Tag Archives: PAL license

FCC Looks at CBRS Spectrum Rules

On August 16, the FCC issued a Notice of Proposed Rulemaking and Declaratory Ruling to take a fresh look at the rules for using CBRS (Citizens Broadband Radio Service). This is 150 MHz of spectrum between 3.5 GHz to 3.7 GHz. It’s an important spectrum that historically has been used for U.S. Navy radar and to download and upload data to satellites. In recent years the spectrum is widely used for wireless broadband.

This is a wide-ranging NPRM that looks at a long list of issues. It’s always fascinating when the FCC does this kind of investigation because it shows the complexity of spectrum regulation and management. Specifically, the NPRM looks at the following issues:

  • The FCC asks for ways to ensure that the Department of Defense gets full use of the spectrum when needed, which would mean clamping down on aggregate interference. This means enforcing zones where the spectrum is reserved for the military, plus shutting down commercial users from the spectrum when it’s needed by the military.
  • The FCC wants to better coordinate the use of CBRS spectrum with neighboring 3.45-3.55 GHz spectrum that follows different rules.
  • The FCC is asking if there should be a change in the deployment of the sensors deployed by Google and CommScope that are used to detect DoD use of CBRS spectrum – since the sensors can also cause interference for other users of the spectrum.
  • The NPRM looks at the applicability of the CBRS spectrum rules in Alaska, Hawaii, and other U.S. territories.
  • The NPRM wants to strengthen the requirements that users register radios and devices that are using the CBRS spectrum to make sure that devices are capable of following power limitation and other requirements.
  • The NPRM asks what should be done to align out-of-band emissions limits with the nearby 3.7 GHz spectrum to protect against spillover from neighboring spectrum bands.
  • The NPRM discusses enforcing the rule that radios and base stations must update the SAS database within 60 seconds of making any changes in the location or characteristics of a given radio.
  • The FCC wants to investigate using Time Division Duplex (TDD) synchronization near the edges of the spectrum band to better coordinate with nearby spectrum bands.

The most controversial question asked in the NPRM is about increasing the power levels of base stations and customer radios. Understanding this issue requires a little background. The military always gets priority to use the CBRS spectrum. Other than the military, there are two other classes of users of CBRS spectrum. Some companies purchased a priority access license (PAL) license during an auction that gives them top priority to use the spectrum between 3.55 and 3.65 GHz. Additional users can acquire general authorized access (GAA) authority to use the spectrum. A GAA user only has access to spectrum when it’s not in use by the military or a PAL license holder.

The proposal to increase power pits large carriers like AT&T and Dish against WISPs and smaller wireless carriers. AT&T and Dish would like to use the spectrum under PAL licenses to boost broadband capabilities for cellular and FWA uses. Increasing the power would mean a radio signal will travel further, which would create more interference with other license holders – and this would make it harder for GAA license holders to use the spectrum. Cellular companies have always tried to maximize their benefit in every spectrum band, and in this case they might have a good argument since they are basically asking that carriers that purchased the spectrum at auction should have better use of the spectrum.

The spectrum priority rules for CBRS are part of an FCC experiment to accommodate more users of spectrum. The bigger policy question being asked by the FCC is if a fully licensed spectrum owner should be given full-power use of the spectrum, instead of setting lower power limits to try to accommodate more users of the spectrum. The FCC is considering using this same management system for other spectrum bands, and it will be interesting to see how the FCC tries to balance the rights of auction license holders against others. The FCC is clearly in favor of allowing wide use of spectrum when possible, but it also doesn’t want to cheapen the value of spectrum auctions by given auction winners something less than full use of the spectrum they purchased.

I have to imagine that most of the comments to the FCC’s NPRM are going to involve this one issue, as wireless carriers try to position themselves to best use the spectrum.