fixed wirelessThe FCC will vote next month on a Spectrum Horizons proposal that could eventually open up spectrum at extremely high frequencies for mobile use. Previously this spectrum was considered unsuitable for telecom services but as wireless bandwidth demand continues to climb, network operators are exploring higher and higher frequencies.

As FCC Chairman Ajit Pai explained in a blog post, “recent advancements in propagation technology have changed the equation and expanded the boundary of usable spectrum.”

The proposal takes the form of a notice of proposed rulemaking seeking input in three different areas, including rules for fixed point-to-point use of up to 102.2 GHz in various bands, whether to make up to 15.2 GHz of spectrum available for unlicensed use in several band segments and creating a new category of experimental licenses for the 95 GHz-3 THz range.

In telecom we’re not accustomed to reading about the THz spectrum band, but 3 THz is equivalent to 3000 GHz.

Spectrum Horizons Proposal
The rules for fixed point-to-point operations would apply to spectrum in 17 bands between 95-275 GHz. The rules would be based on those that currently apply to the 70/80/90 GHz band. According to the draft NPRM, key elements of these rules include:

  • The FCC would issue non-exclusive nationwide licenses for 10-year terms
  • Each fixed point-to-point link would be registered through a system maintained by a database manager.
  • Applicants would be able to request licenses for any portion of any band
  • Links would have to be constructed within 12 months of their registration
  • Interference protection would be granted to the first-in-time registered non-federal link

The 15.2 GHz of spectrum for unlicensed use would be in four frequency bands:

  • 122-123 GHz
  • 244-246 GHz
  • 174.8-182 GHz
  • 185-190 GHz

As for the experimental licenses, the FCC noted in a draft of the NPRM that “while our existing [Experimental Radio Service] rules have been very beneficial in encouraging experimentation below 95 GHz, we believe that they may be overly restrictive for the largely uncharted spectrum range above 95 GHz.”

Accordingly, the commission said it would “seek ways to liberalize the rules in that range by permitting a longer license term and increased ability to market experimental equipment and use available frequencies over broad geographic areas.”

In his blog post, Pai said, “If we broaden our nation’s spectrum horizons, we’ll keep the United States in the lead when it comes to technological innovation.”

Image courtesy of flickr user Stefano Brivio.