Over the past year, Wi-Max has gained onsiderable traction in the technology market. The number of commercial deployments across the world is increasing, and vendors are reiterating their commitment to the technology.

Regarding adoption, Wi-Max will clearly achieve some level of success, particularly in the emerging markets.However, given that the majority of cellular networks around the world are GSM, the road to mass adoption of mobile Wi-Max is likely to be challenging. The following are the benefits and challenges of Wi-Max vis-à-vis competing technologies...

Benefits

Wi-Max is the first major mobile standard to offer all-IP as a standard feature.Though 3GPP will get there eventually, the technology employs a complicated and expensive core network.

Most of the existing wireless technologies suffer from limited range and coverage (usually a few hundred metres around the base station), which necessitates an expensive combination of technologies (wired and/or wireless). Moreover, these can provide only line-ofsite (LoS) coverage. On the other hand, Wi-Max provides wide coverage and can be deployed not only as a point-to-multipoint last mile connection but also as part of the backhaul to the public switched telephone network (PSTN) and internet access points.

Wi-Max, thanks to its orthogonal frequency division multiplexing (OFDM) technology, has been optimised to provide excellent non-LoS coverage (up to 15 km around the base station) as well as long-range transmission up to 50 km under LoS conditions. Wi-Max, therefore, offers a huge improvement over all existing broadband wireless technologies.

According to ABI Research, since energy costs constitute the third largest share in the operating expenditure (opex) of service providers, and since fluctuating energy costs are a significant concern, carriers need to move from a traditional cellular-only approach to one that integrates Wi-Max and metro Wi-Fi. This is because with the introduction of mobile broadband and the corresponding increase in data uptake, the energy required per subscriber will increase and so will the energy opex per subscriber. From a pure coverage point of view, Wi-Max is twice as energy cost effective as wideband CDMA (WCDMA). Taking data traffic into account, Wi-Max can accommodate 11 times the current average data consumption and still be more energy cost efficient than WCDMA or high speed downlink packet access (HSDPA).

According to Wi-Max operator Clearwire, Wi-Max networks are cheaper to operate. Improvements in chip technology have enabled Wi-Max vendors to push the envelope on software, thereby making hardware cheaper, faster and more energy efficient. Instead of using coaxial cables, most Wi-Max installations use optic fibre which is easier to install and support. Also, the base station equipment is so small that it can be installed directly on a tower or rooftop, thereby eliminating the cost of an enclosed shelter.

Another advantage of Wi-Max is its ability to bypass the copper loop as well as the leasing costs and controls that come with it. There are also cost savings at the customer premises; manufacturers and operators are already looking at home-gateway customer premises equipment (CPE) with price points under $100, down from an average of $500 as recently as two years ago.

Intelligent antennas with a new interface for Wi-Max are on the road map for mobile operators. But operators who already have a substantial number of towers are unlikely to deploy the antennas in the short term. They usually scale capacity on new services and air interfaces gradually.

The availability of a large ecosystem of products will be critical for the success of the technology. Lenovo has launched four Wi-Max laptops and will launch another five in the near future. Similarly, Asus has launched three Wi-Max laptops priced between $1,300 and $1,400, and is likely to launch three more soon. Toshiba also intends to add more notebooks to its WiMax line-up as coverage expands.

Even as questions are being raised about the viability of mobile Wi-Max visà-vis long term evolution (LTE), a key advantage that mobile Wi-Max has is time-to-market, as the technology effectively arrived in 2006 with the launch by South Korea's WiBro. On the other hand, LTE networks are expected to start rolling out commercially in September 2010.While the market waits for LTE, Wi-Max will serve as a "data overlay" for 3G, meant for delivering data where 3G speeds are inadequate, while the cellular network continues to handle voice.

There is a great opportunity for WiMax in India, which is expected to have the world's largest Wi-Max deployment by 2012. The technology will be very effective in the rural areas as its base stations are particularly cost effective in the 50 km range.

With information and communication technology (ICT)-enabled kiosks or common service centres being set up in rural India, Wi-Max can play a major role in delivering various services in such regions. These include online bill payment, delivery of agriculture, health care and entertainment services, and solutions for e-commerce including commodity price information, online trading and banking transactions.

Challenges

Adoption by carriers, availability of spectrum, maturity and equipment availability are some of the challenges faced by new technologies. Wi-Max is no exception.

Notwithstanding rapid uptake in 2008, industry experts are of the view it will become clear in 2009 whether Wi-Max can hold its own against competing technologies like HSPA and LTE, or whether the high investments in Wi-Max will come to naught.

The biggest challenge to Wi-Max comes from other technologies. Much of the early success is likely to be in emerging markets as Wi-Max will face tough competition in regions with established broadband services. According to research agency In-Stat, most 3G carriers are not likely to deploy Wi-Max in the near term.This is clearly the case in Europe where there are well-established 3G networks.To wean subscribers from incumbent providers, Wi-Max will need to provide superior service.

With over 16 operators investing in deploying LTE around the world, LTE is likely to become the dominant 4G technology amongst Tier I mobile operators.Though the technology lags behind WiMax in maturity and is not likely to be available for nearly two years, LTE will be an upgrade to the current cellular networks and will not require completely new networks, as is the case with Wi-Max. It will also have a substantial scale advantage when it comes to cost.

As a result, mobile Wi-Max has been gradually losing momentum to LTE. In fact, IMS Research's study shows that mobile Wi-Max will struggle to gain traction with operators and will remain a niche mobile technology.

According to Frost & Sullivan, unless spectrum auctions and commercial mobile Wi-Max rollouts (compliant to Wave 2 Phase 2 certification) happen fast, the market for the broadband wireless technology will be insignificant.

Researchers also suggest that Wi-Max is facing challenges that are likely to make it unfeasible as a mobile access technology.For example, Wi-Fi is well suited for providing indoor wireless broadband and, with the emergence of 802.11n –­ which includes multiple input, multiple output –­ would offer throughputs far better than mobile Wi-Max.

With respect to outdoor mobile broadband, subscribers would expect mobile WiMax to seamlessly hand off to cellular networks in the absence of Wi-Max reception. In reality, this is not possible as mobile Wi-Max is not backward compatible with the existing cellular technologies.

Mobile Wi-Max is also not optimised to simultaneously handle data and voice applications as efficiently as HSPA or 3G LTE. It is therefore not clear whether consumers will accept the initial client devices for mobile Wi-Max (ultramobile PCs or tablet devices), as they may not want one cellular-based device for voice and another mobile Wi-Max-based device for personal broadband. On the other hand, HSPA coupled with Wi-Fi can handle voice and data through a single device. The number of dual-mode Wi-Fi/cellular mobile phones is on the rise, with newer models emerging at lower costs and with better battery life.

In India, Wi-Max has the support of key operators like Bharti Airtel, Tata Communications and Bharat Sanchar Nigam Limited. However, regulatory uncertainty and lack of spectrum continue to hamper the technology's growth.The auction for Wi-Max spectrum has been postponed several times and a decision on the reserve price for spectrum is yet to be made. The other key hurdle is the abysmal PC penetration rate in the country. Also, in a price-sensitive market like India, where there is a continuous downward pressure on average revenue per user, the success of Wi-Max will hinge upon CPE prices and the availability of affordable end-to-end connectivity, including the computing platform.

Considering the benefits as well as the challenges, the jury is still out on the longterm success of Wi-Max and its ability to emerge unscathed in its battle against the new standard –­ LTE –­ which has been tabled as a 4G technology.