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WiMAX Chip Companies Ponder the Future of 4G Networks
Key issues in evolving wireless networks to 4G, the WiMAX eco-system and next generation air interface silicon were addressed by four leading semiconductor companies at IEEE ComSoc SCV panel session. Intel's 4G Visionary also offers his views.
Abstract:
Four leading WiMAX semiconductor companies - Sequans, Beceem, GCT and Wavesat-
presented their outlook for 4G networks and related silicon at the May 13th IEEE
ComSoc panel session entitled, "Semiconductor Evolution to 4G: Mobile WiMAX, LTE,
and other 4G technologies." This article will summarize that session and include
additional comments from other experts on the journey to 4G mobile networks.
Before we dive deeper, let's consider what 4G actually means and network
operator challenges that are driving them to deploy 4G networks.
Backgrounder: 4G definitions and challenges ahead
- To the standards purist (like this author) 4G networks will be based on ITU-R IMT Advanced recommendations, which are not yet completed. It is expected that LTE Advanced (3GPP version 10?) and the 4G version of WiMAX (IEEE 802.16m) will meet the LTE Advanced requirements and will be accepted as 4G standards. For more on the purist's view of 4G, please see reference 3. below.
- Many others believe that the initial version of LTE (3GPP release 8) and Mobile WiMAX (IEEE 802.16e) are 4G network technologies, because they already have the key building blocks required by 4G: OFDMA, flat- all IP- network, fixed or mobile operation, MIMO, hybrid ARQ (Automatic Repeat reQuest- for repeat transmission of mis-received packets) at the PHY layer, multi-megabit speeds delivered to users, etc. Those folks say that only incremental advancements will be made in future ("official 4G") versions of the respective standard.
- China may have its own 4G standards as well, making for a very confused 4G world. For example, China Mobile is said to be planning for a TDD version of LTE that will be backward compatible with TD-SCDMA and GSM.
- Whatever you think 4G really is, the wireless network operators will be forced to move forward with their 4G deployments in the next two to four years. Why? The amount of mobile data and video traffic continues to explode and 3G networks (which are packet over TDM overlays) will not be able to handle the speed requirements of many simultaneous mobile data/video users. Data caps (e.g. bandwidth metering) will have to be instituted which will frustrate and annoy users.
Let's take a look at some of the challenges mobile network operators face on
their evolution from 3G to 4G networks. We have previously written that smart
phones and "all-in-one" gadgets are driving the need for more bandwidth and QOS.
This past week, AT&T CEO Randall Stephenson stated that networks were becoming
choked by increased smart phone data traffic. This dynamic is already
accelerating the movement to 3.5G mobile data networks and will eventually push
operators to 4G. Reason: 4G networks offer more bandwidth per user, are more
bandwidth efficient (e.g. OFDMA and MIMO), and are "all IP" packet based (vs.
TDM overlays). For more on how network operators might deal with the mobile data
explosion, please see reference 4. below.
Notebooks and netbooks will be heavy user 4G clients, because they are capable
of much higher sustained throughput when uploading or downloading large
(multimedia, video or zip) files. Multiple concurrent PC users will likely
stress test a 4G network's performance guarantees. In particular, 4G networks
will need to provide large amounts of bandwidth to multiple simultaneous users
along with QOS for differentiated services and applications.
But what are those new services and applications? A huge problem for wireless
operators is that their revenues are not keeping pace with the great increase in
network bandwidth consumed and the need for QOS to support multimedia and "rich
media" applications. Hence, revenue producing services must be developed and
come to market quickly for operators to get a decent ROI on their investments in
next generation mobile broadband networks.
Mobile video, gaming, music streaming, smart grid sensors, location based
services/ advertising, and other applications have been hyped for years, but no
sustainable business model(s) has yet been developed for them. Eventually, the
market will determine the apps and revenue models (charging vs. advertising)
that succeed or fail.
Session Presentation Highlights:
Lars Johnsson of Beceem expressed what seemed to be a consensus view of the four
semiconductor company panelists: "Wireless is the hard part, silicon is the easy
part." The basic premise is that the algorithms needed to achieve good
performance on an OFDMA based wireless broadband link is more difficult then
designing the silicon for that same link- especially when the end point is in
motion. The broadband wireless design challenge starts with constantly changing
signal strength and it gets more difficult once the terminal starts moving. Some
of the wireless design issues Lars identified were: signal tracking (to improve
performance under all conditions), channel estimation (allows for better
decoding), high-speed mobility, hand-off (from one base station to another),
maximum likelihood receiver (improves receiver sensitivity), interference
detection, and noise cancellation.
Ambroise Popper of Sequans stated that many core silicon functional blocks, now
used in WiMAX (IEEE 802.16e-2005) can be leveraged for 4G: the OFDM
modulator/demodulator, FEC, Channel estimation, and MIMO processing. Sequans
plans to facilitate a smooth evolution to 4G for
WiMAX network operators. They plan to develop and offer converged dual-mode IC's
for backwards compatibility with Mobile WiMAX devices. Those components will
fully support the existing 802.16e and either 802.16m or LTE (dependent on
market demand). They see efficient low-power implementation and radio
performance as key differentiators between 4G and Mobile WiMAX/802.16e.
Sequans CEO Georges Karam believes WiMAX/802.16e is providing economies of scale
to network operators that plan to offer both fixed broadband wireless and mobile
services. Of course, the big semiconductor growth opportunity is in the mobile
space, since all the smart terminal devices and gadgets would contain 4G chips
and radios. Georges believes that LTE is the future, but the issue is when will
it be commercially realizable to large number of customers? He predicts that LTE
won't happen till 2012. Nonetheless, Sequans plans to sample an LTE chip set
(baseband and RF) sometime next year. It will evolve over the next three to five
years to meet network operator requirements and have backward compatibility via
dual modes.
Alex Sum of GCT presented a very pragmatic assessment of the WiMAX vs LTE
debates. He first highlighted the cellular, WiMAX, and Wireless LAN paths, which
all converge to 4G.
Alex believes that most WiMAX operators are 'green field' operators, while
legacy cellcos are generally looking to LTE. The Greenfield WiMAX carriers are
characterized by the following attributes:
- They do NOT own existing cellular networks (with a few exceptions ), but in large #s
- They provide low cost alternatives to higher cost DSL, and high cost 3G services
- They provide data speed much better than current 3G, and even 3.5G cellular
- They are serving developed, as well as under-developed countries
- They are meeting the 'market hunger' for high, uninterrupted data speed
- With mobile dual mode devices available, it levels the wireless playing field
- IEEE 802.16m, if it is released in time, will match those higher performances of LTE
Alex correctly observes that most 3G cellular operators are committed to LTE deployments. The LTE line-up includes an awesome bunch of cellco's: Verizon and Verizon Wireless, Vodafone, KDDI, DoCoMo, CMCC (China Mobile is planning TDD-LTE). Here are some of Alex's observations and expectations for LTE:
- LTE FDD development is ahead of TDD by at least six months (FDD needs two transmit/receive chains and is hence more expensive to implement than a TDD component)
- Just like UMTS and WiMAX, initial LTE device introduction will follow a maturation trend, but of course there will be some surprises
- LTE will be data-centric with PC data cards, USB dongles, and smart phones
- Femto APs will be developed and installed within homes and buildings (for better indoor penetration and to take traffic off cellular networks)
- Finally, embedded devices and handsets will become available
From GCT's perspective, WiMAX is and continues to be a very viable market. It is
a growing into a very large world market, certainly not a niche. It will pay off
handsomely for all those who have invested and persisted. The strong eco-system
being built-up by WiMAX will enable IEEE 802.16m to prove itself to be a strong
competitor for LTE. WiMAX and LTE are both OFDMA based, so they could be
complimentary offerings, and could even converge. GCT is keeping a close eye on
the industrial trend and commercial developments.
Editors Note: GCT's Mobile WiMAX Wave 2 single-chip GDM7205, which supports both
2.3GHz and 2.5GHz, has been integrated into LG Innotek's new M-WiMAX SIP module.
This module is said to be the smallest Mobile WiMAX module available today.
Raj Singh, CEO of Wavesat- an innovator in multimode 4G baseband chipsets -
touted the company's Odyssey architecture, where a single vendor programmable
chipset can be used to support WiMAX/802.16e, LTE and XGP in different versions/
part numbers. A vendor programmable Air-Interface chip architecture was said to
offer flexibility and "uncompromised" performance. The following Odyssey
attributes were highlighted:
- Programmable 4G PHY layer
- WiMAX Wave 2 (MIMO Matrix A & B, beam-forming and Hybrid-ARQ), LTE Cat 3, XG-P 1.0 (Japanese version of 4G)
- TDD & FDD with channelization of up to 20 MHz
- Adaptive modulation schemes (up to QAM-256 in DL and UL), up to 1K FFT, multi-zone support per frame and advanced FEC techniques
- Enhanced Security Protocol (EAP, AES and PKMv2)
- OTA In-field programmable
Raj suggested there were several 4G market segments, defined by category:
- Fixed Data Access: Last Mile backhaul, DSL replacement, Femotcells
- Data Mobility: Notebook, MID, UMPC, Handset
- Embedded: Security Cameras, Game consoles, Wireless HDMI, Digital cameras
- Voice: VoIP, GSM, CDMA
There might be several 4G Wireless Standards in different parts of the world,
with some countries going with WiMAX, others with LTE, or their own home grown
versions of 4G (e.g. Japan and China). [Author's Note: If there were too many 4G
variants, the worldwide 4G market could be fractured, with insufficient volumes
to drive prices down. Further, there would be serious interworking and roaming
problems for users that traveled.]
Advances in semiconductor technology were seen as an enabler of 4G network and
device capabilities. In particular:
- Very dense process geometry
- Very low power (needed for long battery life)
- Mixed signal availability on bulk CMOS
- CMOS volume drives pricing
- Dense geometries allow significant integration
4G Discussion Topics:
The consensus belief of the four participants was that WiMAX/ 802.16e is a very
credible competitor to 3G networks and it will be a commercial success - even if
true mobility doesn't happen on a large scale. The networking technology just
"won't be as sexy." While all of the companies mentioned are offering WiMAX
components, only Sequans and Wavesat stated they were also developing LTE chips/
chip sets.
During the panel session, Ambroise Popper of Sequans said it was not likely for
a semiconductor company to combine 3G and Mobile WiMAX on the same chip/ chip
set, because those two wireless networks would generally not be built out by the
same network operator. (Again, the one exception we know of is SPRINT, which has
its EVDO based 3G network and will be a MVNO for Clearwire's Mobile WiMAX
service.),
Jose P. Puthenkulam- Intel's WiMAX Standards Director and 4G visionary- recently
commented on the MVNO model and shared network approach to offering 4G services:
"I feel the model where every operator goes out and builds a nationwide wireless
network is broken. It creates an entire duplicate network infrastructure and
results in more costs being passed on to the end user. With network sharing and
MVNO models, there is more scale and also better capital efficiency and overall
end users will get more affordable services."
Jose also has a strong opinion on mobile VoIP: "I see Mobile VoIP happening on
WiMAX first even before LTE. The reason is that today 3G networks have been
designed to also support Circuit Switched (CS) voice. So as 3G voice is
primarily still going to be circuit switched, there will be a push to continue
CS voice over LTE networks to maintain seamless behavior.
One huge advantage for WiMAX is that it has no legacy (backward compatible
network) and therefore will be able to always use Mobile VoIP. That allows for
rich augmentation of voice services. However LTE networks with CS voice will be
the same old cellular voice (to be backward compatible with 2G and 3G) for some
time to come."
More from Jose in a two-part wimax.com interview, to be published in the very
near future.
References:
1. The May 13th ComSoc session presentations and speaker bios can be accessed
from:
http://www.ewh.ieee.org/r6/scv/comsoc/ComSoc_2009_Presentations.php
2. At our March 25th meeting, Intel presented a Mobile WiMAX Update and IEEE
802.16m (the 4G version of WiMAX). Presentation is at:
http://www.ewh.ieee.org/r6/scv/comsoc/Talk_032509_WiMAXUpdate.pdf
3. Are LTE and mobile WiMAX really 4G networks? A look at ITU-R IMT Advanced
Requirements
http://viodi.com/2008/12/30/itu-r-imt/
4. How will wireless network operators cope with the coming bandwidth
bottlenecks of the 'Zettabyte Era?'
http://wimaxcommunity.ning.com/profiles/blogs/how-will-wireless-network
_____
tags:
Absence of MIDs leave Mobile WiMAX hanging
I attended your ComSoc January 2008 meeting, where Rama Shukla of Intel talked about MIDs providing a much better "Internet experience" then you could get on a mobile phone or sub notebook PC. 18 months later, there are no MIDs available- atleast not in the U.S. or anywhere except possibly Korea. What happened?
Some are already available
Very good article
Peak bandwidth: WiMAX wins over 3G
Where is Intel in WiMAX chip market?
It seems incongruous that Intel can be the biggest investor, cheer leader, and flag waiver for WiMAX, but maintain such a low profile in the WiMAX chip market. It appears they are only interested in selling their AToM processor, rather than WiMAX chips/ chip sets. Why doesn't Intel respond to wimax.com articles or comments?
Where is Intel in WiMAX chip market?
Intel Capital just invested $43M in UQ Communications- a Japanese WiMAX network operator that is owned by several Japanese companies and Intel Capital. UQ has an ongoing Mobile WiMAX trial and is expected to go live with commercial service next month.
Someone from Intel will have to comment on their WiMAX chip strategy and direction.
Why did Intel cancel Rosedale 2?
Intel drops WiMax chip due to “major drop in demand”
http://www.tgdaily.com/content/view/42736/135/
Also, where are the WiMAX MIDs that Intel said would be available for purchase at retail store's by late 2008?
The future of WiMAX is disruptive
>Jose P. Puthenkulam's comments are correct: not every operator will have the spectrum bandwidth or find it an advantage to do nationwide deployments of NG-4G networks. part of Clearwire's strategy is said to be to offer capacity to 3G operators as an overlay. Mobile data networks are becoming IP based such that applications including the most compelling e.g. VoIP and video will make the transport network preference less strategic to revenues. And multiple chip sets and SoCs will allow devices to bridge networks. So long as roaming agreements between 3G, WiMAX and LTE become feasible, the network becomes less a determinant.
Operators are being driven to innovation through higher bandwidth applications and open development. This hasn't been the primary driver for fixed-nomadic WiMAX and may not be for DSL replacement and emerging markets but is the fuel for 3.5G, mobile WiMAX/802.16e, and even more so for NG WiMAXm and LTE-Advanced. Innovation in apps tied to wed portals and devices helps drive mobile subscribers... but how whether WiMAX needs to do likewise or can develop more undeterred momentum will help determine how well it does as a mobile network.
WiMAX is now a credible competitor but remains primarily a choice for greenfield operators due to revenue migration more than network migration. LTE focuses more on evolving interfaces to legacy networks and optimization for mobility but if that were the only concern then WiMAX could have easily been adopted as the core standard that could be enhanced to become LTE. There is movement to have these networks work more harmoniously such as hand-offs between networks and commercial systems and devices make much use of common areas of design, but still not core compatibility. WiMAXm/802.16m follows .16e in preferring TDD access. There will be much in common between it and the LTE-TDD flavor of LTE-Advanced that is being championed by the Chinese. Perhaps commercial adoption trends will press greater harmony to evolve, if not in core standards, then in multi-mode chips and devices and common base station platforms.
As pointed out, the coding that includes mobile hand-offs, adaptive modulation techniques, MIMO-AAS are a more difficult, longer gestation and ongoing development than the WiMAX or LTE ICs. But the chips are an enabling factor and can be critical to how or if WiMAX and LTE converge into a de facto harmony that works. That will likely be more critical in years to come for WiMAX than for LTE which can more easily ride the coat tails of incumbent network operators.
The statement, "China may have its own 4G standards as well, making for a very confused 4G world. For example, China Mobile is said to be planning for a TDD version of LTE that will be backward compatible with TD-SCDMA and GSM.", is a contrivance on the part of the Chinese government and firms including Datang. TD-SCDMA will be backward compatible via multiple mode capability which will primarily be needed only within China. WiMAXm and TDD-LTE will have much more in common than either with TD-SCDMA. This is primarily a saving of face due to failure of TD-SCDMA to gain full support within China and no momentum elsewhere. China's huge market and strong financial position provides them with all the face saving they will need to push LTE-TDD forward internally and stand a good chance to ride ride that internationally.
LTE (or WiMAX) will not displace existing networks for several years with 2012 being a fair guess of when first deployments start in earnest. But even then, the majority will be similarly greenfield rather than re-farming of 2G-3G spectrum.
The question remains how much LTE will go after greenfield deployments. Suppliers and operators of LTE may be too overbuilt in cost structure needed to support incumbent networks to effectively pursue the more open business models and low to the ground cost structure needed for emerging markets and low cost MtM service.
The real battle is and will shift to what is done with these networks, not the chips, networks themselves: in order to be a firm contender for the mobile mass markets, WiMAX must tap into and spark greater innovation of applications before the window of opportunity evaporates. Some of that innovation is simply being a flat IP network - that is disruptive in itself but has to ride relatively scarce mobile spectrum to gain market dominating volumes.
Since the 3GPP effort has become the '3G Borg' in adopting (assimilating) similar MIMO-AAS OFDMA technologies, the extent of long term success for WiMAX depends on fulfilling its role as being disruptive in forcing change earlier and more open than the incumbent industry is willing or reasonably can support.
Robert Syputa
Intel gets the MOBILITY message - or do they?
Whatever happened to “the Internet in Your Pocket” and WiMAX MIDs that Intel promised over 2 years ago? Once the devices become popular, apps will be developed, e.g. music streaming, mobile video on-demand, camera photo uploads, games, LBS, etc.
Here's an article describing some of Intel's mobility oriented research projects:
http://www.forbes.com/2009/06/18/intel-future-apple-technology-breakthoughs-moorestown.html
The latest project results will be disclosed at the IEEE ComSoc-SCV October 14th meeting by the CTO of Intel's Mobility Research Group.
Whatever happened to “the Internet in Your Pocket” and WiMAX MIDs that Intel promised over 2 years ago?
The vision remains alive and well but all the obstacles along the way have to be overcome step by (sometimes bloody) step. WiMAX has not become 'fully mobile' for two basic reasons:
1) the low power chips had to evolve to enable ore powerful wireless and processing capabilities and decently high resolution graphics.
2) These had to have somewhere to use them.. cool devices that sit on the floor of a warehouse just doesn't cut it. The nationwide deployments into low enough frequency spectrum to not be tripped up by the fundamental laws of physics had to be made. Most WiMAX deployments have been in 3.5GHz which is not mobile spectrum... signals have a hard time penetrating into buildings and traveling far enough to make deployments cost effective for mass markets. WiMAX had to work with what was available.
Clearwire has 2.5GHz spectrum that is in between being too high for mobility and too low to do real creative things in development of MIMO-AAS and micro-cell architectures. For WiMAX to become a mass market phenom, the capital, spectrum had to be gathered in order to do the deployments and, in turn, for all us lovely idiots to pick up devices and have them communicate.
The UMDs and embedded consumer devices that have been envisioned had to have a mass market to sell into to make the fine tuned development worthwhile. Understanding how this comes together takes tracking the separate spheres of development. It is coming together and you will see it more visibly over the next two years.
BTW, check out today's announced agreement between Intel and Nokia... including on HSPA and new device development.
Robert Syputa
Intel based MIDs will need Moorestown for lower power dissipation
Intel has confirmed that its next-generation Moorestown processor will utilize platform power management (PPM) technology to facilitate a 50x reduction in idle power compared to current Atom-based devices. According to Intel CTO Justin Rattner, PPM represents a "fundamentally new approach" and introduces "changes to silicon" that allows hardware to play a major role in the reduction of power consumption.
Rattner explained that Moorestown-based hardware implements policies determined by the OS to manage power "in much less time" and at much "finer granularity." For example, the system will be capable of automatically reducing power and shutting down idle components - such as wireless radios or I/O subsystems - and instantly powering back up with "zero" impact to the user.
http://www.tgdaily.com/content/view/42929/135/
Comment and Analysis:
This confirms to us that Intel based MIDs will be powered by Moorestown and not the current generation of the Atom processor. We expect 3G-HSPA MIDs from LG and Nokia to be the first one's on the market- sometime in the first half of 2010 or perhaps later.
We are not aware of any WiMAX MIDs with Intel inside and we don't expect any for the rest of this year.
Huge opportunity for Beceem, Sequans, GCT and Wavesat to stimulate and profit from the WiMAX MID market. Let's look to UQ in Japan, KT in South Korea and M-Taiwan program for leadership here.
Whatever happened to “the Internet in Your Pocket” and WiMAX MIDs that Intel promised over 2 years ago?
With the semiconductor industry moving ever more deeply into System on a Chip (SoC), Intel needs to combine broadband wireless silicon with its low power processors. Using Mobile WiMAX home grown silicon, there is no licensing cost. If they have to license LTE silicon, there would be a substantial licensing charge per SoC sold. Hence, it is critical to Intel for Mobile WiMAX to succeed.
Great article, but we need more WiMAX devices
My concern is that mobile WiMAX can not be successful without more devices, e.g. smart phones, MIDs, cameras, combo-gadgets, etc. If those devices are offered, then chip companies can attain volume production and drive costs down. Elasticity of demand will prevail resulting in more Mobile WiMAX users. But will this scenario happen? If not, WiMAX will be restricted to fixed and nomadic broadband access and become a niche market.