Type of 
wireless technology that provides wireless internet service over longer distances than standard Wi-Fi. WiMax is based on standard IEEE 802.16 technology and can provide broadband wireless access up to 30 miles. WiMax uses fixed and mobile stations to provide users with access to high-speed voice, data, and Internet connectivity. WiMax technology has not been widely accepted by the technology community, but its popularity continues to grow as businesses and consumers seek out better ways to constantly stay connected.
wireless technology that provides wireless internet service over longer distances than standard Wi-Fi. WiMax is based on standard IEEE 802.16 technology and can provide broadband wireless access up to 30 miles. WiMax uses fixed and mobile stations to provide users with access to high-speed voice, data, and Internet connectivity. WiMax technology has not been widely accepted by the technology community, but its popularity continues to grow as businesses and consumers seek out better ways to constantly stay connected.Terminology[edit]
WiMAX refers to interoperable implementations of the IEEE 802.16 family of wireless-networks standards ratified by the WiMAX Forum. (Similarly, Wi-Fi, refers to interoperable implementations of the IEEE 802.11 Wireless LAN standards certified by the Wi-Fi Alliance.) WiMAX Forum certification allows vendors to sell fixed or mobile products as WiMAX certified, thus ensuring a level of interoperability with other certified products, as long as they fit the same profile.
The original IEEE 802.16 standard (now called "Fixed WiMAX") was published in 2001. WiMAX adopted some of its technology from WiBro, a service marketed in Korea.[3]
Mobile WiMAX (originally based on 802.16e-2005) is the revision that was deployed in many countries, and basis of future revisions such as 802.16m-2011.
WiMAX is sometimes referred to as "Wi-Fi on steroids"[4] and can be used for a number of applications including broadband connections, cellular backhaul, hotspots, etc. It is similar to Wi-Fi, but it can enable usage at much greater distances.[5]
Uses[edit]
The bandwidth and range of WiMAX make it suitable for the following potential applications:
- Providing portable mobile broadband connectivity across cities and countries through a variety of devices.
- Providing a wireless alternative to cable and digital subscriber line (DSL) for "last mile" broadband access.
- Providing data, telecommunications (VoIP) and IPTV services (triple play).
- Providing a source of Internet connectivity as part of a business continuity plan.
- Smart grids and metering
Internet access[edit]
WiMAX can provide at-home or mobile Internet access across whole cities or countries. In many cases this has resulted in competition in markets which typically only had access through an existing incumbent DSL (or similar) operator.
Additionally, given the relatively low costs associated with the deployment of a WiMAX network (in comparison with 3G, HSDPA, xDSL, HFC or FTTx), it is now economically viable to provide last-mile broadband Internet access in remote locations.
Middle-mile backhaul to fibre networks[edit]
Mobile WiMAX was a replacement candidate for cellular phone technologies such as GSM and CDMA, or can be used as an overlay to increase capacity. Fixed WiMAX is also considered as a wireless backhaul technology for 2G, 3G, and 4G networks in both developed and developing nations.[6][7]
In North America, backhaul for urban operations is typically provided via one or more copper wire line connections, whereas remote cellular operations are sometimes backhauled via satellite. In other regions, urban and rural backhaul is usually provided by microwave links. (The exception to this is where the network is operated by an incumbent with ready access to the copper network.) WiMAX has more substantial backhaul bandwidth requirements than legacy cellular applications. Consequently the use of wireless microwave backhaul is on the rise in North America and existing microwave backhaul links in all regions are being upgraded.[8] Capacities of between 34 Mbit/s and 1 Gbit/s [9] are routinely being deployed with latencies in the order of 1 ms.
In many cases, operators are aggregating sites using wireless technology and then presenting traffic on to fiber networks where convenient. WiMAX in this application competes with microwave, E-line and simple extension of the fiber network itself.
Triple-play[edit]
WiMAX directly supports the technologies that make triple-play service offerings possible (such as Quality of Service and Multicasting). These are inherent to the WiMAX standard rather than being added on as Carrier Ethernet is to Ethernet.
On May 7, 2008 in the United States, Sprint Nextel, Google, Intel, Comcast, Bright House, and Time Warner announced a pooling of an average of 120 MHz of spectrum and merged with Clearwire to market the service. The new company hopes to benefit from combined services offerings and network resources as a springboard past its competitors. The cable companies will provide media services to other partners while gaining access to the wireless network as aMobile virtual network operator to provide triple-play services.
Some analysts[who?] questioned how the deal will work out: Although fixed-mobile convergence has been a recognized factor in the industry, prior attempts to form partnerships among wireless and cable companies have generally failed to lead to significant benefits to the participants. Other analysts point out that as wireless progresses to higher bandwidth, it inevitably competes more directly with cable and DSL, inspiring competitors into collaboration. Also, as wireless broadband networks grow denser and usage habits shift, the need for increased backhaul and media service will accelerate, therefore the opportunity to leverage cable assets is expected to increase.
Deployment[edit]
- WiMAX access was used to assist with communications[citation needed] in Aceh, Indonesia, after the tsunami in December 2004. All communication infrastructure in the area, other than amateur radio, was destroyed[citation needed], 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.[citation needed]
- WiMAX hardware was donated by Intel Corporation to assist the Federal Communications Commission (FCC) and FEMA in their communications efforts in the areas affected by Hurricane Katrina.[10] In practice, volunteers used mainly self-healing mesh, Voice over Internet Protocol (VoIP), and a satellite uplink combined with Wi-Fi on the local link.[11]
Connecting[edit]
Portable units include handsets (similar to cellular smartphones); PC peripherals (PC Cards or USB dongles); and embedded devices in laptops, which are now available for Wi-Fi services. In addition, there is much emphasis by operators on consumer electronics devices such as Gaming consoles, MP3 players and similar devices. WiMAX is more similar to Wi-Fi than to other 3G cellular technologies.
The WiMAX Forum website provides a list of certified devices. However, this is not a complete list of devices available as certified modules are embedded into laptops, MIDs (Mobile Internet devices), and other private labeled devices.
Gateways[edit]
WiMAX gateway devices are available as both indoor and outdoor versions from several manufacturers including Vecima Networks, Alvarion, Airspan, ZyXEL,Huawei, and Motorola. The list of deployed WiMAX networks and WiMAX Forum membership list [1] provide more links to specific vendors, products and installations. The list of vendors and networks is not comprehensive and is not intended as an endorsement of these companies above others.
Many of the WiMAX gateways that are offered by manufactures such as these are stand-alone self-install indoor units. Such devices typically sit near the customer's window with the best signal, and provide:
- An integrated Wi-Fi access point to provide the WiMAX Internet connectivity to multiple devices throughout the home or business.
- Ethernet ports to connect directly to a computer, router, printer or DVR on a local wired network.
- One or two analog telephone jacks to connect a land-line phone and take advantage of VoIP.
Indoor gateways are convenient, but radio losses mean that the subscriber may need to be significantly closer to the WiMAX base station than with professionally installed external units.
Outdoor units are roughly the size of a laptop PC, and their installation is comparable to the installation of a residential satellite dish. A higher-gain directional outdoor unit will generally result in greatly increased range and throughput but with the obvious loss of practical mobility of the unit.
External modems[edit]
USB can provide connectivity to a WiMAX network through what is called a dongle.[12] Generally these devices are connected to a notebook or net book computer. Dongles typically have omnidirectional antennas which are of lower gain compared to other devices, as such these devices are best used in areas of good coverage.
Mobile phones[edit]
HTC announced the first WiMAX enabled mobile phone, the Max 4G, on November 12, 2008.[13] The device was only available to certain markets in Russia on the Yota network.
HTC and Sprint Nextel released the second WiMAX enabled mobile phone, the EVO 4G, March 23, 2010 at the CTIA conference in Las Vegas. The device, made available on June 4, 2010,[14] is capable of both EV-DO(3G) and WiMAX(4G) as well as simultaneous data & voice sessions. Sprint Nextel announced at CES 2012 that it will no longer be offering devices using the WiMAX technology due to financial circumstances, instead, along with its network partnerClearwire, Sprint Nextel will roll out a 4G network deciding to shift and utilize LTE 4G technology instead.
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