Tuesday, 21 August 2007

Prepare for WiMAX 2.0



I was completely unaware of IEEE 802.16m which is promising speeds upto 1Gbps. Only when someone asked me what my opinion was on this i did some digging in this.


IEEE 802.16m promises to deliver speeds up to 1Gbps and be backward compatible with 802.16e-2005 (mobile WiMAX) solutions. The 802.16m group should wrap up the technology development phase in 2007. Similar to existing mobile WiMAX, 802.16m will use multiple-input/multiple-output (MIMO) antenna technology. The idea with 802.16m, though, is to increase bandwidth by using larger MIMO antenna arrays.


The 802.1m group is targeting ratification and finalization of the standard by late 2009. So, we’re still a couple of years (or more) from having a gigabit version of WiMAX. As compared to other IEEE 802 standards development, such as 802.11, this is an aggressive schedule. In my opinion, these will be difficult dates to hit, especially with the requirement for being backward compatible with 802.16e-2005.


The advantage of 802.11m to cellular companies is that it could allow the convergence of 3G and 802.16 into a single 4G technology for mobile and fixed applications. This would enable cellular companies to offer service, such as IPTV and VoIP, as effectively over wireless connections as they are today on wired networks. This would lead to competition with existing fixed wireless broadband services currently delivered over cable and telephone lines.


Many vendor sources however, have expressed some skepticism about the speed with the work can be completed (the end of 2009 is being mooted as a baked date) and the chances of maintaining backwards compatibility with mobile 802.16 technology. Some folks worry that carriers have unrealistic expectations on how fast new WiMax profiles and interfaces can be developed. "They just walk in, snap their fingers, and expect it to happen," one industry source told us on the show floor yesterday. After all, it took several years for the IEEE to arrive at a satisfactory fixed broadband wireless specification in the form of 802.16d and even longer for the WiMAX Forum to certify interoperability between products using the technology.


Martin has some interesting analysis on his Mobile technology page:


Between today and WiMAX II, there's systems such as WiMAX and LTE which promise faster data rates than those available today by mainly doing the following:
  • Increase the channel bandwidth: HSDPA uses a 5 MHz channel today. WiMAX and LTE have flexible channel bandwidths from 1.25 to 20 MHz (Note: The fastest WiMAX profile currently only uses a 10 MHz channel today for the simple reason that 20 MHz of spectrum is hard to come by). So by using a channel that is four times as broad as today, data rates can be increased four times.
  • Multiple Input, Multiple Output (MIMO): Here, multiple antennas at both the transmitting and receiving end are used to send independent data streams over each antenna. This is possible as signals bounce of buildings, trees and other obstacles and thus form independent data paths. Both LTE and WiMAX currently foresee 2 transmitting and 2 receiving antennas (2x2 Mimo). In the best case this doubles data rates.
  • Higher Order Modulation: While HSDPA uses 16QAM modulation that packs 4 bits into a single transmission step, WiMAX and LTE will use 64QAM modulation under ideal transmission conditions which packs 6 bits into a single transmission step.
By using the techniques above, LTE and WIMAX will be able to increase today's 2 MBit/s to about 20-25 MBit/s. That's still far away from the envisaged 1.000 GBit/s. To see how to get there let's take a look at what NTT DoCoMo is doing in their research labs, as they have already achieved 5 GBit/s on the air interface and have been a bit more open at what they are doing (see

here and especially here):
  • Again increase of the channel bandwidth: They use a 100 MHz channel for their system. That's 4 times wider than the biggest channel bandwidth foreseen for LTE and 20 times wider than used for today's HSDPA. Note that in practice it might be quite difficult to find such large channels in the already congested radio bands.
  • 12x12 MIMO: Instead of 2 transmit and receive antennas, DoCoMo uses 12 for their experiments. Current designers of mobile devices already have a lot of trouble finding space for 2 antennas so a 12x12 system should be a bit tricky to put into small devices.
  • A new modulation scheme: VSF spread OFDM. This one's a bit mind bogelling using CDMA and OFDM in combination. Wikipedia contains a description of something called VSF-OFCDM which might be a close brother.


More Information available at IEEE 802.16 Task Group m (TGm) page.

Saturday, 18 August 2007

GSM/UMTS Growing faster than other technologies



A total of 564.6 million new subscriptions to GSM/UMTS services worldwide in the twelve months ending in June, with almost 18% of these from the Western Hemisphere alone, according to the estimates of Informa's World Cellular Information Service. GSM/UMTS added nearly 100 million subscriptions in the Americas during this time period, more new subscriptions than any other technology. GSM/UMTS continues to lead the wireless market of Latin America and the Caribbean, where nearly 22 million GSM users were added in 2Q 2007, increasing GSM market share in the region to 74%.

GSM is not only the leading industry standard for reliable wireless voice communication with more than 2.5 billion customers, but also plays an integral role in 3G as more than two thirds of the estimated 200 million 3G users across the globe use UMTS/HSPA technology for mobile broadband. There are currently 181 UMTS operators in service across 77 countries, with an additional 72 networks planned, in deployment, or in trial. Of those 181 operators, 135 have enhanced service with HSDPA, with 80 additional HSDPA networks planned. Five operators across the world have launched HSUPA technology to date, and over 130 more operators plan to upgrade with HSUPA, many in the second half of 2007.

GSM technologies account for 85% of mobile wireless customers globally. More than half a billion new subscriptions to the GSM family in the past twelve months ending June 2007 represent a worldwide growth rate of 29.5%. Focusing on the Western Hemisphere, GSM holds nearly a 60% share of market, with a subscriber base of 358 million GSM/UMTS customers, compared to 191 million for CDMA. In Latin America and the Caribbean, there are 340 million total wireless users, and of these, 253 million use GSM, which now holds a market share of 74% in the region, up from 62% one year ago.

Erasmo Rojas, Director of Latin America and the Caribbean for 3G Americas stated, “The growth in the uptake of GSM/EDGE/UMTS technologies in Latin America continues to progress. Wireless service providers are achieving great results in increased contribution to their Average Revenue Per User (ARPU) from wireless data services through their deployment of EDGE and now recently UMTS/HSDPA.” He continued, “As of June 2007, typical operator ARPU from wireless data value-added services represents more than 15% of total wireless revenue in countries such as Mexico (15%), Ecuador (20%), Argentina (24%) and Venezuela (24%).”

To view the latest statistics on wireless growth, visit the 3G Americas website at: http://www.3gamericas.org/English/Statistics/.

Friday, 17 August 2007

'3' starts MBMS trials


The mobile operator '3' has again taken a major step forward by starting Mobile-TV trials using Multimedia Broadcast Multicast Service (MBMS). The trials are in conjunction with Ericsson. The following from the press release:
3 Italy uses DVB-H for its Mobile TV offering. However, MBMS is being developed under the auspices of the global 3GPP standards body.

MBMS uses existing 3G networks and spectrum for content delivery, building on existing infrastructure. To deliver MBMS, upgrades are made to the existing network as well as content and broadcast servers. 3G mobile phones with support for MBMS are expected to be available in 2008, said the company.

MBMS is a different approach to Mobile TV combining both broadcast and unicast shows (though multicast is more accurate). It also gives consumers opportunity to interact by voting, sending messages, accessing downloads of related content and special promotions from advertisers.

"MBMS as part of the 3G evolution is an attractive technology not only because of its flexibility and efficiency, but because it's quick and easy to deploy and leverages existing infrastructure," said Kursten Leins, Strategic Marketing Manager - Multimedia, Ericsson. "MBMS allows an unlimited number of users to watch the same mobile TV program at the same time in the same area, as well as enabling valuable user interaction with advertisements, campaigns and programs."

"3 pioneered 3G in Australia, so it was a great opportunity to see the country's first MBMS technology trial run on Australia's first 3G network," Leins added. Since the MBMS signal can be pin pointed to specific geographies, it's also possible to broadcast different mobile TV programs to different areas, giving a locally-specific customer experience and also providing highly targeted mobile advertising opportunities.
"We are very happy with the trial - the technology worked well and apart from delivering a good customer experience, it's extremely efficient in terms of network traffic and capacity, and provides new levels of customer involvement with their programs," said Michael Young, Director Technology & Services, 3 Australia.
The technical trial was held in 3's Sydney Head office over 6 weeks and run by Ericsson who developed the trial system. Using four specially designed prototype handsets, Ericsson also installed equipment to simulate the content and broadcast servers on a section of 3's network so the customer and network experience could be seen.

"The trial has been very interesting, and we'll continue to work with Ericsson to keep a close eye on the technology and the handsets to support MBMS as they develop," Young added.
More on MBMS can be found here.

Thursday, 16 August 2007

FMC: Fixed Mobile Convergence


FMC will enable single device to perform myriad functions. The main points of interest are:

Dynamic increase of IP based services especially driven by fixed access
VoIP replaces circuit switched service in fixed networks
VoIP will replace circuit switched voice in mobile networks
The border between fixed and mobile networks dissapears

Source: LTE from a handset perspective, LG Electronics, 'LTE 2007', May 2007

Monday, 13 August 2007

Beginning of the Cablefree world


With UWB becoming popular and more devices about to be rolled out, the cable connections between TV, VCR, DVD players, Camcorders, etc can be a thing of past.

In UK, OFCOM removed the restrictions for the use of UWB devices upto a range of 30 metres. In the US and Japan, UWB home hubs are a popular way of sharing domestic broadband.

Ultra-Wideband (UWB) can be used to send huge amounts of information between electronic devices, making it suitable for connecting items such as digital TV decoders and DVD players to television sets, or digital cameras to computers.

It could also be used to wirelessly link satellite dishes or cable TV connections to set-top boxes, doing away with the need for cables to be poked through walls and run around skirting boards. Satellite broadcaster Sky, for instance, is understood to be looking at whether UWB could be integrated into its equipment.

Described by techies as "Bluetooth on steroids", UWB can operate over distances of up to 30 metres. Japanese electronics manufacturers are already producing modems that use UWB, while Cambridge-based chip maker ARM Holdings has deals with several companies that plan to make UWB devices.

Separately, Vodafone yesterday joined the Wimax Forum which is creating standards and specifications for a new longer-range wireless broadband technology. The company stressed that it is taking a neutral stance on the next generation of wireless technologies, but the move raised eyebrows in the mobile phone industry.

Wimax, which can operate over many miles, is seen as a competitor to another next generation wireless technology, which is being developed by the mobile phone companies and builds on the existing 3G standard. LTE, or Long Term Evolution, is an mobile industry-led project designed to upgrade the existing 3G service. The LTE group is supposed to come up with recommendations on a new standard next month.

Earlier this year Vodafone's chief executive Arun Sarin warned that the process of getting a new wireless standard was taking too long. "As an industry it takes us a long time to get things done - we need to move faster or others will eat our lunch," he said.

Meanwhile The European Commission is opening up the wireless technology market by discarding out-dated rules limiting the areas of available radio spectrum. Next-generation wireless technologies such as BlackBerrys and smartphones work best over low frequencies that, until now, were reserved for GSM mobile phones. According to a statement last week, the Commission will allow new services to co-exist alongside GSM. The aim is to establish a more flexible, market-driven approach to spectrum management, says European Union telecoms commissioner Viviane Reding.

Sunday, 12 August 2007

Training on Latest 3G/4G Topics


As i have mentioned in my posts before, i provide training on behalf of eXplanoTech. Some of the latest training available are:
Introduction to 3G/UMTS - 1-5 days
High Speed Downlink Packet Access (HSDPA) - 1 day
High Speed Uplink Packet Access (HSUPA) - 1 day
High Speed Packet Access (HSPA/HSPA+) - 2 days
Introduction to MBMS - ½ day
MBMS and Mobile TV - 1 day
Advanced MBMS - 1-2 day(s)
IP Multimedia Subsystem (IMS) - 2 days
Robust Header Compression (RoHC) - ½ day
Long Term Evolution (LTE) - 1 day
TCP/IP Refresher Course - 1 day
TCP/IP Overview for Telecom Engineers - 2 days
WiMAX and 4G Wireless - 1 day
New Wireless PAN (WPAN) Standards - 1 day
If any of these trainings interest you or your company the please drop me an email.
We also offer one to one training to executives and top decision makers. We can also offer personal one to one training to professionals looking to enhance their skills and yes we offer free seminars to interested universities. For anything that interests you, do drop me an email.

Thursday, 9 August 2007

Vodafone plays the WiMAX card

Vodafone announced that it is to become a member of the WiMAX Forum, the organisation which tests and certifies interoperability for products based on the WiMAX standards. Vodafone sees the move as a means of taking a more technology-neutral approach to the future development of its business, by placing WiMAX on a strategic par with 3G LTE for a potential role in the next generation of mobile technology. Although mobile WiMAX is less mature than LTE at present, Vodafone believes it may have an important role to play for some of its national operating companies. Vodafone therefore wants to understand WiMAX better, and to play an active role in developing end-to-end specifications for possible future deployment.

WiMAX standard is often compared to Wi-Fi, though the comparison is unfair as WiMAX isn't based on a 20-year-old wired standard but was designed for wireless use (at least, the bits not borrowed from DOCSIS were). WiMAX offers greater speed and range than Wi-Fi, but most importantly it offers quality of service guarantees that make VoIP and streaming applications easier to manage.

"Our membership of the WiMAX Forum will complement our existing memberships of other key industry bodies such as the GSMA, 3GPP, and the Next Generation Mobile Network initiative," Vodafone global chief technology officer Steve Pusey said.

WiMAX has been heavily pushed by Intel, which intends to build it into laptop chipsets, encouraging rapid adoption of a technology in which it owns key intellectual property.

According to Ovum analysis:

Although a slightly crude generalisation, it's basically accurate to see the WiMAX Forum as the wireless Internet camp; the 3GPP as the wireless telecoms camp. There was a time when those two camps represented philosophies which were mutually exclusive and frequently antagonistic. These days, it makes less sense to see the world in those terms, because convergence between telecoms and the Internet - though far from complete - is now well under way. But at this early phase of the transition to convergence, it's not yet clear whether the predominant technologies and business models will eventually be those of telecoms, or those of the Internet. It's sensible, therefore, to remain interested in (and influential over) both possible outcomes, so long as they both remain possible.

Seen in that context, it seems perfectly natural that a large mobile operator would decide to join the WiMAX Forum. In Vodafone's case, the move is especially logical because of its increasing presence in emerging markets. The prospects for WiMAX to play an important role in the future development of mobile are better in those parts of the world where large numbers of people do not yet have access to telecoms or the Internet. If alternative models are going to take root, it's most likely to happen in areas with less legacy. On the other hand, the telecoms model will predominate for the forseeable future in more mature markets. Vodafone clearly needs to be involved in the development of both types of model, since its business encompasses both types of market.

It says something about the way mobile has changed since the turn of the century, that joining the WiMAX Forum just seems like an obviously sensible thing for Vodafone
to do.

Tuesday, 7 August 2007

Which Mobile TV technology to go for?

There is aa lot of confusion regarding which mobile TV technology to go for. An article in Telecoms Online gives an idea regarding which way the Chinese market is going for mobile TV.



A recent survey shows more than 40 percent of cell phone users in China like the idea of watching TV on handsets. Some pundits even predict the number of mobile TV users in China will jump to nearly 60 million in 2008, and revenue from handset sales and programming will generate 1.3 billion yuan (US$170m).

The road to mobile TV, however, most likely will be bumpy. Current trials have found several vulnerabilities, such as handset display hang-up when video content is loaded, short battery life and overheating, that must be fixed.

What’s really hindering mobile TV development in China (and, arguably, in other geographical regions), however, is lack of agreement on one standard. In June, a government agency overseeing the mobile TV industry reaffirmed CMMB (China Mobile Multimedia Broadcasting) as the official standard for 3G video service. The reason: CMMB is homegrown and completely free of foreign IPRs.

The State Administration of Radio, Film and TV developed CMMB last October, but a tug-of-war over the standard has undermined SARFT’s efforts to implement it this year. Despite a slow start, SARFT has obtained 25MHz in bandwidth on 2.5GHz for CMMB service and plans to build networks for the Olympics in six cities, including Beijing, Shanghai and Qingdao.

The other contenders CMMB must fight are DVB-H (Europe), Media-FLO (United States), T-DMB (Korea), DMB-TH (a digital TV spec modified for handheld developed by Tsinghua University), T-MMB (Nufrontsoft, which is aligned with MII, the Chinese telecom regulatory body) and CMB (Huawei).

For now, CMMB appears to be most appealing because of SARFT backing. SARFT’s control of programming and distribution in China gives CMMB a huge regulatory and cost advantage over rival mobile TV standards.
Recognizing that CMMB has clout in China, a large industry alliance of 120 companies backs the standard, including heavyweights such as Nokia, Motorola and Sony Ericsson, and Chinese firms like Lenovo, Huawei and ZTE.


One of the main benefits of CMMB, according to SARFT, is that it does not charge royalties for two years, saving an estimated 1 billion yuan (US$130m) in foreign IPR payments. SARFT hopes the savings will encourage handset manufacturers to cooperate in perfecting the standard and expediting proliferation.

There are other concerns. Some Chinese standards are not really independent but a hodgepodge of foreign versions. Reports say T-MMB, developed by Nufrontsoft, incorporates certain core DAB patents like DMB that will be in effect until 2013. Critics say if Chinese handset makers adopt T-MMB they will have to dole out hefty royalties–about US$6 per set or up to US$120m to US$300m per year.

CMMB and T-MMB use different approaches to video transmission and delivery. T-MMB uses a streaming overlay on top of mobile infrastructure, so that it shares the total bandwidth and download speed for the service, like the current video service. CMMB relies on a tuner installed in the handset to receive video signals over the air.

The T-MMB advocates say adding a tuner will compromise other features affecting handset and overall performance, while the CMMB supporters predict T-MMB will be dead on arrival because video traffic will crash the network and cost will skyrocket.

The debate over mobile TV standards is not just about patriotism and technology. SARFT has jurisdiction over broadcasting via various media outlets, including handheld devices, while T-MMB is a brainchild of MII which, by default, only provides a transmission conduit to end users but not content and distribution.

The problem is that both sides see mobile TV as a golden opportunity but want to run the market on their own terms. At this time, the central government sees it as a market issue and is reluctant to provide guidelines, so tussle over mobile TV probably will go on for some time before technical issues are straightened out.

Monday, 6 August 2007

UMA is not Dead


I did not hear about UMA for long time and i was starting to think that this would be one of the dead technologies that never saw the light of the day. I was wrong. It was pointed out to me by a colleague that T-Mobile (U.S.) recently announced Hotspot @ home that will allow UMA access to the Mobile while within a WiFi coverage area.
Note: UMA or Unlicensed Mobile Access is no longer called UMA but by its new name GAN or Generic Access Network
T-Mobiles GAN service lets users make phone calls over their in-home WiFi networks or over T-Mobile's national cellular network, depending on whether the customer is inside a T-Mobile HotSpot or not. The big problem with UMA, though, is that users must use dual-mode phones. T-Mobile's HotSpot@Home plan currently costs $10 a month after the purchase of a dual-mode phone and WiFi router, if one isn't owned already.
AT&T (again U.S) is also planning a similar move but its going the FemtoCell Way. Industry sources have revealed that AT&T has filed a request for proposal (RFP) to suppliers that may be interested in participating in AT&T's in-home femtocell service, according to wireless trade publication Unstrung. Femtocells are access points that act as repeaters to strengthen cellular communication signals inside homes, offices, and underground areas like subways. T-Mobile is trying to accomplish a similar task with its HotSpot@Home service, which brings better call quality to subscribers through the use of WiFi routers.
Although AT&T's femtocells would likely require a broadband internet connection, femtocells don't use the WiFi routers that most people already have in their homes. Instead, users would need to buy a new plug-and-play unit that could cost in the area of $200. Companies like picoChip currently develop reference designs for units that could be used by AT&T or its suppliers.

Because femtocells do not use WiFi signals, they don't require dual-mode handsets, which opens up the market to customers that don't want to ditch their current phones just to get the benefits of a stronger in-home signal. Meanwhile, potential T-mobile HotSpot@Home customers can only choose between two phones (the Nokia 6086 and Samsung T409), which means existing customers have to ditch their current mobile phones for a dual-mode device. Blackberry 8820 will soon be available in U.S. which has support of UMA.
Meanwhile Kineto Wireless, the innovator and pioneer of UMA, recently joined femtoforum. In addition to the promotion of femtocell deployment, the forum is focused on addressing several key technical issues, including radio planning and control, provisioning and management, and device-to-core network connectivity. As the core network technology behind a growing number of large-scale, dual-mode handset deployments, the 3GPP UMA standard is now being recognized as the de-facto standard for device-to-core network connectivity in the femtocell market as well. Recently, Kineto initiated interoperability testing between femtocell access points and its industry leading UMA Network Controller (UNC), and has already completed testing with Ubiquisys, the number one femtocell access point vendor.
"The femtocell industry is starting to appreciate the three year head start
UMA has over proprietary approaches being proposed for device-to-core network connectivity," said Patrick Tao, Kineto's vice president of technology. "As the
technology behind successful l dual-mode handset services, such as unik from
FT/Orange and T-Mobile's Hotspot @Home, the 3GPP UMA standard has already identified and addressed the real-world deployment issues operators face in
bringing femtocells to market. These issues include security, device
authentication, access controls, handover, regulatory compliance, as well as
scalability to support millions of endpoints."
One thing to remember here is that not all mobiles supporting WiFi will support UMA. On the other hand all phones that support UMA will support WiFi.
An Introduction on UMA can be found here or here.

Friday, 3 August 2007

Certified Wireless USB is finally here



Two manufacturers of laptop PCs and two designers of wireless hubs and adapters are the first companies to receive consumer product certifications from the Universal Serial Bus Implementers Forum (USB-IF). The Certified Wireless USB products are expected to be in stores for the back-to-school and holiday gift season.

Previously certified silicon from Alereon, Intel Corp., NEC Corp., Realtek Corp., and WiQuest Communications are integrated into the products, according to the USB-IF.


The two laptop companies are Dell Computer for its Inspiron 1720 notebook and Lenovo for its ThinkPad T61/T61p 15.4-inch Widescreen Notebook. Networking companies D-Link and IOGear each had a wireless hub and also an adapter certified. Certification of the Wireless USB protocol by the USB-IF assures the interoperability of devices from a variety of manufacturers.

Certified Wireless USB is based on the WiMedia Alliance's Ultra-WideBand (UWB) common radio platform, which is capable of PHY-layer data rates of 480 Mbit/s at distances up to 3 meters and 110 Mbit/s at up to 10 meters.

From an engineering perspective, the question of co-existence with other wireless technologies in the 3 GHz band has been a persistent question for Wireless USB.


Dell and Lenovo have announced the first notebooks with embedded Certified Wireless USB chips - the Dell Inspiron 1720 and Lenovo ThinkPad T61and T62p. The laptops connect wirelessly to USB peripherals hooked up to Certified Wireless USB hubs such as those released by D-Link and IOGear. They will carry a Certified Wireless USB logo. In the interim, until peripherals catch up with the technology, they will need to be plugged into a wireless USB hub. This will allow the Dell and Lenovo laptops to communicate with a peripheral device such as a conventional printer plugged into the hub.