Praise for Fundamentals of WiMAX

22 Chapter 1 • Introduction to Broadband Wirelesscapabilities. For example, DSL services in the United States already offer 3Mbps–6Mbps ofdownstream throughput to the end user, and solutions based on the newer VDSL2 standard willsoon deliver up to 50Mbps–100Mbps, depending on the loop length. With incumbent carrierspushing fiber deeper into the networks, the copper loop lengths are getting shorter, allowing forsignificantly improved data rates. Cable modem technologies offer even higher speeds thanDSL. Even on the upstream, where bandwidth had been traditionally limited, data rates on theorder of several megabits per second per user are becoming a reality in both DSL and cable. Theextremely high data rates supported by these wired broadband solutions allow providers to offernot only data, voice, and multimedia applications but also entertainment TV, including HDTV.It will be extremely difficult for broadband wireless systems to match the rising throughputperformance of traditional broadband. WiMAX will have to rely on portability and mobility asdifferentiators as opposed to data rate. WiMAX may have an advantage in terms of networkinfrastructure cost, but DSL and cable benefit from the declining cost curves on their CPE, dueto their mature-market state. Given these impediments, fixed WiMAX is more likely to bedeployed in rural or underserved areas in countries with a mature broadband access market. Indeveloping countries, where existing broadband infrastructure is weak, the business challengesfor fixed WiMAX are less daunting, and hence it is much more likely to succeed.Differences in global spectrum availability: As discussed earlier, there are considerabledifferences in the allocation and regulations of broadband spectrum worldwide. Although2.5GHz, 3.5GHz, and 5.8GHz bands are allotted in many regions of the world, many growthmarkets require new allocations. Given the diverse requirements and regulatory philosophy ofvarious national governments, it will be a challenge for the industry to achieve global harmonization.For WiMAX to be a global success like Wi-Fi, regulatory bodies need to allow full flexibilityin terms of the services that can be offered in the various spectrum bands.Competition from 3G: For mobile WiMAX, the most significant challenge comes from 3Gtechnologies that are being deployed worldwide by mobile operators. Incumbent mobile operatorsare more likely to seek performance improvements through 3G evolution than to adoptWiMAX. New entrants and innovative challengers entering the mobile broadband market usingWiMAX will have to face stiff competition from 3G operators and will have to find a way to differentiatethemselves from 3G in a manner that is attractive to the users. They may have todevelop innovative applications and business models to effectively compete against 3G.Device development: For mobile WiMAX to be successful, it is important to have a widevariety of terminal devices. Embedding WiMAX chips into computers could be a good first stepbut may not be sufficient. Perhaps WiMAX can differentiate from 3G by approaching the marketwith innovative devices. Some examples could include WiMAX embedded into MP3 players,video players, or handheld PCs. Device-development efforts should also include multimodedevices. A variety of broadband systems will likely be deployed, and it is critical that diversenetworks interoperate to make ubiquitous personal broadband services a reality. Ensuring thatdevice development happens concomitant with network deployment will be a challenge.