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The third quarter looks set to be the turning point
for WiMAX, seeing the release of a new version of the
standard that will significantly boost silicon roll-out.
Carrier interest, critical to success, is rising and
British Telecom is the latest major telco to say that
it will carry out trials, following in the footsteps
of AT&T and Nextel. But significant spectrum and interference
issues need to be addressed if WiMAX is to reach its
full potential.
With two major events focused on the standard running
last week, an increasing number of equipment companies,
including Siemens Mobile, were also laying down roadmaps.
Siemens will work with Intel on base stations and on
future mobile devices incorporating Wi-MAX. Intel, as
usual, dominated the agenda at both meetings – the WiMAX
Forum’s own summit and the WCA Annual Symposium, both
in San Jose. Broadband
wireless and ADSL providers will bring the next
five billion users to the #Internet, said Sean Maloney,
the high profile general manager of Intel’s Communications
Group and WiMAX’ chief ambassador. The cost effectiveness
of 802.16 means that "WiMAX-certified systems will provide
the building blocks truly to usher in the broadband
wireless revolution."
"We see a three-phased deployment of 802.16 technology
that will begin with fixed outdoor antenna installations,
quickly bringing wireless to emerging markets and speeding
the installation of broadband services without the need
to lay wire or cable," said Maloney. "The technology
will then rapidly progress to indoor antenna installations,
broadening its appeal to carriers seeking simplified
installation at user sites. Finally, in the third phase,
WiMAX certified hardware will be available in portable
solutions for users who want to roam within or between
service areas."
At this stage, Intel will have WiMAX Centrino-style
chipsets for handsets that connect directly to the antenna,
but for the coming 18 months it will focus its marketing
activities on infrastructure rather than client systems
– though increasingly, its R&D will be working on the
WiMAX portable.
Chip and equipment makers are starting to roll out ‘pre-WiMAX’
gear that is ready to migrate to the standard, as well
as hardware based on the first iteration, 802.16a. However,
the real turning point will come with the finalization
of 802.16d, a revision to ‘a’ that brings together the
original line of sight 802.16 standard, its non-line
of sight successor 802.16a, and the 802,16b and 802.16c
extensions for quality of service, testing and interoperability.
This specification is more advanced than ‘a’, especially
because it allows for smaller, cheaper power amplifiers,
bringing down the cost of implementation, and because
it supports smart antenna schemes such as Multiple In
Multiple Out (MIMO), which held maximize real world
range and power.
The new variant is now solid enough for first chips
to be designed in time for third quarter roll-out. The
revision was finished at the IEEE meeting in Vancouver,
Canada last week and a test suite will be ready in September.
Wavesat and Atmel are already working on 802.16d silicon
and UK-based Airspan Networks says it aims to be the
first to ship fixed wireless systems based on ‘d’. Its
kit will be based on Intel’s upcoming Rosedale WiMAX
chipset and Intel is also working with Alvarion, Aperto
and Redline. Fujitsu has also begun development of an
802.16d baseband in conjunction with Wi-Lan and two
Taiwanese chipmakers are expected to bring out early
WiMAX devices.
Mohammad Shakouri, VP of business development at Alvarion,
says the critical next step is to get the certification
process up and running. This is essential to win operator
trust after various high profile broadband wireless
failures of the past, such as Teligent, put many companies
off this sector. He points out that companies are now
shipping products that are compliant with 802.16a –
although he agrees that ‘d’ adds significantly to the
attraction of the standard – but they are not yet officially
certified as such, and so will be treated with caution
by possible telco customers, who would otherwise find
the low costs of WiMAX ($100-$150 per home for residential
services, and $5,000 to $30,000 per base station, Alvarion
says) attractive.
Although there is still considerable operator suspicion
to allay, more and more carriers are assessing WiMAX
as an alternative or parallel to wired or cellular networks.
Three operators, AT&T, Covad and PCCW, joined the WiMAX
Forum last week and more are expected to follow shortly.
BT and UK Broadband in the UK, Iberbanda in Spain, MVS
Net of Mexico, Brazil’s Neotec and Reliance Infocomm
in India are all planning or “serious considering” WiMAX
trials, according to Intel, which takes a strong role
itself in evangelizing Wi-MAX to operators and governments
worldwide. BT is one of the largest telcos so far to
take a public interest in WiMAX and is expected to roll
out trials in rural areas in the near future.
The WiMAX Forum admits that most of its work in 2003
was focused on chips and equipment and that there was
very little input from carriers. It aims to rectify
this with the formation of its Service Provider Working
Group, to encourage contributions from the carrier community
and to influence spectrum regulators. This should make
it easier for operators to influence the development
of the WiMAX system profiles, a process from which they
have complained of being excluded in the past, presumably
one factor in their slowness to become actively involved
until this month. Most importantly, the new group will
develop and promote the business case for service providers
to deploy 802.16; will focus on real world multimedia
applications; and will create standard network management
interfaces.
The aim is to gain greater carrier input at an early
stage in order to shorten the trial and review process
and reduce time to market. To improve carrier confidence,
it is essential for WiMAX to work with all the major
radio standards and their governing bodies. Action to
prevent collision with other wireless technologies and
to ensure that WiMAX can be rolled out consistently
in different countries is becoming urgent as products
approach the market. This is the remit of the WiMAX
Forum’s Regulatory Taskforce, which also exists to lobby
for allocation of spectrum for WiMAX applications on
a country by country basis. One key task is to ensure
interworking where WiMAX shares spectrum with other
protocols, such as Wi-Fi at 5GHz and 3G in the MMDS
spectrum (2.5-2.7GHz).
For all the official line that WiMAX and Wi-Fi are complementary,
unless their two bodies work closely together, there
is potential for interference in the 5GHz band where
802.11a operates – especially for outdoor Wi-Fi products,
which tend to work higher up the band than indoor ones,
and therefore closer to WiMAX. Guidelines are essential
to prevent chaos from “serious contention”, says Paul
Senior of Airspan, and head of the Regulatory Task Force,
especially as both technologies develop. For instance,
802.16 transmits control data every 2.5ms, blocking
other users from its channel, and the Wi-Fi QoS extension,
802.11e, has a similar functionality, making it behave
more like WiMAX. This will be the first priority of
the Task Force, working with the Wi-Fi Alliance and
IEEE.
More ambitious is the need to work with regulatory bodies
to try to obtain the “best deal” for WiMAX operators-
for instance, lobbying countries where 802.16 frequencies
are reserved for other uses.
One obstacle is that WiMAX has both fixed and mobile
aspects, but these tend to be handled separately by
regulatory bodies, with mobile technologies limited
to specific bands. For instance, some countries treat
3.5GHz as fixed only, which could be a major restriction
on 802.16e, and an issue that needs to be sorted out
before that version of the standard appears in products
in about 18 months’ time. And others allocate 3.5GHz
only for satellite, although this can share happily
with broadband, as it does in the UK.
There are also limitations on usage of the 5.8GHz band,
particularly in Europe, that could constrain the range
and capacity – and so the appeal – of WiMAX if negotiations
with the region’s regulators are not successful.
In summary, like most wireless bodies, the WiMAX Forum
Task Force is pushing for consistency of spectrum allocation
across different regions and for cooperation among standards
groups to minimize the risk of interference as frequencies
become increasingly crowded. Such work will be as important
as the technical developments of the vendors to convince
the operators to ramp up their trials in the coming
months and so create the expected boom in WiMAX-based
services at the turn of the year.
© Copyright 2004
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