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The rise of wireless broadbandBy Fabio Leite, Counsellor, Fixed Wireless Systems, Radiocommunication Bureau, ITUAccessibility with affordability Access system, network and applications are the pillars forming the infrastructure of the global information society. However, it is only when all these three layers become accessible and affordable for all peoples in the world that one can practically speak of global information society. Access to the network, offering capabilities for advanced Internet services and multimedia applications, is provided by high capacity systems known as broadband. Wired systems (including copper, cable, optical fiber) are common means of providing high-speed network access for homes and business premises, particularly in downtown and urbanized areas where telecommunications infrastructure is available. The costs associated with the deployment of the access and network infrastructures are often outside the reach of many economically under-developed regions. This is particularly the case in rural and remote areas that have lower subscriber density or geographic challenges such as mountainous terrain, large bodies of water, or jungles. For this reason, ITU has been promoting the use of most suitable technologies, including wireless access systems, as a way to timely and effectively address these difficulties. Is it really broadband? Most important is to characterize broadband as a means to provide network access to information services at higher capacity than the basic dial-up mode over the switched telephone line. This concept provides a differential increment to stimulate technological progress and brings the user’s connectivity up to capacity levels compatible to those required by data, multimedia, downloading and other applications demanding more technical resources than simple voice communications. Broadband has been referred to as the infrastructure of the knowledge economy. Countries around the world have appointed broadband networks as crucial infrastructure for achieving their social, economic and scientific goals. However, in some countries the take-up of broadband has been disappointingly slow, and in many economies around the world it remains below expectations, although there are significant exceptions, most notably the Republic of Korea. Broadband for everybody
![]() At the global level, the ITU Telecommunication Development Sector initiated in 2002 a comprehensive analysis aiming at identifying the technical, economic, and development factors influencing the effective deployment of broadband access technologies and applications. A final report is expected in 2004. Under its New Initiatives Program, the ITU studied the strategic and policy aspects of deploying broadband. Global standardization and frequency spectrum issues relating to broadband systems are also being discussed in the technical sectors of ITU. The Global Standards Collaboration, a group which mission is to exchange information between participating standards organizations to facilitate collaboration and to enhance the process of global telecommunication standardization in the ITU, met in 2003 to stress the need for cost-effective solutions to support delivery of broadband services to rural and remote area communities (see GSC-8 Resolution). Global Standards Collaboration RESOLUTION GSC-8/8: Broadband Services in Rural and Remote Areas (27 April – 1 May 2003, Ottawa, Canada)considering
Deploying broadband The most common means of broadband access uses the installed wireline telecommunications or cable infrastructure, like the digital ISDN or the analogue telephone network, including leased lines for business users, or cable TV network. In recent years a number of other solutions based on wireline technology like DSL or radio waves like wireless LAN, have become commercially available to provide broadband access. The breakdown of technology for the top 15 broadband economies shows that DSL over the analogue switched phone lines and analog modems over TV cables are the most deployed technologies (see Fig.2). In the US, projections2 indicate that by 2006, cable will have grabbed 33.1 million broadband homes versus DSL’s 11.4 million; an additional 5 million homes are seen as choosing new broadband technologies, such as fixed wireless. ![]()
Wireless access This tendency boosted by technological progress is reflected in the ITU statistics4, which indicate that the number of wireless subscribers in the world exceeded wireline ones already by the end of year 2002. And the best performing countries are as diverse as Finland and Cambodia. Wireline solutions will continue to prosper in the developed parts of the world, which are well served by the telecommunications infrastructure. On the other hand, in rural areas, sparsely populated regions or territories underserved by telecommunications networks, wired options will certainly not represent an economically or technically viable approach for the timely provision of broadband access. In many countries or regions, particularly in the underdeveloped or developing parts of the world, penetration of household cellular phones and radio-wave television is very high or growing fast. It is likely that this customer base will never opt for telecommunications services based on wireline solutions making it attractive to explore possibilities to offer them broadband access through the cellular or TV wireless infrastructures once they are enhanced to provide high capacity digital services. In general, the several options available for broadband wireless access could be examined, e.g., fixed or mobile systems, satellite, radio-wave digital TV, etc. Systems for broadband wireless access WLAN International standardization started in the late 1980s and early 1990s and in 1996 IEEE standards committee released its first WLAN standard: 802.11, which has since become known as Wi-Fi (for wireless fidelity). In Europe, ETSI has also established standards for WLAN applications known as HiperLAN (for High Performance Radio Local Area Network). Fig. 3 shows the current standards and frequency spectrum associated to WLANs. ![]() Spectrum allocations for WLAN vary in different parts of the world. The 2.4 GHz band was first made available in North America in mid 1980s; in Europe, CEPT allocated the band in 1996. Today, virtually all countries worldwide permit the operation of devices in this band. The situation is rather more complex in the 5 GHz band where the sub-bands 5.15-5.35 GHz and 5.47-5.725 GHz were allocated in Europe and North America in the late 1990s; the upper part in the 5.725-5.825 GHz is available in North America but can only be used in Europe with strict power limitations. Worldwide governments members of ITU decided during the World Radiocommunication Conference 2003 (WRC-03) on rules for the coordinated use of parts of the 5 GHz bands (5.15-5.35 GHz and 5.47-5.725 GHz). WLANs based on IEEE 802.11 standards have been widely deployed in the world for private (e.g., at home or office) and public use (e.g., in airports, train stations, cafes, shopping malls, known as hotspots Wi-Fi). From about 12000 hotspots available to public in 2002, predictions indicate that this number can grow to over 145,000 in 20075. More than $2 billion venture capital was invested in the Wi-Fi industry and worldwide sales of Wi-Fi equipment may reach $1.67 billion in 2003. In one interesting use of private WLAN, in apartment buildings, residents are setting up Wi-Fi “hotspots” to share capacity amongst neighbors from a single broadband connection (e.g., wired – cable or DSL, or satellite). WLAN has become commonplace in the office environment as companies have found that their introduction is cutting their telecom costs and helping employees be more productive. Security is still a concern for WLAN use and technical solutions are expected soon. “Voice over Wi-Fi” and location-based services are also being considered as promising innovations in the WLAN booming market. Although WLAN has been seen as a possible competitor of other broadband wireless systems like 3G/IMT-2000, practice has shown that WLAN devices are actually a complement to their roll out, at least in the longer term. It is noted that as a general condition of operation, devices operating on a license-exempt basis, like WLANs in the 2.4 and 5 GHz bands, shall not cause any harmful interference to authorized services and must accept any interference that may be received. For example, the bands 2 400-2 483.5 MHz and 5 725-5 875 MHz are designated in many countries for industrial, scientific and medical (ISM) applications and WLAN operating in these bands could be subject to interference from those applications. Despite the inherent limitations on coverage and quality of service, the accelerated rate of implementation of private and public WLAN has given rise to speculation on their potential role in the provision of broadband access. At “The Wireless Opportunity For Developing Nations” conference (New York, 26 June 2003) organized by the Boston-based Wireless Internet Institute and the United Nations Information and Communication Technologies Task Force, which debated what wireless technology could do for developing nations, the UN Secretary General conveyed the following comment: “It is precisely in places where no infrastructure exists that Wi-Fi can be particularly effective, helping countries to leapfrog generations of telecommunications technology and infrastructure and empower their people.” Fixed Broadband Wireless Access (BWA) Spectrum and licenses have been assigned in a number of countries for fixed-BWA applications but they have had limited reach so far, in part because of the multiplicity of solutions based on proprietary technologies. Fixed-BWA networks are based on a central radio base station, which communicates with equipment located in a multiplicity of subscriber premises in the surrounding area. For this reason, such systems are often referred to as point-to-multipoint (P-MP) systems. The most widely used generic name for this fixed-BWA category is LMDS (for Local Multipoint Distribution Service). This term was coined in the US for the initial proposal of a wireless competitor to cable television, planned for the 28 GHz band. As planning progressed, it became increasingly clear that the rapidly growing telecommunications traffic, notably including Internet, presents more promising fixed-BWA business opportunities than video distribution, and that all the available frequency bands in the 24.25-31.3 GHz range can be used for the same new kind of service. Similarly, the 40.5-43.5 GHz band was initially targeted for MVDS (Multipoint Video Distribution System) in Europe and has been further harmonized within Europe for Multimedia Wireless Systems (MWS). The LMDS development parallels the evolution of multichannel MMDS (Multipoint or Microwave Multimedia Distribution System) in the 2.5-2.7 GHz band from video distribution to digital fixed-BWA applications. MMDS was originally a one-way broadcast technology, intended to provide wireless competition for cable TV. Newer two-way equipment allows MMDS to be used for broadband wireless access. In 1996, the USA auctioned the band 2 150-2 680 MHz for Multipoint and/or Multi-channel Distribution Services (MDS), popularly referred to as "Wireless Cable," which is a service that permits the delivery of video programming to subscribers through microwave transmitting and receiving antennas. The channels allocated to MDS are generally used to provide a multi-channel video programming service that is similar to cable television. As fixed-BWA systems evolve, standards will become increasingly important. Standards development currently underway includes activities by the IEEE, ETSI, ATM Forum, DAVIC, and ITU. Fig. 4 depicts the standards development in IEEE and ETSI for fixed-BWA and contains reference to ITU activities on this area. In February 2003, IEEE WirelessMAN (wireless metropolitan area network) standard for licensed and license-exempt spectrum in the 2-11 GHz band (802.16a) was approved. Compliance and interoperability testing of WirelessMAN air interfaces, from 2 to 66 GHz, is supported by the Worldwide Interoperability for Microwave Access (WiMAX) Forum. ![]() Spectrum allocation is a critical factor in fixed-BWA deployment. Efforts are being undertaken to harmonize the spectrum allocated for fixed-BWA on a global scale in ITU and on a regional scale, particularly in Europe (see CEPT ERC Decisions and Recommendations), in the Americas (see CITEL PCC Recommendations) and Asia-Pacific (see ASTAP expert group on FWA). Despite these efforts, spectrum is not harmonized worldwide as seen in Table 2 detailing spectrum allocations in different regions of the world, their status and availability, and technical characteristics and capabilities. One area of growing interest for fixed-BWA applications is the provision of rural communications. Several programs and projects are promoting the use of wireless solutions for broadband access in rural areas. The US government Joint Federal Rural Wireless Outreach Initiative and the FCC spectrum decisions taken in 2003 were intended to promote the continued rapid and efficient deployment of quality wireless services in rural America. As recently reported6, a few countries such as Botswana, Ghana and Nigeria are currently auctioning frequencies for specific fixed-BWA applications. The case of South Africa is one lagging behind as the local loop for universal services is yet to be deregulated. Other countries, for example Lesotho and Morocco, are examining the technology seriously with local companies requesting information for systems vendors. Fixed-BWA wide-scale commercial deployments are happening in Botswana, South Africa and Nigeria. Nevertheless, small-scale fixed-BWA private network deployments are occurring in many countries like Mauritania, Egypt and elsewhere. They are, however, less publicized since they either serve private networks purposes (mining, oil companies for example) or are small ISP deployments. In Nigeria, eight firms out of 29 emerged as winners of 8 FWA licenses, at a total cost of N1.645 billion, in an auction conducted by the Nigerian Communications Commission (NCC) in 20027. This provided momentum and visibility to Africa as the next continent for fixed-BWA deployments. The Irish Commission for Communications Regulation (ComReg) announced on 6 November 2003 its intention to offer 59 new Fixed Wireless Access Local Area licenses in the 3.5 GHz band, as a further stimulus to the development of broadband services in Ireland8. These license offers are made following the completion of the first phase of a two phase licensing scheme for the provision of broadband services on a local area basis. Industry Canada announced a spectrum auction in January 2004 for licences in the 2 300 MHz and 3 500 MHz bands9. It includes five licences in each of 172 service areas across the country (with the exception of the 3 500 MHz licences for Vancouver Island), totalling 848 licenses, to be auctioned for companies to provide innovative wireless services, such as high-speed Internet. The purpose of this licensing process is to facilitate the growth of Wireless Communications Services (WCS) in the 2 300 MHz band and FWA in the 3 500 MHz band in both rural and urban areas, as well as to facilitate the implementation of new and innovative services.
Still many countries have yet to provide a legal framework for fixed-BWA licenses and competition at the local loop for universal services, which include fixed voice applications. Fixed-BWA will certainly contribute a major role in the spread of voice and data services across businesses and citizens, particularly in rural and underdeveloped areas. IMT-2000 IMT-2000 is able to offer broadband access to the mobile or fixed user with speeds from 2 Mbit/s in the stationary mode. IMT-2000 deployment is accelerating as explained in ITU News magazine no. 6 (July-August 2003) and as more and more countries have rolled out their 3G networks, it will make up the main wireless infrastructure for broadband access. It is important to note that different technologies, such as WLAN, short-range connectivity systems, and IMT-2000, may be present in a single device operating across various networks at any particular time. In the future operators may deploy a mix of technologies that could, at various stages in time, incorporate cellular, WLAN, digital broadcast, satellite and other access systems. This will require the seamless interaction of these systems in order for the user to be able to receive a variety of content via a variety of delivery mechanisms depending upon the particular terminal capabilities, location and user profile. This “optimally connected anywhere, anytime” view is the core basis of the ITU vision for the future development of IMT-2000 and systems beyond IMT-2000 and could be realized by a network comprising a variety of interworking access systems connected to a common packet-based core network. Satellite broadband
High speed satellite Internet access solutions giving broadband and email connection via direct two-way interactive transmit-receive very small aperture (VSAT) terminals is now possible in a large market across the world following a maturing of the technology. Fast satellite Internet web page downloads, email, ftp file transfers and streaming video and audio are achieved with broadband speeds of typically several hundred kbit/s; upload, return path, rates are generally less than 128 kbit/s. In September 2003, Europe launched E-bird, the first satellite designed to offer two-way high-speed Internet service across the entire continent. E-Bird has been optimized for two-way broadband Internet service and can be accessed with a dish antenna of around one meter in diameter. The satellite carries a payload of 20 transponders that operate in the Ku band (11-14.5 GHz) and has four downlink beams. Four of the transponders will receive signals from users and connect them to the Internet while the other 16 transponders will handle downstream signals from the Internet to users. ITU members recognized the potential satellite telecommunication technology has to accelerate the availability of high-speed Internet services in developing countries, land-locked and island countries, and economies in transition. As a consequence, a new topic for ITU Radiocommunication Study Groups has been recently included in the current work program to consider technical and operational characteristics that could facilitate the mass production of simple terminal equipment (i.e. VSAT) at affordable prices and spectrum related matters for the provision of global broadband satellite services. South West Broadband ProjectExasperated by the almost complete disinterest of the telecommunication companies to provide broadband capacity outside of the larger areas of population, the South West Regional Authority of the Republic of Ireland decided to see if anything could be done by themselves. Their research pointed to the growing preference for wireless around the globe, and the availability of broadband from satellites. The conclusion was to combine both, with an intelligent interface. The South West Broadband project commenced operations in January 2003.The project aims to independently and rigorously test satellite as a means of accessing broadband, to validate the technology across a range of field trials in areas of e-government, business support, e-medicine and distant education. It aims also to evaluate the suitability of the technology, together with its usability, sustainability and reliability.One of the most exciting elements of the program is the rollout of WLANs, linked to the satellite systems in peripheral towns. This program is becoming a notable success, where by employing a combination of satellite and WLAN technologies, is giving broadband access to individuals and small-and-medium enterprises (SMEs) across communities.The typical cost of providing this service to a town of three thousand persons is of the order of €20 000. Individuals and SMEs experience a connectivity of approximately 11 Mbit/s via technology linking both satellite and WLAN systems. This technology package has been developed by a technical partner and provides a seamless interface between users and the WWW. Full details of the project are available at http://www.swra.ie/broadband. Digital TV The existing digital TV broadcasting services transmit Internet data by means of special Internet inserters and devices for cyclical presentation of websites (“sites carousel”). But the web pages transmitted in this way can be presented with a proper quality only by a PC monitor. At the same time, for many countries broadband access to the Internet by means of TV broadcasting without making use of a PC is of great importance and is a part of their efforts in bridging the digital divide. This calls for the reformatting and rescaling of the web pages transmitted in the digital TV broadcasting data stream in the user’s set top box. The ways to ensure presentation of a web page on an ordinary TV set screen are currently being study by the ITU Radiocommunication Study Groups. The case for global standardization The debate on the pros and cons of global standardization of wireless communications has never been so bitter than during the IMT-2000 development, prompted by the industry hunt for global markets and challenged by the liberal market-driven bias ignited by spectrum auctions. The excitement seems to have come down in the 3G industry bringing its players back into the usual hardships of the competitive wireless market. While getting to market is high priority in the broadband wireless industry, operators know that staying there over the long run requires a standards consensus. Standards will ultimately lower the cost for both vendor and customer equipment, making wireless broadband an attractive choice for price-sensitive customers. Wireless operators have repeatedly expressed their strong desire for broadband wireless systems based on interoperability and non-proprietary standards. This claim is well voiced by Roger Marks, Chairman, IEEE 802.16 Working Group on BWA: “New technologies for the wireless Internet will greatly expand the availability of broadband access. The success of new technologies is closely linked to the development of interoperability standards, which define the marketplace, improve the equipment, bring down the cost, and expand the applicability to lower-volume users. Successful standardization efforts are open, global, and driven by technical considerations.” ITU has an enormous responsibility to respond to this requirement from governments, industry and users for the timely development of a global agreed framework for the worldwide deployment of broadband wireless access systems. ITU coordinated efforts and related activities on wireless broadband are described in the Wireless Access Systems website. The importance of broadband access as the core element of information and communication infrastructure was stressed in the process of preparation for the World Summit on the Information Society. Agreement has been reached on the WSIS Plan of Action, which is seen as an evolving platform to promote the Information Society at the national, regional and international levels. It is noted that, amongst others, the Plan calls governments to “develop and strengthen national, regional and international broadband network infrastructure, including delivery by satellite systems, to help in providing the capacity to match the needs of countries and their citizens and for the delivery of new ICT-based services.” The potential of society to improve productivity and the quality of life is growing due to the technological developments of broadband access. International cooperation will be key to foster coordinated actions on the global scale to address the significant economic and social opportunities that the widespread of broadband access infrastructure will provide to the global information society. Footnotes
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