Office of Engineering and Technology (OET) to issue a public notice seeking comment on the appropriate methodology for defining the grandfathered wireless protection zone contours. A Public Notice requesting comment on the methodology for defining the grandfathered wireless protection zone contours was released on October 23, 2015. On August 19, 2016 WTB and OET released a Public Notice announcing the final methodology for defining the grandfathered wireless protection zone contours.

In order to receive grandfathered protection, incumbent licensees were required to file supplemental information regarding their registered stations see Public Notice.  The WTB configured a cloud based platform to facilitate the collection of that information which was launched for a four month window ending August 7, 2017.   The window for filing the supplemental information is closed.   Licensees in the 3650-3700 MHz who did not meet this deadline may continue to operate, but will not be afforded protection from interference caused by new CBRS operations.   Grandfathered registered sites are afforded protection until April 17, 2020.    After the transition, Grandfathered Wireless Broadband Providers will have the option, available to all eligible 3.5 GHz Band users, to operate on a GAA basis consistent with Part 96 rules throughout the 3650–3700 MHz band.



Tuesday, March 12, 2019