WiMAX, the Worldwide Interoperability for Microwave Access, is a telecommunications technology that provides for the wireless transmission of data in a variety of ways, ranging from point-to-point links to full mobile cellular-type access. The technology is based on the IEEE 802.16 standard (also called WirelessMAN). The name "WiMAX" was created by the WiMAX Forum, which was formed in June 2001 to promote conformity and interoperability of the standard. The forum describes WiMAX as "a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL"[1] (and also to High Speed Packet Access).[citation needed]

Currently, Pakistan has the largest fully functional Wimax network in the world.[2] Wateen Telecom installed the network (with an initial rollout in seventeen cities) throughout Pakistan using Motorola hardware.

Definitions :

The terms "fixed WiMAX", "mobile WiMAX", "802.16d" and "802.16e" are frequently used incorrectly.[4] Correct definitions are the following:
802.16-2004 is often called 802.16d, since that was the working party that developed the standard. It is also frequently referred to as "fixed WiMAX" since it has no support for mobility.
802.16e-2005 is an amendment to 802.16-2004 and is often referred to in shortened form as 802.16e. It introduced support for mobility, amongst other things and is therefore also known as "mobile WiMAX


The bandwidth and range of WiMAX make it suitable for the following potential applications:

Connecting Wi-Fi hotspots with other parts of the Internet.
Providing a wireless alternative to cable and DSL for "last mile" broadband access.
Providing data and telecommunications services.
Providing a source of Internet connectivity as part of a business continuity plan. That is, if a business has a fixed and a wireless Internet connection, especially from unrelated providers, they are unlikely to be affected by the same service outage.
Providing portable connectivity.

Broadband access

Many companies are closely examining WiMAX for last mile connectivity. The resulting competition may bring lower pricing for both home and business customers or bring broadband access to places where it has been economically unavailable.

WiMAX access was used to assist with communications in Aceh, Indonesia, after the tsunami in December 2004. All communication infrastructure in the area, other than Ham Radio, was destroyed, making the survivors unable to communicate with people outside the disaster area and vice versa. WiMAX provided broadband access that helped regenerate communication to and from Aceh.

Subscriber units :

WiMAX subscriber units are available in both indoor and outdoor versions from several manufacturers. Self-install indoor units are convenient, but radio losses mean that the subscriber must be significantly closer to the WiMAX base station than with professionally-installed external units. As such, indoor-installed units require a much higher infrastructure investment as well as operational cost (site lease, backhaul, maintenance) due to the high number of base stations required to cover a given area. Indoor units are comparable in size to a cable modem or DSL modem. Outdoor units are roughly the size of a laptop PC, and their installation is comparable to a residential satellite dish.

With the potential of mobile WiMAX, there is an increasing focus on portable units. This includes handsets (similar to cellular smartphones) and PC peripherals (PC Cards or USB dongles). In addition, there is much emphasis from operators on consumer electronics devices (game terminals, MP3 players and the like); it is notable this is more similar to Wi-Fi than 3G cellular technologies.

Current certified devices can found at the WiMAX Forum web site. This is not a complete list of devices available as certified modules are embedded into laptops, MIDs (Mobile Internet Devices), and private labeled devices

Technical information

WiMAX is a term coined to describe standard, interoperable implementations of IEEE 802.16 wireless networks, similar to the way the term Wi-Fi is used for interoperable implementations of the IEEE 802.11 Wireless LAN standard. However, WiMAX is very different from Wi-Fi in the way it works.

Comparison with Wi-Fi

Comparisons and confusion between WiMAX and Wi-Fi are frequent, possibly because both begin with the same two letters, are based upon IEEE standards beginning with "802.", and are related to wireless connectivity and Internet access. However, the two standards are aimed at different applications.

WiMAX is a long-range system, covering many kilometers that typically uses licensed spectrum (although it is possible to use unlicensed spectrum) to deliver a point-to-point connection to the Internet from an ISP to an end user. Different 802.16 standards provide different types of access, from mobile (similar to a cellphone) to fixed (an alternative to wired access, where the end user's wireless termination point is fixed in location.)
Wi-Fi is a shorter range system, typically tens of meters, that uses unlicensed spectrum to provide access to a network. Typically Wi-Fi is used by an end user to access their own network, which may or may not be connected to the Internet. If WiMAX provides services analogous to a cellphone, Wi-Fi is similar to a cordless phone. It's important to note, however, that free community Wi-Fi networks have shown that, with proper antennas, Wi-Fi can have a very long range.[citation needed]
WiMAX and Wi-Fi have quite different Quality of Service (QoS) mechanisms. WiMAX uses a mechanism based on connections between the Base Station and the user device. Each connection is based on specific scheduling algorithms, which means that QoS parameters can be guaranteed for each flow. Wi-Fi has introduced a QoS mechanism similar to fixed Ethernet, where packets can receive different priorities based on their tags. This means that QoS is relative between packets/flows, as opposed to guaranteed.
WiMAX is highly scalable from what are called "femto"-scale remote stations to multi-sector 'maxi' scale base that handle complex tasks of management and mobile handoff functions and include MIMO-AAS smart antenna subsystems.
Due to the ease and low cost with which Wi-Fi can be deployed, it is sometimes used to provide Internet access to third parties within a single room or building available to the provider, often informally, and sometimes as part of a business relationship. For example, many coffee shops, hotels, and transportation hubs contain Wi-Fi access points providing access to the Internet for customers

Mobile Broadband Wireless Access

Mobile Broadband Wireless Access (MBWA) is a technology being developed by IEEE 802.20 and is aimed at wireless mobile broadband for operations from 120 to 350 km/h. The 802.20 standard committee was first to define many of the methods which were later funneled into Mobile WiMAX, including high speed dynamic modulation and similar scalable OFDMA capabilities. It apparently retains fast hand-off, Forward Error Correction (FEC) and cell edge enhancements.

The Working Group was temporarily suspended in mid 2006 by the IEEE-SA Standards Board since it had been the subject of a number of appeals, and a preliminary investigation of one of these "revealed a lack of transparency, possible 'dominance,' and other irregularities in the Working Group".[21]

In September 2006 the IEEE-SA Standards Board approved a plan to enable the working group to continue under new conditions, and the standard is now expected to be finalized by Q2 2008.

Future development

Mobile WiMAX based upon 802.16e-2005 has been accepted as IP-OFDMA for inclusion as the sixth wireless link system under IMT-2000. This can hasten acceptance by regulatory authorities and operators for use in cellular spectrum. WiMAX II, 802.16m will be proposed for IMT-Advanced 4G.

The goal for the long term evolution of both WiMAX and LTE is to achieve 100 Mbit/s mobile and 1 Gbit/s fixed-nomadic bandwidth as set by ITU for 4G NGMN (Next Generation Mobile Network) systems through the adaptive use of MIMO-AAS and smart, granular network topologies. 3GPP LTE and WiMAX-m are concentrating much effort on MIMO-AAS, mobile multi-hop relay networking and related developments needed to deliver 10X and higher Co-Channel reuse multiples.

Since the evolution of core air-link technologies has approached the practical limits imposed by Shannon's Theorem, the evolution of wireless has embarked on pursuit of the 3X to 10X+ greater bandwidth and network efficiency by advances in the spatial and smart wireless broadband networking technologies.

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