WiMax: A matchless offer to wireless communication

Date:   Saturday , May 31, 2008

Challenges in improving rural tele-density and cost effective wireless communication for the masses can be achieved through some options, and WiMax (Worldwide Interoperability for Microwave Access) is the best suited for developing markets like India. Though globally WiMax has about 10 million subscribers, it has a vast potential to mobilize a major portion of the rural market in the developing economies.

Though globally WiMax is still in various stages of market adoption, India has been testing the technology for a while now. In the developed markets, it would be a challenge to provide seamless roaming solutions for nomadic and mobile users across various technologies such as WiFi, GSM, UMTS, and CDMA. While the challenges continue to be in various stages across the market, continuous development from the base station to CPE has been a key factor in the growth of WiMaxís market. One of the unique features that WiMax offers for a market like India is RAN sharing which will offer at least 30 percent savings for Greenfield Service Providers. This will further challenge the ARPU levels for voice using other technologies such as GSM and CDMA, and enhance the data revenue drivers.

Challenges in providing indoor coverage in metros and other similar dense clutters of users are made flexible and cost effective; and the advanced radio features of 806.12e are supplemented by smart antennae or Adaptive Antennae System (AAS) and the link budget. The MIMO (multiple input and multiple output) and AAS support advanced RF features.

In India, mobility in the rural segment will become a social and business activity that would change the lifestyle of the rural citizen. On the other hand, urban requirements will grow to demand access anytime anywhere to personal services environment. Besides, advanced 4G features such as video calls are feasible in WiMax networks, which are not so successful over mobile broadband networks or Internet. In addition, WiMax offers a very low latency for video call (below 400 ms delay) and high resolution (QVGA) voice and video. WiMax fundamentally provides a sound platform to deliver a true multimedia experience.

In a typical WiMax architecture as shown here, the technology offers CAPEX optimization at Core, Edge, access, customer premise infrastructure (CPEs and IADs), and also offers cost effective backhaul.

Let us briefly analyze the key benefits of a WiMax network from the following perspectives:
* Standards compliant and security
* Full mobility (through Alcatel-Lucentís 802.16e standard BTS)
* IP compatible
* Mass and rapid deployment
* TCO benefits

Standards compliancy: With the introduction of the physical layer (PHY) and SOFDMA (Scalable OFDMA), IEEE 802.16e has revolutionarized the technology and itís growth. The WiMax Forum initiatives on multi-vendor product interfaces have enhanced the adaptability of WiMax to existing networks. The IOT (Inter-Operator Tariff) requirements have been understood at early stages and most of the vendors are active participants in the IOT activities.

On the technology development roadmap, WiMax is positioned between LTE, UMB and others, wherein the data speed will progressively increase from the existing 64 kbps - 2 mbps to 100 mbps. This will enable service providers to develop various revenue models based on bundling of a wide range of applications that require different bandwidths.

Security being one of the key requirements of current and future networks, WiMax offers encryption based authentication and CMAC and HMAC based control message protection methods. It also supports SIM/USIM cards, digital certificates, and other security based access techniques. Currently very few wireless technologies offer these features.

Full mobility: It is offered through 802.16e standard, on an all IP, packet data based e2e architecture, without any legacy circuit switching. Three methods of hand-offs happen in WiMax networks, viz, hard handoff (HHO), fast base station switching (FBSS), and macro diversity hand over ( MDHO). HHO is nearly offered by all OEMs as mandatory while the other two are optional. In addition, WiMax network can also support air inter-operability which is being coordinated by all the vendors. WiMAx network reference model (NRM) makes it viable for inter-working and roaming with networks that support 3GPP and also wire-line networks of DSL and MSOs. Using common AAA, authentication across WiMax networks globally is made seamless.

IP Compatibility: IP compatible WiMax base stations are evolving to provide an open and diversified interface with various technologies, meaning that the existing IP core can be used to support. Since all the other aspects of WiMax are also on the IP roadmap, drastic optimization in terms of processor speed and faster delivery of services and applications are bound to happen. As every service and application is converging on IP, it is already aligned with the rest of the technology developments. In addition, launching services such as VoIP, multi media applications, location based services, interactive gaming, and movies would be technically and financially viable with improved ROI as compared to other technologies; applications such as SMS over IP, multicast and broadcast.

Rapid deployment: WiMax offers various models of mass and rapid deployment options catering to the needs of mixed use patterns. Foremost amongst them are minimum number of radio sites for a required coverage and capacity requirements. Typical wireless network investment in radio access is around 60-80 percent and WiMax provides an alternative approach which gives faster ROI and time to market advantages. However, the customer premise infrastructure is still a challenge in our market, and prospects of improvements are visible in the next 2-5 years. Hybrid business models to address the existing and future requirements obtain a viable approach while deploying WiMax.

Additionally, as we move towards more energy conscious networks, WiMax provides a perfect solution saving the energy consumption of wireless networks. Power consumption and HVAC are two key aspects of energy efficiency that a typical WiMax network would bring in. The technology nearly addresses all requirements of a developing and emerging market to provide a cost effective, secure, scalable, and futuristic network.

The author is Director, Services Tendering& Business Management, Alcatel-Lucent