WiMAX

The WiMAX Forum was formed in June 2001 to promote conformity and interoperability, including the definition of system profiles for commercial vendors.

[1] 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".

WiMAX was sometimes referred to as "Wi-Fi on steroids"[5] and can be used for a number of applications including broadband connections, cellular backhaul, hotspots, etc.

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.

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.

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 hoped to benefit from combined services offerings and network resources as a springboard past its competitors.

Some wireless industry analysts, such as Ken Dulaney and Todd Kort at Gartner, were skeptical how the deal would work out: Although fixed-mobile convergence had been a recognized factor in the industry, prior attempts to form partnerships among wireless and cable companies had generally failed to lead to significant benefits for the participants.

Other analysts at IDC favored the deal, pointing out that as wireless progresses to higher bandwidth, it inevitably competes more directly with cable, DSL and fiber, inspiring competitors into collaboration.

WiMAX gateway devices are available as both indoor and outdoor versions from manufacturers including Vecima Networks, Alvarion, Airspan, ZyXEL, Huawei, and Motorola.

Such devices typically sit near the customer's window with the best signal, and provide: 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.

The device, made available on June 4, 2010,[15] is capable of both EV-DO(3G) and WiMAX(pre-4G) as well as simultaneous data & voice sessions.

The original version of the standard on which WiMAX is based (IEEE 802.16) specified a physical layer operating in the 10 to 66 GHz range.

(See WiMAX MIMO) This brings potential benefits in terms of coverage, self installation, power consumption, frequency re-use and bandwidth efficiency.

[19] The WiMAX MAC uses a scheduling algorithm for which the subscriber station needs to compete only once for initial entry into the network.

As a standard intended to satisfy needs of next-generation data networks (4G), WiMAX is distinguished by its dynamic burst algorithm modulation adaptive to the physical environment the RF signal travels through.

Burst profiles are used inverse (algorithmically dynamic) to low signal attenuation; meaning throughput between clients and the base station is determined largely by distance.

Analog TV bands (700 MHz) may become available, but await the complete digital television transition, and other uses have been suggested for that spectrum.

EU commissioner Viviane Reding has suggested re-allocation of 500–800 MHz spectrum for wireless communication, including WiMAX.

Since October 2007, the Radio communication Sector of the International Telecommunication Union (ITU-R) has decided to include WiMAX technology in the IMT-2000 set of standards.

[27] This enables spectrum owners (specifically in the 2.5–2.69 GHz band at this stage) to use WiMAX equipment in any country that recognizes the IMT-2000.

Operating at the maximum range of 50 km (31 mi) increases bit error rate and thus results in a much lower bitrate.

However, with adequate capacity planning and the use of WiMAX's QoS, a minimum guaranteed throughput for each subscriber can be put in place.

A number of specialized companies produced baseband ICs and integrated RFICs for WiMAX Subscriber Stations in the 2.3, 2.5 and 3.5 GHz bands (refer to 'Spectrum allocation' above).

This enables the user to place the WiMAX Subscriber Unit in the best reception area, such as a window, and have date access throughout their property.

[31] Those that pass conformance and interoperability testing achieve the "WiMAX Forum Certified" designation, and can display this mark on their products and marketing materials.

[32] In 2011, the Telecommunications Industry Association released three technical standards (TIA-1164, TIA-1143, and TIA-1140) that cover the air interface and core networking aspects of Wi-Max High-Rate Packet Data (HRPD) systems using a Mobile Station/Access Terminal (MS/AT) with a single transmitter.

In the future, competition will be from the evolution of the major cellular standards to 4G, high-bandwidth, low-latency, all-IP networks with voice services built on top.

Among many enhancements, IEEE 802.16m systems can provide four times faster[clarification needed] data speed than the WiMAX Release 1.

[41] Worldwide, by early 2010 WiMAX seemed to be ramping quickly relative to other available technologies, though access in North America lagged.

WiMAX base station equipment with a sector antenna and wireless modem on top
A WiMAX USB modem for mobile access to the Internet
Airstream 1200 USB Modem
The WiMAX Forum architecture
Picture of a WiMAX MIMO board
WiSOA logo
Speed vs. mobility of wireless systems: Wi-Fi , High Speed Packet Access (HSPA), Universal Mobile Telecommunications System (UMTS), GSM