The possibilities with WiMAX – Ruhsan Rahman

Swooosh……..you see a car going by and inside Mr. Rizwan is busy working on his laptop sitting at the back seat. Mr. Rizwan is using the mobile WiMAX solution as provided by his provider. He’s using high speed data connectivity to send his mails; chat with friends and colleagues; make IP calls and even uses video-conferencing — all this and many more solutions are possible today due to mobile WiMAX. Yes, mobile WiMAX is now a reality!

Worldwide Interoperability for Microwave Access or WiMAX is a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to wired broadband like cable and DSL. WiMAX provides fixed, nomadic, portable and, now, mobile wireless broadband connectivity without the need for direct line-of-sight with a base station. In a typical cell radius deployment of three to ten kilometers, WiMAX Forum Certified systems can be expected to deliver capacity of up to 40 Mbps per channel, for fixed and portable access applications. WiMAX has the potential to do to broadband Internet access what cell phones have done to phone access. In the same way that many people have given up their “land lines” in favor of cell phones, WiMAX could replace cable and DSL services, providing universal Internet access just about anywhere you go. WiMAX will also be as painless as WiFi — turning your computer on will automatically connect you to the closest available WiMAX antenna. A recent conference in Singapore, the WiMAX Forum announced that the first eight Mobile WiMAX products received the WiMAX Forum Certified Seal of Approval following rigorous testing to ensure that each product meets strict interoperability and conformance to standards. The 2.3 GHz frequency band products, including four base station and four subscriber unit modules, that achieved WiMAX certification are from WiMAX Forum member companies POSDATA, Runcom Technologies Ltd, Samsung Electronics Co. Ltd and Sequans Communications. Each of the newly certified products was on display at WiMAX Forum Asia Congress 2008 in Singapore.
WiMAX is based upon the IEEE 802.16 standard enabling the delivery of wireless broadband services anytime, anywhere. WiMAX products can accommodate fixed and mobile usage models. The IEEE 802.16 standard was developed to deliver non-line-of-sight (LoS) connectivity between a subscriber station and base station with typical cell radius of three to ten kilometers. All base stations and subscriber stations claiming to be WiMAX compliant must go through a rigorous WiMAX Forum Certified testing process. WiMAX Forum Certified systems can be expected to deliver capacity of up to 40 Mbps per channel. This is enough bandwidth to simultaneously support hundreds of businesses with T-1 speed connectivity and thousands of residences with DSL speed connectivity. The WiMAX Forum expects mobile network deployments to provide up to 15 Mbps of capacity within a typical cell radius of up to three kilometers. WiMAX technology already has been incorporated in notebook computers and PDAs to deliver high speed mobile Internet services anytime, anywhere.
WiMAX will provide broadband connectivity anywhere, anytime, for any device and on any network which guarantees high speed internet access where it is currently unavailable. WiMAX substantially increase data speeds for applications to include online gaming, streaming video, video conferencing, VoIP and location based services WiMAX is suppose to drive wireless Internet equipment and access prices to a competitive price point comparable to cable, DSL, and fiber Internet services. With a robust telecommunications infrastructure already in place in the U.S. Mobile WiMAX services from Sprint and Clearwire will reach more than 150 million consumers by year end 2008. In Australia, WiMAX technology will establish an affordable and efficient broadband network. This wireless broadband technology is perfectly suited for regional and rural areas and the purchase and installation process of WiMAX technology is faster, simpler and cheaper than other offered solutions. Additionally, the non-line-of-sight (NLoS) capability means that WiMAX technology can provide coverage despite the challenges of geography and the limited footprint of wireline. Taiwan has continued its leadership in the development and deployment of WiMAX operability with six commercial WiMAX licenses awarded in July 2007 for six separate Taiwanese wireless communication providers. In regions like Taiwan, where users are spread out and the wireless traffic is going a long distance, WiMAX technology provides a reliable, inexpensive solution for constant wireless broadband connectivity. In Africa as a developing continent, WiMAX technology provides the opportunity to connect the African people with Internet and VOIP services faster and more affordably than wireline. In Aisa, there have been many success stries, of which Korea is one.
A key differentiator for WiMAX is the interoperability of WiMAX Forum Certified equipment, resulting in mass volume economy of scale and assurance for service providers that when buying equipment from more than one company, the technologies are interoperable. The WiMAX Forum has assembled an alliance of leaders in the communications and computing industries to drive a common platform for the global deployment of IP-based broadband wireless services. Other key elements include cost, coverage, capacity and standards for both fixed and mobile wireless usage models.
A standard based platform for WiMAX technology drives down costs delivering volume economics to WiMAX equipment.
The technology behind WiMAX has been optimized to provide excellent non-line-of-sight (NLoS) coverage. NLoS advantages are coverage of wider areas, better predictability of coverage and lower cost as it means fewer base stations and backhaul, simple RF planning, shorter towers and faster CPE install times. Thanks to techniques for improving NLoS coverage, such as diversity, space-time coding, and Automatic Retransmission Request (ARQ), coverage are increased.
A key advantage of WiMAX technology is to use Orthogonal Frequency-Division Multiplexing (OFDM) over Edge, GPRS, HSPA to deliver higher bandwidth efficiency and therefore higher data throughput, with more than one Mbps downstream and higher data rates. Adaptive modulation also increases link reliability for carrier-class operation and the possibility to keep higher order modulation at wider distance extend full capacity over longer distances. By leveraging the same technology networks, WiMAX technology will become the most cost-effective solution for carriers to deploy for any usage model from fixed to mobile.The WiMAX Forum certifies products for conformance and interoperability based upon the standards IEEE 802.16.
In an usual instance, where one can market WiMAX could be as following when one would happen to have WiMAX solution. An Internet service provider sets up a WiMAX base station 10 miles from one’s home. The customer would buy a WiMAX-enabled computer or upgrade one’s old computer to add WiMAX capability. The customers would receive a special encryption code that would give access to the base station. The base station would beam data from the Internet to the computer (at speeds potentially higher than today’s cable modems), for which one would pay the provider a monthly fee. The cost for this service could be much lower than current high-speed Internet-subscription fees because the provider never had to run cables.
A city-wide blanket coverage of wireless Internet access sounds great, but companies aren’t going to go around setting up WiMAX base stations out of sheer kindness. Who’s going to pay for WiMAX? Well,It depends how it will be used. There are two ways WiMAX can be implemented — as a zone for wireless connections that single users go to when they want to connect to the Internet on a laptop (the non-line-of-sight “super WiFi” implementation), or as a line-of-sight hub used to connect hundreds of customers to a steady, always-on, high-speed wireless Internet connection.
Under the “super WiFi” plan, cities might pay to have WiMAX base stations set up in key areas for business and commerce and then allow people to use them for free. They already do this with WiFi, but instead of putting in a bunch of WiFi hot spots that cover a few hundred square yards, a city could pay for one WiMAX base station and cover an entire financial district. This could provide a strong draw when city leaders try to attract businesses to their area.
Some companies might set up WiMAX transmitters and then make people pay for access. Again, this is similar to strategies used for WiFi, but a much wider area would be covered. Instead of hopping from one hot spot to another, WiMAX-enabled users could have Internet access anywhere within 30 miles of the WiMAX base station. These companies might offer unlimited access for a monthly fee or a “pay as you go” plan that charges on a per-minute or per-hour basis.
The high-speed wireless hub plan has the potential to be far more revolutionary. If you have high-speed Internet access now, it probably works something like this: The cable (or phone) company has a line that runs into your home. That line goes to a cable modem, and another line runs from the modem to your computer. If you have a home network, first it goes to a router and then on to the other computers on the network. You pay the cable company a monthly fee, which reflects in part the expense of running cable lines to every single home in the neighborhood.
The WiMAX Forum recently announced it projects more than 133 million WiMAX users globally by 2012. The forecast is based on the results of an independently commissioned research study to be published in April 2008. Additional data from the study estimates that approximately 70 percent of the forecasted WiMAX users by 2012 will utilize mobile and portable WiMAX devices to access broadband Internet services.
The report entitled, WiMAX Forum Worldwide Subscriber and User Forecasts, examines the progress of WiMAX service providers, equipment vendors, content developers and users in regions around the world. The preliminary results released at the CTIA Wireless Conference in Las Vegas reflect the accelerated growth of the WiMAX ecosystem, the acceptance of WiMAX technology and demand for mobile Internet services across the world.
“We are very pleased with the inaugural WiMAX Forum Congress Asia event,” said Ron Resnick, president and chairman of the WiMAX Forum. “We surpassed our attendance expectations, provided the WiMAX industry with a trade show that was high energy and busy on the exhibit floor for both days and facilitated extensive networking and information gathering opportunities with the experts from key vendors – all under one roof. Our conference was well received, as we tried to create an engaging and interactive program with opportunities for provocative panel discussions and audience participation, as well as details by service providers outlining their experiences and plans to deploy WiMAX.”
WiMAX can bridge the divide and connect the unconnected
In summary the following conclusions can be drawn regarding the status of the market:
o There is high global demand for broadband connectivity in regions with low population density in both developed and developing countries
o The best solution to bridge this divide is a cost-effective, globally standardized wireless technology
o A technology such as WiMAX can cost-effectively serve fixed, nomadic, portable, and mobile usage models for broadband services on a global scale.
Mobile WiMAX
o WiMAX is also called Mobile WiMAX as it can serve all usage models from fixed to mobile with the same infrastructure. Based on the IEEE 802.16e-2005 standard, Mobile WiMAX offers fixed, nomadic, portable and mobile capabilities
o Does not rely on line-of-sight transmissions in lower frequency bands (2 to 11 GHz)
o Provides enhanced performance, even in fixed and nomadic environments
o Currently uses Time Division Duplexing (TDD)
o System bandwidth is scalable to adapt to capacity and coverage needs

Fixed WiMAX:
The deployment of Fixed WiMAX™ networks to address “last mile” broadband access has been highly successful in the last few years, and that model is reasonably well understood. However, the deployment of Mobile WiMAX by existing mobile operators has highlighted some important questions, the answers to which this paper provides high level direction.
OFDM & MIMO: Technologies of Choice for Mobile Broadband
2.5 and 3G networks have enabled users around the world to access data on their handsets and laptops. However, as mobile data services increase and more PC users start using the same broadband Internet applications “on the go” as they do at home, the expectation is for mobile data traffic to grow by a factor of 10x between 2010 and 2015.1 And this requirement could easily exceed expectations with a surge in applications like rich social networking which combine Internet multimedia and mobility. Although 2.5 and 3G networks will continue to serve up voice and mobile data for the foreseeable future, these networks will become capacity constrained as mobile broadband data use increases. Hence, the deployment of new networks to offload data-intensive mobile broadband applications is inevitable. Along with increased and scalable data capacity, these new networks will be capable of supporting new, open Internet models and new device distribution and subsidy models — flexibly accommodating operators’ business model needs.
OFDM & MIMO have emerged as the technologies of choice to satisfy this growth, not only for WiMAX, but also for 3GPP’s future LTE2 standard as well as Wi-Fi (802.11n). The combination of OFDM and MIMO is highly scalable and systems based upon it are best positioned to satisfy the headroom requirements for mobile broadband data over the next decade.
In 2007, commercial Mobile WiMAX Release 1.0 systems which have not yet incorporated MIMO capability, showed a consistent 3x capacity improvement over other mobile wireless solutions in the same amount of spectrum. And that’s just the start. In 2008, MIMO-enabled WiMAX systems are expected to deliver 50% gains over the current SISO implementations. In 2010, wider channel bandwidth support in Release 1.5 will enable peak data rates well in excess of 100 Mbps using 20 MHz channels. In the future, when equipment can cost effectively support 4×4 MIMO configurations, peak data rates of over 300 Mbps will be achievable.
The Migration Path to 4G (OFDMA-MIMO)
The 3G evolution from WCDMA to HSPA or equivalently, CDMA2000 to EV-DO — all technologies based upon CDMA — was achieved via upgrades to operators’ existing 3G networks utilizing the same spectrum. These upgrades will continue, but fundamentally these networks do not have the scaling capability to address future data traffic patterns associated with mobile broadband use. (Higher order MIMO antenna configurations are the core enabler for scaling throughput of OFDM/MIMO systems over the next decade, but CDMA support for higher order MIMO is not efficient. For this reason, IEEE 802.16, 3GPP and 3GPP2 standards bodies are all adopting OFDM & MIMO for 4G.) Since there is no expectation to decommission operational 2G & 3G networks, new OFDMA-MIMO data overlay networks — be they WiMAX today or, in the future, LTE — must be deployed in new spectrum, preferably spectrum offering wider swaths of spectrum to enable very high data capacity.
The addition of an OFDMA-MIMO mobile broadband data overlay network involves deployment of new base station line cards and clients as well as upgrades to the core network to support high amounts of IP (Internet Protocol) traffic. That said, existing mobile operators can co-locate WiMAX base station equipment in their existing 2G or 3G cell sites. In mobile WiMAX commercial deployments to date, we have seen a cell site re-use rate of 70%.
Migration Path to 4G (OFDMA-MIMO)
The 3G evolution from WCDMA to HSPA or equivalently, CDMA2000 to EV-DO — all technologies based upon CDMA — was achieved via upgrades to operators’ existing 3G networks utilizing the same spectrum. These upgrades will continue, but fundamentally these networks do not have the scaling capability to address future data traffic patterns associated with mobile broadband use. (Higher order MIMO antenna configurations are the core enabler for scaling throughput of OFDM/MIMO systems over the next decade, but CDMA support for higher order MIMO is not efficient. For this reason, IEEE 802.16, 3GPP and 3GPP2 standards bodies are all adopting OFDM & MIMO for 4G.) Since there is no expectation to decommission operational 2G & 3G networks, new OFDMA-MIMO data overlay networks — be they WiMAX today or, in the future, LTE — must be deployed in new spectrum, preferably spectrum offering wider swaths of spectrum to enable very high data capacity.
The addition of an OFDMA-MIMO mobile broadband data overlay network involves deployment of new base station line cards and clients as well as upgrades to the core network to support high amounts of IP (Internet Protocol) traffic. That said, existing mobile operators can co-locate WiMAX base station equipment in their existing 2G or 3G cell sites. In mobile WiMAX commercial deployments to date, we have seen a cell site re-use rate of 70%.
WiMAX bands:
The WiMAX Forum operates in 2.3 – 2.7, 3.4- 6 and 5.8 GHz bands. The WiMAX Forum is working with operators and equipment manufacturers to expand the frequency allocation to cover all the key spectrum bands that our member companies identify as interesting to potential WiMAX service providers such as 700 MHz. For mobile applications, initial profiles have been developed for 2.3, 2.5, and 3.5 GHz. These are to address the current market demands. The WiMAX Forum has the ability to respond rapidly to development of additional profiles as additional spectrum is auctioned or markets change.
The WiMAX Forum:
The WiMAX Forum was established in June 2001 and is an industry-led, not-for-profit organization of more than 520 companies to include over 200 operators formed to certify and promote broadband wireless products based upon the harmonized IEEE 802.16/ETSI HiperMAN standard. The WiMAX Forum strives to ensure global adoption of a common platform to deliver Broadband Wireless services as a standard alone is not enough to effect mass adoption of a technology. Along these lines, the Forum works closely with service providers, regulators, equipment manufacturers, test equipment manufacturers, Certification labs, and application service providers to ensure that WiMAX Forum Certified systems meet customer and government requirements. WiMAX Forum Certified™ products are fully interoperable and support all usage models of broadband wireless services.
Vision: Global adoption of WiMAX as the Internet technology of choice anytime, anywhere. Mission: We are a global forum for the communications industry, recognized for certifying WiMAX products, publishing technical specifications, aligning member interests, and influencing the ecosystem to accelerate and promote deployment of WiMAX services and infrastructure.
Members: Currently, the WiMAX Forum® has over 520 member companies, including leading equipment manufacturers, service providers and systems integrators. A complete list of members is available online at http://www.wimaxforum.org/about/ Officers and Board of Directors: The Board of the WiMAX Forum is comprised of industry leaders within the broadband wireless ecosystem. Board members are committed to provide guidance and direction to the Forum to ensure the WiMAX Forum organizational staff executes on its vision and charter.
President and Chair: Ron Resnick,
Intel Vice President: Dr. Mohammad Shakouri, Alvarion
Board of Directors: Ray Abrishami, Fujitsu
Rajesh Bhalla, ZTE
Chris Cheeseman, BT Group plc
Manish Gupta, Aperto Networks
Dr. Hyun-Pyo Kim, KT
Christophe Lerouge, Alcatel-Lucent
Scott F. Migaldi, Motorola
Dr. Hideo Okinaka, KDDI
Joonho Park, Ph.D., Samsung
Dean Prochaska, Sprint
Paul Senior, Airspan Networks
Dr. N. K. Shankaranarayanan,
AT&T Jari Vainikka, Nokia
Additional Officers: Secretary: David Sumi, TeleCIS Wireless
Assistant Secretary: Bruce Holloway, WiMAX Forum
Chief Financial Officer: Batya Marks, WiMAX Forum
As discussed with Dr. Shakouri during the seminar, he expressed strong support for WiMAX, as he believes, this technology will change the telecommunication and data connectivity and bring a new stream of revolution. He also feels that other competing technologies like LTE (Long Term Evolution) and UMB (Ultra Mobile Broadband) will not have such a high growth potential in terms of last mile connectivity. Same can also be envisioned of HSPA. So, the Forum is bracing itself for a three horse race between GSM, CDMA and WiMAX. Hence, let us prepare ourselves for the ‘true’ high speed tomorrow as Mobile WiMAX is here to stay!

Ruhsan Rahman is a telecom analys