The Future of WiMAX

What do a poor farmer in a remote village in Africa and a rich business man from Manhattan have in common? Both will benefit from the coming revolution of WiMAX, the fourth generation of wireless technology. The farmer will be able to speak on a cheap cell phone for a price he can afford—a few dollars per month—even at a distance of many kilometers from his village, due to the increased coverage and low-cost services WiMAX can offer. The rich business man will be able to use continuous, pervasive, high-speed mobile internet service from his notebook PC in his office, on the way to a cafe, or in the subway. This article will cover the history, technology, (present and future) of the communication technology that will shortly change everyone’s daily lives, wherever they live.

Introduction

Wimax Forum logo
Wimax Forum logo
Worldwide Interoperability for Microwave Access, or WiMAX for short, is a next generation open standard that seeks to serve users’ increasing demands for high data throughput (broadband) services such as streaming media on the internet, live video conferencing, and mobile TV on computers as well as handsets and PDAs. WiMAX is expected to be integrated into the next generation mass market consumer devices and to offer something that does not exist today – speeds similar to cable and metropolitan area coverage while on the move, all for a much lower cost than we are used to today. WiMAX already offers broadband services in many emerging and rural markets which are not supported by wireline-based technologies and started its first deployment in developed countries replacing both commonly used Wi-Fi on one hand and traditional cellular standards such as 3G (third generation, based on “The Third Generation Partnership Project“) on the other hand. In this article, we shall try to explain the technology behind WiMAX, which includes several features resembling existing wireless technologies as well as some revolutionary new features which will bring new and improved abilities to end-users. This article will also examine the current WiMAX status and will try to evaluate the future of the technology as it competes with other standards.

 

Background

HTC MAX 4G - mobile
HTC MAX 4G – mobile “smartphone”
with a Wimax for the Russian market

Historically, the main usage of wireless data-transfer was voice communication. As wireless communication standards evolved to become digital (Wi-Fi or GSM), voice has become one among several more bandwidth consuming (broadband) applications such as high definition video or games. Many wireless IP (internet protocol) network standards try to satisfy the increasing demand for more bandwidth in more locations while on the move.

Wi-Fi is the most popular and successful broadband wireless IP network standard to date. Popular Wi-Fi standards – like 802.11b and 802.11g – are used in many homes and businesses and enable internet access with high data throughput for computer notebooks, PCs, and more recently, for Smartphone users. 802.11n, the upcoming Wi-Fi standard, (currently in draft state) can double the data throughput of Wi-Fi for heavy demanding applications. A number of cities around the world are in the process of building city-wide Wi-Fi networks to allow citizens to enjoy wireless data transfer across the city (also known as a metropolitan area network). While Wi-Fi operates over a free unlicensed spectrum and is simple to install and operate, it has some major disadvantages. One of the main drawbacks is poor signal coverage; only 30 meters indoors and 200 meters outdoors. Wi-Fi as a fixed broadband standard cannot support broadband services while on the move and does not support continuous connectivity between Wi-Fi hotspots which could enable, for instance, a person going from his office to a cafe while having a continuous wireless conversation (this shortcoming is being partially addressed, however, by the new 802.11r standard). In addition, Wi-Fi is exposed to other interferers on the same band since it runs over an unlicensed spectrum, is considered relatively insecure since it does not use enhanced encryption, is very power inefficient, and does not guarantee quality of service (the ability to guarantee a certain level of bandwidth to a subscriber, according to the service he uses).

 

 Intel's WiMAX/WiFi Link 5350 chipset (Credit Intel)
Intel’s WiMAX/WiFi Link
5350 chipset (Credit Intel)

Existing cellular networks like 3G or the more advanced 3.5G (based on high speed packet access, or HSPA, a family of standards that extend and improve the performance of existing 3G) can only partially satisfy broadband wireless demands. Cellular networks are continuously connected everywhere, where one base station can cover a small medium sized neighborhood at a range of more than 3 kilometers, but the bandwidth of existing cellular standards is relatively small (up to 3.1Mbps for 3G, compared to Wi-Fi, which can support bandwidth effectively up to 30Mbps in 802.11g), and even more expensive compared to Wi-Fi due to the need for the deployment of expensive cellular base stations and the expensive spectrum of service providers versus the cheap and easy Wi-Fi hotspot deployment and free unlicensed Wi-Fi spectrum.

Hybrids consisting of cellular networks and Wi-Fi technology are a new approach that is intended to enable the transition from cellular networks to Wi-Fi and back to the same or different cellular networks within range. Before this technology will be ready for commercial use, it must solve the issue of continuous automatic service between the cellular network provider and the broadband (Wi-Fi) service provider. In addition, this technology will still suffer from some of the weaknesses of Wi-Fi and the cellular standard, like the expensive, inefficient bandwidth outside the Wi-Fi spot, and low security and only partial mobile support within the Wi-Fi coverage area.

 

 Intel's metropolitan Wimax network vision (Credit: Intel)
Intel’s metropolitan Wimax
network vision (Credit: Intel)

As a result of these limitations there is a need for a new standard which will enhance the existing standards for wireless broadband and give a broadband experience as it was meant to be: pervasive, mobile, fast, and cheap. This is where WiMAX comes into the picture. WiMAX tries to take the best part of cellular network access – the part that allows you to easily connect anywhere within your service provider’s wide coverage area – and to take the best part of your Wi-Fi experience – the fast speeds and a familiar broadband internet experience – and combine them into a new wireless standard. This new wireless standard is based on the IEEE 802.16 standard (also called WirelessMAN), and was named by the WiMAX Forum which was formed in June 2001 to promote conformance and interoperability of the new wireless standard. It is common to divide WiMAX into two sub-standards, one for fixed wireless data transmission, known as “fixed WiMAX” (based on 802.16d), and the other, known most commonly today as “mobile WiMAX” (based on 802.16e). Mobile WiMAX includes some improvements over fixed WiMAX by also supporting mobility futures. Throughout this article, the notation WiMAX will be used to designate the more advanced mobile WiMAX.

 

WiMAX is an enhanced broadband standard with mobile features which enables continuous connectivity and offers wide coverage. With WiMAX support of multiple antennas at a single base station and sometimes at the subscriber unit, the coverage of a single base station can reach tens of kilometers and the data throughput can increase by four times to tens of Mbytes/sec, compared to only a few Mbytes/sec using the most advanced cellular 3.5G technologies. The Third Generation Partnership Project, targeted the UMTS mobile phone standard to cope with future technology evolutions, suggested a competing standard to WiMAX called “Long Term Evolution” (LTE). Both LTE and WiMAX can be seen as pre-4G technologies and the technological differences between them are small as they both work on the same bandwidth and try to provide solutions to the increasing demand for enhanced broadband services with the most advanced wireless technology existing today. As Wi-Fi is already widely deployed and works effectively inside buildings (indoor), WiMAX is expected initially to co-exist with Wi-Fi (connect to and between Wi-Fi hotspots) and to be used in areas where it is more effective than Wi-Fi. WiMAX, as a broadband wireless technology, can also be used as an alternative to cable and DSL as a “last mile” broadband access, mainly in rural areas where there is no wired structure.

 

Wireless technologies comparison table 
Comparison of WiMAX with other broadband
wireless technologies. WiMAX can reach
the data throughput of Wi-Fi with the mobility
support of cellular networks like 3G.
With a higher number of antennas (up to four),
the coverage and throughput of the system ca

How Does WiMAX Work?

 

 WiMAX blankets large areas with broadband internet. Handover (transition) between WiMAX coverage areas and Wi-Fi hot spot areas enable the best experience whether you are in a Wi-Fi or WiMAX coverage area (Credit: Intel )
WiMAX blankets large areas with broadband
internet. Handover (transition) between WiMAX
coverage areas and Wi-Fi hot spot areas enable
the best experience whether you are
in a Wi-Fi or WiMAX coverage area (Credit: Intel)

The WiMAX network uses an approach that is similar to that of cell phones. A user sends data from a subscriber device to a base station mounted on a tower or tall building to broadcast the wireless signal in a channel called an uplink, and the base station transmits to the same or other user in a channel called a downlink. Unlike the user, who traditionally has limited resources, i.e. very limited transmission power, limited number of antennas, and limited computation capabilities, the base station can use higher transmission power, more antennas, and enhanced computation algorithms. WiMAX service providers deploy a network of towers that enable access over many miles and the WiMAX broadband service will be available anywhere within coverage areas. Coverage for a geographical area is divided into a series of overlapping areas called cells. When the user travels from one cell to another, the wireless connection is transferred from one cell to another.

 

The signal transmitted from the base station to the user or from the user to the base station through wireless channel faces attenuation in space, fraction, refraction, reflection from objects on the propagation path, and shadowing from walls or other barriers. As a result, the transmitted signal is distorted and sometimes splits into different replicas called multi-paths. The transmitted signal is commonly described by its structure in time, frequency (its frequencies and its bandwidth), and space. The receiver’s target at both uplink and downlink is to combat the signal’s distortion in order to perfectly recover the transmitted signal and enable reliable data transmission.

 

The transmitted signal in space, frequency, and time. Due to the physical phenomena of reflections from the surrounding objects on the propagation path, the transmitted signal is distorted and split into different multi-paths (Credit: Alvarion.com)
The transmitted signal in space, frequency,
and time. Due to the physical phenomena
of reflections from the surrounding objects
on the propagation path, the transmitted
signal is distorted and split into
different multi-paths (Credit: Alvarion.com)

At the heart of WiMAX technology stands several comprehensive concepts that can improve spectral efficiency (the number of information bits transmitted over a given spectrum resource) compared to other technologies.The first important relatively new transmission technique used by WiMAX is orthogonal frequency division multiplexed access (OFDMA), applied in order to efficiently exploit the frequency bands. The WiMAX Forum has defined three licensed “spectrum profiles” (transmission frequencies) of 2.3 GHz, 2.5 GHz, and 3.5 GHz to decrease the cost for manufacturers, as each spectrum profile may require different hardware infrastructures. Additionally, there is more unlicensed spectrum that is less frequently used by most telecom companies that prefer to control the entire available spectrum. Each spectrum profile has a related “bandwidth profile” which determines the channel’s bandwidth. The signal bandwidth is divided in OFDMA to small narrowband, equally and closely-spaced signal carriers used to carry data called sub-carriers. The transmitted data is then divided into several parallel independent data streams where each is allocated to another sub-carrier and all are transmitted at the same transmission interval. In the downlink path, the base station can transmit the data streams for different subscribers efficiently over consecutive sub-carriers. The independency of data streams is an important feature of OFDMA that prohibits several users’ data from interfering with each other and be multiplexed (transmitted in parallel simultaneously).  It is obtained by orthogonality of the different sub-carriers carrying the data at different bandwidths. Orthogonality is achieved when the peak of each signal sub carrier (in frequency) coincides with the nulls of other signals (due to the certain equal bandwidth of each sub-carrier) so that they do not interfere with each other. The OFDMA independent sub-carrier transmission enables power prioritization for different subcarriers according to the link quality (the measure of signal quality opposite to its distortion in the wireless channel); good quality sub-carriers will carry more data and bad sub-carriers will carry none. Furthermore, since the subcarriers’ bandwidth is narrow, it can combat better channel degradation caused by multi-paths. Consequently, OFDMA is considered a multi-path resistance.

The independency of data streams can be explained by the orthogonality of the different sub-carriers carrying the data at different bandwidths. Orthogonality is when the peak of each signal sub carrier (in frequency) coincides with the nulls of other signals (due to the certain equal bandwidth of each sub-carrier) so that they do not interfere with each other and can be transmitted simultaneously. (Credit: Alvarion)
The independency of data streams can
be explained by the orthogonality
of the different sub-carriers carrying
the data at different bandwidths.
Orthogonality is when the peak of
each signal sub carrier (in frequency)
coincides with the nulls of other signals
(due to the certain equal bandwidth
of each sub-carrier) so that they do not
interfere with each other and can
be transmitted simultaneously.
(Credit: Alvarion)

WiMAX, unlike WiFi, supports quality of service (QoS) mechanisms, which ensure a certain level of service to enable high-quality levels of applications such as VoIP or real time TV broadcasts. A dedicated data communication protocol centered at the base station is aware of the QoS application requirements and prioritizes the data streams and gives higher priority to data related to service that requires a higher QoS, like video streaming. This high priority is translated into transmission parameters such as higher transmitted power or more sub-carriers per user.

WiMAX plays an important role in both emerging markets and mature markets. There are more than 262 WiMAX operators covered in 91 countries. Many companies, from large communications equipment companies to smaller companies, are involved in developing and manufacturing WiMAX. Asia Pacific accounted for 26% of deployments, Europe 34%, the Middle East 16%, North America 11%, and the Caribbean and Latin America for 13%.

All of the above techniques working together increase coverage, user bandwidth, spectral efficiency (starting at 3.7 bits/sector/Hz), the number of users per WiMAX cell (in macro cells, up to thousands of “normal” subscribers), system stability, and costs. In a typical cell radius deployment of three to ten kilometers, WiMAX Forum Certified systems can be expected to deliver a capacity of up to 40 Mbps per channel for fixed and portable access applications; enough bandwidth to simultaneously support hundreds of businesses or thousands of residences with DSL speed connectivity.

All of these advanced features challenge WiMAX equipment manufacturers to build strong, dedicated, low-cost low power WiMAX base stations and chipsets for the portable units for advanced handsets and PC peripherals (PC cards or USB dongles) and other consumer electronics devices as game terminals.
WiMAX Today
Broadband is becoming a necessity for many residential and business subscribers worldwide. According to analysts, broadband services will see rapid growth from their current starting point. There were close to 350 million broadband subscribers worldwide at the end of 2007, up from 130 million at the end of 2004. WiMAX as a leading broadband technology is starting to make its niche in this market.
At the end of 2007, there were 1,650,000 WiMAX subscribers; currently WiMAX subscribers are estimated at 1.9 million according to the WiMAX Maravedis Telecom research company. Only a little over half were using WiMAX Certified technology (WiMAX Forum Certified means that a product or service based on the WiMAX standard from different companies will work together). 64% of the customers are residential and 36% businesses. Operators are competing progressively more head to head with DSL in suburban and urban areas. The WiMAX Forum is expected to certify 100 products during 2008 and more than 100 mobile certified products – across all profiles – by the end of 2008, rising to more than 1,000 by the end of 2011. The WiMAX infrastructure equipment market is expected by IDC to grow from $939 million in 2006 to over $3.5 billion in 2011.The WiMAX silicon market is expected by to grow from $34 million in 2006 to over $1 billion in 2011.

 WiMAX infrastructure equipment (base stations) and semiconductor (portable devices chipsets) market outlook. (Source, IDC)
WiMAX infrastructure equipment (base stations)
and semiconductor (portable devices chipsets)
market outlook. (Source, IDC)

 

In Asia, Taiwan is considered a leader in the development and deployment of WiMAX operability with six commercial WiMAX licenses awarded in July 2007 to six separate Taiwanese wireless communication providers. In regions like Taiwan, where users are spread out and the wireless traffic has to traverse a long distance, WiMAX technology provides a reliable, inexpensive solution for constant wireless broadband connectivity. In India, the newly announced changes to the 3G auction policy and the WiMAX spectrum auctions now prove that WiMAX is not simply a way to extend wireless but an entirely viable and complete technology in itself. WiMAX Forum estimated recently that India’s WiMAX market potential, including devices, to be worth $13 billion by 2012 with a base of 27.5 million WiMAX users. In the Pacific, in countries like Australia, WiMAX technology is perfectly suited for regional and rural areas with geography challenges and limited wireline footprints. In Africa, which has many developing countries, WiMAX technology provides the opportunity to connect the African people with internet and VOIP services faster and more affordable than wireline. In many European countries the first WiMAX deployments are taking place. Russia is the leading WiMAX market in Europe and the Russian WIMAX company Scartel LLC, along with Samsung Electronics, is about to begin trials of mobile WiMAX services in Moscow and St. Petersburg. In the United States, Intel, Google, Comcast, Time Warner Cable, and Bright House Networks recently joined forces to form a new venture, to be called Clearwire, to establish a nationwide WiMAX network. This venture gives WiMAX a better footing as a next-generation 4G wireless network. Sprint adopted WiMAX as their next generation broadband service. Sprint expects to complete the anticipated combination of its XOHM (Sprint’s 4G business unit) WiMAX business assets with Clearwire to form a new company in the fourth quarter. On August 10, 2008 XOHM, Intel, and WiMAX partners celebrated a new 4G broadband era with WiMAX service in Baltimore, and the slated next cities to be Chicago, Illinois and Washington, D.C. XOHM USB WiMax dongles by ZTE have also recently become available. The first laptops with built-in mobile WiMax wireless broadband are now available in the U.S. and Nokia is about to sell the new pocket size Nokia N810 internet tablet WiMAX edition, with a widescreen display and small keyboard, at select independent retailers in Baltimore. WiMAX-enabled notebooks will be available in the U.S. for connections to Sprint and Clearwire networks in 2009. Sprint will be the first and only wireless carrier to launch a dual-mode 3G/4G access device, expected in the fourth quarter of 2008.

 

MSI WiMax netbook
MSI WiMax netbook

Unlike service providers mentioned above, Verizon and Vodafone (the joint owners of U.S. based Verizon Wireless), on the other hand, plan to develop and deploy as their fourth generation mobile broadband network the competing technology – LTE. Which 4G technology will win, WiMAX or LTE? Both technologies have much in common from a technology standpoint and have many architectural similarities. Still, WiMAX has the following advantages over LTE: it benefits from strong allies including Intel and Google, and Network Operators is the largest segment of the WiMAX Forum. People might prefer to use WiMAX as the next generation of free Wi-Fi and in order to rebel against the traditional cell phone companies. WiMAX has already started regional and nationwide deployments while LTE may only enter the market in late 2009 (at the earliest). According to Nokia and Ericsson, their primary market – 3G operators – will be unlikely to adopt LTE until a few years later. LTE operator AT&T reiterated its position that its 3.5 (HSPA) and 3G network technologies still have a lot of life left in them, and that LTE technology would not be rolled out for at least another three years. The WiMAX Forum has already started working on the next backwards-compatible generation of the WiMAX standard, the 802.16m, which will be able to use even higher bandwidths and achieve higher spectral efficiency that will be able to compete with 802.11n in non-rural conditions.

Simens Gigaset SE68 SE68 WiMAX Express Card  (Credit: Simens)
Simens Gigaset SE68 SE68
WiMAX Express Card (Credit: Simens)

Recently, there are signs that the WiMAX and LTE camps are seeking a negotiated settlement to harmonize WiMAX and LTE. Participants from both the WiMAX and LTE camps and standards organizations have recognized the need to collaborate on developing communications. Vodafone is among the operators that have called for the merging of WiMAX and LTE because of the reduction in both conflicts and costs for the industry. The long-term trends in technology, regulation, ecosystem consolidation, and globalization contribute to the rationale that wireless systems should strive to achieve common air interfaces where feasible. Intel CEO Paul Otellini has also called for harmonization between WiMAX and LTE, pointing out the goals of unified broadband communications and common use of technologies. A head-to-head battle over the next few years would require an outlay of billions of dollars in equipment deployment that can be saved with the harmonization of the standards. The primary obstacle to achieving harmonization of WiMAX and LTE is simply the commercial self-interests of competing companies and manufacturers which prevent a common push forward. Intel will eventually provide combined support regardless of whether or not the standards groups achieve official harmonization about providing a multi-mode WiMAX plus LTE chipset for notebooks. Altair Semiconductor, an innovative mobile WiMAX chipset company, also uses the multi-mode WiMAX plus LTE chipset for other portable devices. The first example of standard harmonization comes from the base station manufacturer Freescale Semiconductor, who recently introduced the industry’s first multi-standard device.

 A bit of history - Alcatel WiMAX in CeBIT 2007
A bit of history
– Alcatel WiMAX in CeBIT 2007

Infonetics Research, the premier international market research and consulting firm specializing in data networking and telecom, believes that consumers will adopt dual-mode Wi-Fi notepads and phones (Wi-Fi and WiMAX) for use with home wireless networks, public hotspots, and municipal networks. Intel and Nokia are developing technology that is supposed to provide true uninterrupted broadband connectivity based on automatic undetectable switchovers from Wi-Fi to WiMAX. The American municipal wireless networking and intelligent transportation company Azulstar recently launched a high-speed WiMAX service based on Alvarion’s BreezeMAX 3650, which operates in the 3.65 GHz spectrum in New Mexico, which is supposed to support highly reliable services of up to 6 Mbps for home users and up to 100 Mbps for business connections. The launch is supposed to include the complete transition from Wi-Fi to WiMAX technology in Grand Haven, the first Wi-Fi city in the U.S, across New Mexico.

Whether it is LTE or WiMAX, the success of mobile broadband will be driven by the development of user-friendly applications and handsets. Applications driving the mobile broadband market include mobile music, multimedia messaging, gaming, and mobile TV. WiMAX kit vendor NextWave Wireless recently showcased its next generation mobile multimedia platform by demonstrating mobile TV, interactive media services, and digital audio – features it expects will drive the WiMAX market forward. Another company, Runcom Technologies, demonstrated the first internet TV set top box (STB) at the WiMAX Forum  Global Congress 2008 that took place last June in Amsterdam.

Interview with Eran Eshed, Altair Semiconductor

TFOT recently interviewed Eran Eshed, co-founder and VP of marketing and business of Altair Semiconductor, an innovative mobile WiMAX chipset company which recently won the Best of WiMAX World 2008 Award for their WiMAX chipset at the WiMAX World 2008 Conference.

Q: Can you say a few words about Altair’s background?
 Altair - fabless semiconductor WiMAX
Altair – fabless semiconductor WiMAX

A:

Altair is a fabless chip company developing ultra-low power and high performance 4G/OFDMA silicon solutions. The company was established almost four years ago, by a group of ex-Texas Instruments executives with exceptionally vast experience in the field of broadband semiconductor development. This team has developed during the past 10 years over 25 different complex mixed-signal broadband ICs, which shipped in millions of commercial products in the field. Prior to TI we worked together in a chip startup called “Libit Signal Processing,” which was acquired by TI in 1999, in what is still considered today as one of the most successful semiconductor acquisition in Israel’s tech scene.

Altair’s existing product lines focus around baseband and RF solutions for mobile WiMAX (802.16e) terminals, where our products today set the benchmark in terms of low-power consumption, small footprints, and low cost. Altair is the only company in the WiMAX space today which exclusively focuses on the battery-operated, small form, factor handheld device market segment, as opposed to other players which develop solutions for PC peripherals, notebook computers, and CPEs. In other words, we have a highly optimized solution which competes with other “one size fits all” solutions in our addressable market.
In parallel, Altair has been developing a 3GPP LTE chipset for almost two years now. Our LTE solutions are based on an architecture that is very similar to that of the WiMAX product, and leverages the field proven WiMAX technology we have developed for over three years. We expect to have one of the first commercial LTE ASICs in the market, and are cooperating with tier one operators and infrastructure vendors on this front.
The third product line in which Altair is involved is the homegrown Japanese technology known as XGP, which is being deployed by Willcom Inc., Japan’s PHS operator. Altair had been awarded leading supplier position to Willcom, based on our lowest power, flexible 4G architecture.
Altair is a private company, and has raised a total of $48M in three rounds of financing, making it one of the better funded early stage fabless chip companies in the WiMAX space. Our headquarters are located in Hod-Hasharon, Israel, and we have offices in the US and Korea, as well as representatives in Japan and Taiwan.

Q: Can you give the highlights of WiMAX technology, in your opinion?

A: Mobile WiMAX is a mobile broadband technology that combines the throughputs of fixed broadband technologies such as DSL and cable/DOCSIS with the mobility support of cellular technologies such as GSM or CDMA. WiMAX is based on a different type of modulation than these traditional cellular technologies, called OFDMA (orthogonal frequency division multiplexed access), which is a relatively new communications modulation scheme (at least from the practical application perspective) that allows extending the transmitted signal bandwidth from a few MHz to 20MHz and beyond, delivering throughputs of a few tens of Mbytes/sec, compared to only a few Mbytes/sec using the most advanced cellular 3.5G technologies, which are based on older types of modulation such as Wideband-CDMA. Using OFDMA, the implementation of advanced antenna techniques, such as MIMO or beamforming, become much simpler and efficient, translating into higher spectral-efficiency (i.e. the number of information bits transmitted over a given spectrum resource). The combination of high-speed access with high spectral efficiency means a high-quality experience to the user and a low cost of service delivery to the carrier.

Q: Can you see WiMAX more as next generation of Wi-Fi or more like enhanced mobile standard?

A: Historically, mobile WiMAX was developed as a fixed wireless broadband access technology. It later evolved to become a mobile standard, and adopted many elements from the cellular world. In that sense, it is clear the mobile WiMAX is disrupting the traditional cellular communications ecosystems and is perceived as a springboard for non-traditional cellular vendors, such as Cisco, or ones that were having a difficult time competing with the dominant 2/3G players, such as Samsung or Motorola, into the next generation of mobile wireless communications. Technologies which were perceived from day one as threatening by the cellular community, such as Qualcomm’s Flarion technology, were blocked and eliminated from the standards landscape; so WiMAX, from that perspective, was driven by Intel and their companions in a very strategically-smart manner, keeping it under the 2/3G radar until gaining enough industry momentum to become self sustaining.

Q: What about handover between WiMAX and Wi-Fi or mobile standards like 3G?

A: These items are extremely important for WiMAX’s success as a cellular technology since coverage is expected to be spotty in the early days of deployment and session continuity with existing/legacy technologies is the key to gaining user acceptance. Handovers between WiMAX and WiFi are defined under the IEEE framework (802.21 – media independent handover, or MIH) and handovers with 3G are already defined under 3GPP and 3GPP2, which are the 3G standardization bodies. The WiMAX Forum™ ™ standards are behind these efforts and it has dedicated task groups to ensure standards and interoperability are in place. In the world of everything going pure-IP, or semi-IP such as IMS- this is really more of a political issue than a technical challenge to resolve.

Q: Can you compare WiMAX to other technologies such as LTE?

A: There are several competing standards claiming to be “4G.” It is important to understand that they are all based on the same fundamental elements, namely OFDMA modulation, use of smart antenna techniques, and flat all-IP networks. WiMAX, in contrast to competing technologies such as LTE, benefits from a two year time-to-market advantage, an open vendor ecosystem, and the potential for disruptive business models that are already beginning to change the world of mobile communications.
There is a lot of misconception and too many marketing campaigns that are attempting to shape regulators’ and investors’ opinions on this topic. The simple truth is that WiMAX and LTE are similar in nature as they are based on the same air-interface and network architectures. Spectral efficiencies such as download speeds and cell-ranges are expected to be very similar, with each having subtle technical advantages and disadvantages.
What this really is, is a political battle of evolution versus disruption. In the long run, I believe that LTE will play a more dominant role in the 4G space as it had been adopted by the most of the incumbent and powerful carriers such as Verizon, Vodafone, China Mobile, and others. WiMAX, on the other hand, had been adopted by Sprint (and then spun-off and sold to Clearwire), KDDI, KT, and SKT as well as a variety of competitive LEC/cable operators and ISPs – a pretty strong lobby as well. Don’t expect to be bored in the coming few years.
As a company that develops solutions for both WiMAX and LTE, we feel like guys that sell shovels in a gold rush – maybe a little overstated, but definitely a very unique position to be in.

Q: Sean Maloney, head of Intel’s sales and marketing, has also called for harmonization between WiMAX and LTE, pointing out the goals of unified broadband communications and common use of technologies. Do you think harmonization between these 4G technologies is possible? Needed?

A: I think it is possible, although not very likely. This harmonization proposal is about 3GPP adopting WiMAX as the TDD (time division duplexing) version of 4G while keeping LTE as the FDD (frequency division duplexing) version. When you peel off the technical arguments, you’re left with the strategic and political agendas of the stakeholders, which in my view today, are not in favor this harmonization.
While this debate keeps heating up, China Mobile (the largest cellular carrier in the world) published an LTE-TDD RFI recently, rendering a WiMAX 3GPP 4G-TDD version even more unlikely.

Q: Is WiMAX in competition or in cooperation with wireline technologies?

A: Wireless technologies in general face challenges competing with wireline technologies on quality of service – wires are a more stable and predictable medium to communicate over, and WiMAX is no different in this regard. Where WiMAX becomes really interesting is where (a) there is no wireline infrastructure, or when the infrastructure is available but suffers from low quality and high maintenance costs, or (b) where mobility is desired. I really don’t think WiMAX competes with DSL, cable, or fiber in the access space; it is much more complementary in covering the mobility aspect.

Q: What about commercial success of these standards? Do you think there is a need for further advanced standards like 802.16m which will be able to use even higher bandwidths and achieve higher spectral efficiency?

A: I think that by all standards mobile WiMAX is a success story, considering where it came from and its short history. Compare WiMAX to UWB for example – a great example of how conflicting interests almost killed a great technology, and that game is not over yet.
It is technology’s nature to evolve and improve, regardless of the concrete demand for it to do so. It is difficult for us today to anticipate the technology requirements that will exist for broadband service delivery five or ten years from now; however, it is clear that they will increase, not the other way around.

Q: What is in your forecast for WiMAX’s near future and, in particular, under economical recession?

A: In the near future, the service providers’ motivation is even more important than that of consumers since there is no application yet ready that consumes 10Mbps. The WiMAX service provider wants to increase monthly revenue and improve profitability because the voice revenue is declining. As a result, service providers want to offer advanced services. Since these services are heavy bandwidth consumers, they are uneconomical to deliver using current 3G technology. This is where WiMAX offers something that does not exist today – low cost/bit, high spectral efficiency which ultimately translates into solid and profitable business models. Recessions, such as the one we are witnessing, are not a supportive environment for new and emerging technologies to root, so is not going to be easy for WiMAX carriers and ecosystem vendors. The flip side of this is, however, that WiMAX has crossed a critical-mass maturity line while LTE is still behind, and is therefore in a position to entrench itself yet deeper before the pink color is back to investors’ cheeks and LTE could attempt to catch up. Besides, WiMAX has gained significant traction in geographies like Africa, the Middle East, and southeast Asia, which are much less affected by the crisis than American, European, or Japanese markets, so the exposure for WiMAX in this environment is smaller.

 

 

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