The Federal Communications Commission (FCC) is getting ready to publish a
notice of proposed rulemaking (NPRM) next month to seek comment on the
commercialization of upper millimeter-wave spectrum, a move that opens the
airwaves to multi-gigabit-per-second Internet speeds.
Spectrum for U.S. businesses in the 71-76 GHz, 81-86 GHz and 92-95 GHz
bands is under consideration, though FCC officials seem undecided whether
to license the spectrum or keep it open, like the 900 MHz, 2.4 GHz and 5.8
GHz bands used by 802.11b and fixed wireless providers today.
Steve Stroh, editor of the “Focus On Broadband Wireless Internet Access”
newsletter, said a case could be made both for and against keeping the
“The upside is that it would be much simpler to make use of that spectrum,
(there would be) no coordination needed, no payment of fees to use the
spectrum, and no long wait time for authorization of a link,” he
said. “With more usage generally comes cheaper equipment.
“But there are potential problems,” Stroh added. “Going license-exempt
means there’s no expectation of interference protection and that may be a
big issue — and subsequently no expectation of enforcement by the FCC if
there is interference.”
Given the nature of the upper millimeter-wave bandwidth, however, the case
for license-exempt status gets a boost, according to James Wolfson, vice
president at the National Spectrum Managers Association.
“The unique thing about (upper millimeter-wave bandwidth) is that it’s so
high-frequency the bands are very narrow, making discrimination off the
antennas very narrow, which — in turn — means the interference
possibilities or dangers are little to none,” he said.
The technology does have drawbacks. Because the bandwidth’s frequency is
so narrow, it is almost strictly a point-to-point technology, which means
you won’t be seeing any ultra-high-speed “hotspots” any time soon.
Another limitation is its attenuation problem, resulting in lost signals
during bad weather like fog and heavy rain. In that respect, the
technology is very similar to free-space optics, an existing technology
transferring large amounts of data at high-speeds using a low-powered
infrared laser. Wolfson said there is some talk about marrying the two
technologies together in the future, using each as a backup to the other
when one loses its signal.
Robert Primosch, a lawyer with the Wireless Ethernet Compatibility
Alliance, said the FCC’s inclination is to keep the spectrum free for all,
and avoid licensing issues altogether.
“My sense is that the FCC would prefer to go with the unlicensed model – I
don’t think they like the idea of using point-to-point licensing for this,
and auctioning this spectrum may not bring in much money and thus may not
be worth the trouble,” he said.
One company that does want the FCC to impose licensing is LOEA
Communications, the company responsible the expected NPRM. The carrier
filed a petition late last year, asking the agency to adopt service rules
for the 71-76 GHz and 81-86 GHz spectrums.
LOEA proposes a licensing process to ensure that
everyone abides by the FCC rules established in Part 101. Part 101 sets
rules for the use of microwave transmitters used by carriers and private