Small Cells Rulemaking: 3550-3650MHz - Citizens Broadband Service (CBS) January 04, 2013 14:57

Interesting facts from the Small Cell Rulemaking.  A signal at 3.5GHz would have 29% reduced range compared to BRS/EBS (2.5GHz), 45% compared to PCS (1.9GHz) and 75% compared to the Cellular (850MHz) bands.

Half of this band is currently used for receive frequencies for earth/satellite stations in 37 cites and adjacent radar systems exist from 3650-3700MHz.

There will be large exclusion zones due to incumbent use of the spectrum.  West Coast, East Coast, Gulf Coast, Hawaii, and Guam. Approximately 190 million people or 60% of the US population would not have access to small cell technology in the 3.5GHz band.  From the map below, the only Top 10 markets that could use this frequency band would be Chicago and Detroit with Detroit being a question mark due to issues with Canada.

FCC 12-148A1 - Figure 2


FCC Small Cell Definition
Small cells are low-powered wireless base stations intended to cover small indoor or outdoor areas ranging in size from homes and offices to stadiums, shopping malls, and metropolitan outdoor spaces. Small cells are typically used to extend wireless coverage to areas where macro cell signals are weak or to provide additional data capacity in areas where existing macro cells are overloaded. Small cells are also characterized by their inclusion of novel sensing technologies such as environmental recognition and auto-configuration. (Paragraph 30, FCC 12-148A1)

The FCC has proposed a multi-tier licensing framework:
  • Incumbent Access - federal and grandfathered Fixed Satellite Service (FSS) providers
  • Priority Access - critical services including hospitals, utilities, state, and local governments
  • General Authorized Access (GAA) - commercial, opportunistic users as well as business and homeowners.  GAA users would be required to register in the SAS.
A Spectrum Access System (SAS) similar to the Television Whitespace Database used to coordinate unlicensed usage of the UHF broadcast TV whitespace. SAS would manage CBS access and ensure that lower tiered users will not harm federal and FSS users.