April 2004
Microwave Evolves Into Viable Broadband
Internet Access
BY GRAHAM BARNES
This article looks at the current state of the broadband industry with a
focus on broadband wireless � the long-awaited �third pipe� (the first two
�pipes� being telco copper phone lines and cable TV co-ax systems). Telco
copper phone lines offer a ubiquitous presence, but they are owned � lock,
stock and barrel � by monopolies that cannot easily deploy the latest
technology and that charge a hefty fee for their access. Cable TV co-ax
lines offer a competitive alternative, and are being upgraded to fiber
(albeit at a slower rate in the current economy) but do not serve many homes
nor most businesses. Fixed wireless has seen the failure of a number of
high-profile licensed microwave attempts, including Winstar, Teligent, ART
and Ricochet. So, we are still left with an unmet need � and a major
opportunity � for a competitive alternative to deliver broadband Internet
across the U.S.
SO, WHAT�S NEW?
Is there anything truly new and competitive for the industry? The answer
is a resounding �Yes,� which comes, perhaps unexpectedly, from the most open
and free part of the broadband industry � unlicensed fixed wireless. There
are four parts to this exciting story. First of all, unlike the higher
profile licensed microwave providers mentioned above, it is the unlicensed
wireless broadband operators who have survived the recession. Some of these
unlicensed operators are now evolving successfully from small local
providers into major regional players, and there is renewed talk of
consolidation plays. Second, regulators are enjoying the opportunity to
increase deregulation and reduce their costs by embracing unlicensed
operation to such an extent that the FCC has finalized a quiet, yet major
deal with the DoD (Department of Defense) to release 225 MHz of valuable
spectrum real-estate for unlicensed operation. Third, end users are gaining
confidence in wireless service so that it is no longer as difficult to
convince IT managers and CFOs to put their trust in an intangible medium
like wireless. Finally, a hot new technology is developing to allow vendors
to offer smart new radios to the unlicensed service providers, which may
finally fulfill the long-unmet promise of interference-free
interoperability.
HOT NEW TECHNOLOGY?
When unlicensed operation was initially proposed by a government
think-tank called the Mitre Corporation, the idea was to use military spread
spectrum technology for US commercial applications. The U.S. military used
spread spectrum to avoid detection and jamming of its transmissions from the
enemy. Therefore, Mitre thought that this technology could be the solution
to allow new commercial services to enter and operate in existing spectrum
currently allocated to other services, on a secondary basis without causing
or receiving any interference. Otherwise, it seemed there was no new
spectrum available for new services. So, in 1989 the FCC set up special
rules under Part 15.247 allowing shared operation on an unlicensed basis in
the 900 MHz, 2.4 GHz, and 5.8 GHz ISM (Industrial, Scientific, and Medical)
microwave bands and eventually manufacturers started developing initial
equipment to take advantage of this windfall.
Some of the manufacturers started looking at different applications from
those indoor devices originally intended by the FCC, and ended up developing
products for use outdoors with megabit throughput capacities. Various
service providers and enterprises deployed these products to replace telco
1.54 Mbps T1 lines with lower cost, wireless links under their own control.
In order to provide the megabit throughput capacity within the FCC
designated spectrum, the designers were forced to use far less spreading
(hence process gain) in these products than used in the military
applications. In turn, this meant that the wireless links weren�t all that
resistant to interference and the initial interference-free promise of the
hot new technology did not really materialize for this application,
especially when compared to licensed microwave links. However, it did spark
the desire by smaller service providers for unlicensed microwave products to
provide broadband Internet access using wireless technology.
REGULATORS LOVE UNLICENSED SPECTRUM!
The next step in the story was the release of the UNII (unlicensed
national information infrastructure) bands at 5 GHz by the FCC. UNII was in
theory intended for broadband wireless Internet use, but this time it was
co-opted for wireless LAN service using IEEE 802.11 standards. The key to
understanding this is that (i) UNII rules deleted any spread spectrum
requirement, and (ii) all LANs (including wireless LANs) operate behind
enterprise/user firewalls and routers, thus still requiring an external
Internet connection � usually DSL, T1 or cable! So, �round 2� by the FCC was
still really a strikeout as far as broadband wireless Internet was
concerned.
Now, this is where the technology story gets particularly interesting. In
2003, following a proposal by WECA (Wireless Ethernet Compatibility
Alliance), a group of wireless LAN vendors, the FCC opened negotiations with
the DoD to expand unlicensed operations in the UNII bands by a further 225
MHz by sharing adjacent spectrum currently in occasional use for RADAR
services. The FCC wanted to do this because they faced the twin tasks of
trying to regulate valuable spectrum in a climate of tight government
spending on non-defense budgets and also the growing demand from
manufacturers for regulations allowing them to increase production and
compete worldwide in the current economic recovery. By pursuing a spectrum
policy of increased access to unlicensed spectrum, the FCC not only solved
their internal limitations to regulate all of the frequency bands, but they
also positioned themselves as responsive to the requests from the wireless
LAN manufacturers, such as WECA.
The DoD stipulated certain tight, technical requirements, including DFS
(dynamic frequency selection) and TPC (transmitter power control) before
accepting the sharing proposal, because they knew that the previous UNII
rules did not really solve the problem of interference-free operation. The
DoD technical requirements are fairly easy to satisfy in the indoor wireless
LAN environment, but far harder to meet in the outdoor environment used for
broadband Internet access. Nevertheless, the FCC successfully pushed, not
only the DoD, but also all the different national regulators at last year�s
WRC-03 conference to approve the 5.25�5.35, 5.47�5.725, and 5.725�5.85 GHz
microwave bands for unlicensed use, both indoors and outdoors on a global
basis. This is clearly a win-win situation for the FCC. However, the FCC
understands that indoor wireless LAN devices are not the solution to
broadband Internet access. Nor are they blind to the claim that there is
still more wireless broadband Internet access in Korea, for example, than
there is in the United States!
The implication of all of this for the broadband industry is that fixed
wireless service providers may well be able to count on more of the FCC�s
support for unlicensed spectrum and regulation allowing them the freedom and
flexibility to deploy and grow their outdoor networks in the future,
unfettered by concerns that there will be insufficient spectrum resources or
outdated technical requirements to compete successfully with the first two
pipes � copper and co-ax.
WHAT IS �COGNITIVE RADIO�?
Currently, the FCC has issued several notices of proposed rulemaking (NPRMs)
that investigate the opportunities for increased flexibility in deploying
unlicensed equipment and the possibility of opening additional spectrum to a
new unlicensed technology that they call �cognitive radio.� Cognitive radio
is a term used to describe wireless technologies used to make radios aware
of the RF (radio frequency) environment in which they operate. Cognitive
radio technology includes algorithms, like DFS and TPC, which modify the
frequency or power of operation to avoid any signals with which they might
interfere. The opportunity now exists for vendors to develop next-gen
products that must not only be able to meet the new DFS and TPC requirements
and operate across the full new 5.25�5.825 GHz UNII band, but also uses
these requirements to spur the creation of related algorithms that finally
fulfill the long-unmet hype and promise of interference-free
interoperability. True �cognitive radios� are software-defined wireless
systems that achieve licensed microwave quality performance and reliability,
while still operating outdoors in shared, unlicensed bands without causing
any interference to others or being affected by other users of the shared
spectrum.
Vendor groups like Wi-Max are developing true �wireless WAN� products for
broadband Internet access, currently based on the IEEE 802.16 OFDM
(orthogonal frequency division multiplex) standard. These designs will need
to allow �always-on� connections and the reliable transport of demanding IP
applications such as VoIP, together with very low packet loss and latency.
IEEE 802.16 devices that incorporate cognitive radio technology will adapt
not only to interference, but also to multi-path caused by obstructions and
reflections on a real-time, per subscriber basis. Cognitive radio processing
should improve building penetration, and increase range and overall
coverage, while still being implemented in a low cost (<$300) CPE.
IS THERE A MARKET FOR BROADBAND?
The final part of the equation defines a viable broadband wireless market
consisting of successful service providers and enough consumers with the
confidence in the technology to pay for it. There is no doubt that Wall
Street is interested � but still not fully on board. There is also no doubt
that the business segment has been far more lucrative than the residential
segment, with much higher ARRPU (average recurring revenue per unit).
However, it is not surprising that large-scale wireless broadband
deployments have crashed on the twin rocks of crushing debt and dubious
performance/reliability. As a result, most consumers still cannot expect to
find a brand-name broadband wireless provider with coverage in their area
yet.
One group of industry analysts, Parks Associates, recently issued a
report projecting that unlicensed wireless services would be a $2 billion
market in 2008, although much of that projection is assumed to be in the of
late high-profile hot-spot segment, although it is currently unsuccessful
and lacks revenue. In fact, there are still relatively few unlicensed fixed
wireless broadband regional players, emerging in different parts of North
America, who have achieved the critical mass necessary to support multi-city
coverage area and still deliver reliable, high-quality services � despite
using the current generation of hardware. These emerging regional providers
have proven customer references who love the speed, flexibility, pricing,
and service levels of broadband wireless. These players, and the technology,
are poised for explosive growth as the economy rebounds, next generation
equipment ships, and financial markets wake up to the potential of
broadband.
Graham Barnes is CEO of NextWeb, Inc., a broadband network service
provider delivering local access and advanced IP applications to corporate
users over its next-generation fixed-wireless network. For more information,
please visit www.nextweb.net.
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