The need for a migration path to LTE sounds like surrender for WiMAX, but the technology’s supporters are fighting on

Posted by Julian Bright Wednesday, June 23rd, 2010

Add a comment

A number of high-profile setbacks in recent weeks have further dented the already weakened
business case for WiMAX.
In a widely anticipated move, Russian operator Yota revealed plans in May to switch tack and
start rolling out LTE. The company, which has always preferred to describe itself as a mobile
broadband provider rather than a WiMAX operator, had been rumored for some time to be
contemplating the change. It will start to deploy LTE networks in five cities later this year.
India’s 2.3GHz-spectrum auctions dealt WiMAX a second blow when it emerged that the list
of successful bidders is dominated by companies pledged to launch services based on the TDD
version of LTE. Among the successful bidders was Qualcomm – a longtime critic of WiMAX –
which secured prime TDD spectrum covering Delhi and Mumbai, and Reliance-owned Infotel
Broadband Services, which secured spectrum in all regions.
It now appears that the Indian market, which had looked like the next great hope for WiMAX,
might go the LTE route.
The decision by Netherlands-based WorldMax to close down its service in Amsterdam
just two years after launch – due to license restrictions imposed on the company by the
Department of Defense over interference concerns – removes another torch-bearer for
WiMAX from the market.
With the long-term prospects for WiMAX looking increasingly uncertain, it was always going
to be challenging for the WiMAX Forum Global Congress – held June 16-17 in Amsterdam,
Netherlands – to strike an upbeat note.
Forced to acknowledge LTE’s growing dominance, successive speakers emphasized its lack of
market-readiness, particularly with regard to TD-LTE technology, which poses the most direct
challenge to WiMAX. Banking on a delayed entry of TD-LTE into the market, the speakers
urged operators to deploy WiMAX to win market share in countries hungry for increased
broadband penetration, such as India.
Stressing the relative maturity of WiMAX, a number of speakers at the conference claimed
that the development of TD-LTE is running as much as a year behind that of FDD-LTE. It is a
claim that LTE’s supporters would probably contest, given evidence of the effort behind TD-LTE
in 3GPP, the technology trials conducted recently by China Mobile and the multivendor TD-LTE
technology demonstrations at the recent Shanghai Expo, all of which point to the likelihood
that TD-LTE will be commercially ready around the same time as, if not sooner than, the FDD
version.
Regardless of TD-LTE’s readiness, however, the WiMAX community has to make some serious
concessions before it can secure backing for more network rollouts. It emerged at the
Amsterdam event that would-be investors and operators alike are seeking assurances that
WiMAX networks are capable of migrating to LTE sometime in the future. WiMAX vendors
are therefore eager to point out that the equipment they supply today can, at some future
date, be converted to TD-LTE by means of a software upgrade.
Meanwhile, efforts continue to enhance the performance of existing WiMAX networks and
to develop next-generation 802.16m products. The current 802.16e technology is being given
a performance boost by incorporating elements of 802.16m, in a bid to improve capacity and
coverage. Among the first to adopt the enhancements is Japan’s UQ Communications, which
reports significant gains in throughput in both the uplink and downlink.But with only a small number of vendors backing 802.16m, or Phase 2 WiMAX, there must
be some doubt as to whether the technology can be commercialized late in 2011 as hoped.
The risk to 802.16m is that the availability of TD-LTE, also in late 2011, might make that the
preferred technology route for WiMAX operators.
The 4G debate
Of more immediate concern for US operator Clearwire, the world’s largest WiMAX provider, is
a marketing challenge from T-Mobile USA, which says its recently expanded HSPA+ network is
capable of delivering “4G speeds.” T-Mobile says the Clearwire network offers limited coverage
and inferior data rates to its own HSPA+ network – a claim supported by various user blogs –
though WiMAX providers such as Clearwire can point to their larger allocation of spectrum
as being crucial in the delivery of a “4G-like” experience.
T-Mobile’s marketing spin does, however, raise the broader question of what WiMAX
providers will call 802.16e Enhanced. The unchecked use of the term “4G” for WiMAX and
now 3.5G networks – and no doubt a number of the upcoming LTE networks – has already
gone a long way toward undermining the ITU’s assertion that the candidate technologies for
IMT-Advanced – likely to be LTE-Advanced and potentially WiMAX 802.16m – are correctly
termed 4G. These are expected to be capable of delivering 100Mbps and above in a mobile
environment and 1Gbps when stationary – well above the capabilities of today’s networks.
A T-Mobile spokesman told Informa Telecoms & Media that the use of 4G with reference to
HSPA+ was not technically correct but said that the term was being used on performance
grounds, in response to the marketing of WiMAX services. By the time IMT-Advanced
becomes a reality, however, the marketers might well have moved beyond “4G” to “4.5G”, or
even “5G.”