Monday 2 June 2008

LTE v/s WiMax

In my last blog “LTE Latest News and Status” I wrote how LTE is developing as a technology how some companies are choosing LTE over WiMax.
But we still have a long way to go before it is clear that which technology will be the winner in the race of 4G.
Every now and then the trends are occurring in which one technology being preferred than the other.
But some of the recent developments have once again suggested that WiMax as a technology can’t be taken as lightly and is providing seriously competition for LTE.

WiMax already has a first-mover advantage over LTE. It is possible that WiMax could prove to be the winner in the 4G race against LTE (Long Term Evolution) simply because the technology is here, first.
Teresa Kellett, director of global development for telco Sprint Nextel, said during a panel discussion at WiMax Forum Asia 2008 that WiMax's first-mover advantage over LTE may help the former become a more widely-adopted technology eventually.

LTE is touted as the successor to the existing UMTS (Universal Mobile Telecommunications System) 3G technology, capable of supporting significantly faster data rates.
Comparing the two competing technologies to another pair of competing standards--GSM and CDMA--she said GSM is the dominant cellular technology globally because it was first to market. CDMA, on which Sprint Nextel operates, has a stronger footprint in the United States.

"The head start a technology has is the key differentiator," said Kellett.
Another panellist, Scott Wickware, vice president of carrier networks for Nortel, said the exchange of knowledge is also beneficial to current players in the market in helping them in areas such as establishing business plans.
"This is the first time I'm seeing so much cooperation in the industry, so it's good to be a first mover," said Wickware.

Recent trends in the industry are showing that when some big gun like Nokia, Ericsson are choosing LTE then WiMax as a technology also has something to relish when it sees that Intel is in their camp.

But together with the competion between the two technolgies, both the camps also realise that to survive and instead of killing each other they might be complementary to each other and move towards the convergence.

Garth Collier, managing director, of Intel's WiMax division for Asia-Pacific and Japan, said he is "seeing for the first time a convergence in the cellular industry".
Collier raised the point of WiMax and 3G being complementary and the possibility of co-existence.

While the market waits for LTE, WiMax will serve as a "data overlay" for 3G, meant for delivering data where 3G's speeds are inadequate, while the cellular network continues to handle voice well, he said.

The emergence of dual mode or dual band devices is most likely to happen in the "early days" as the industry in developed markets embraces 4G technology, he said. Raising the example of Korea, he noted the availability of models which combine both HSDPA (high-speed downlink packet access) and WiBro functionality.

In an interview with ZDNet Asia, Wickware said he expects WiMax to find its place as a more cost-effective and quicker way for providers to turn on broadband in rural areas without having to lay physical copper or fibre infrastructure to homes.

This concept is not just contained to emerging markets. "Even in developed countries, there are pockets where coverage is not good, where the operators have not had a business case to provide standard broadband," said Wickware.

Furthermore, the ecosystem is growing, he said. "When you consider that companies such as Intel are very much backing WiMax, it is not a stretch to imagine many of the PCs or consumer electronics devices will drive the deployment of WiMax in developed urban areas, too," said Wickware.

LTE camp sees this competition and trying very hard to complete 3GPP specifications for LTE (36 series comprise of LTE specifications).In the recent RAN meeting in Kansas, USA (May 5 – 9 2008) it was concluded that most LTE specifications are about 95% ready (RRC about 80%).

So LTE is not keeping itself far behind and only time will tell who will score the goal in this extra time or the match might go to penalties.


Ashwin said...

Does Mobile WiMax have a provision for backward compatiility with the existing cellular networks?

Also can you please comment on the backward compatibility of LTE with the existing 3G networks. I read an article which says providing backward compatibility in an LTE network is difficult as it has a different RAN architecture from 3G/3.5G networks..

Devendra Sharma said...

There is certainly a backward compatibility with the fixed WiMax.
I know that the IEEE is working on 802.16m, a protocol that promises WiMAX speeds of up to 1Gbps and backward compatibility with 802.16e-2005 or Mobile WiMax.
The proposed “Gigabit WiMax” standard will employ multiple-input/multiple-output (MIMO) antenna technology but the arrays will be larger to boost bandwidth. Cellular companies are banking on the new spec to
enable “convergence” as it would combine two parallel streams of wireless technology, i.e., 3G and 802.16. The protocol could also allow wireless providers to offer a range of services similar to those by wired networks, including video streaming, IPTV, and VoIP.

As for LTE there is definitely a huge focus on backward compatibility and the LTE camp can say with an authority that there will be backwards compatibility with the LTE devices.

The current LTE/SAE architecture already has the interfaces defined for handovers between two radio access technologies (LTE to 3G etc)
Access to all these various air interfaces will be done on the device side through multimodal chips.

Qualcomm announced in February it was expanding its device and base station chipsets to include LTE along with UMTS and CDMA2000.
The chipsets will allow backward compatibility to legacy UMTS and CDMA2000 networks for carriers that deploy LTE.
The new family of Qualcomm MDM9xxx-series LTE device chipsets will include:
• MDM9200™ chipset designed to support UMTS, HSPA+ and LTE
• MDM9800™ chipset designed to support EV-DO Rev. B, UMB and LTE
• MDM9600™ chipset designed to support UMTS, HSPA+, EV-DO Rev. B, UMB and LTE

Bodyweapon said...

That's interesting. QCOM 9K series still supports UMB... I thought they have given up on this.

Ashwin said...

Thanks for the clarification..