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WiMax-802.16
802.16 specification (also known as WiMax), the IEEE is providing a technology platform for developing low-cost radios that can make fixed broadband wireless a reality. WiMax has the potential to provide the ‘last mile’ connection for office building and rural areas to allow them to use the wireless spectrum to access broadband internet.
The new Institute of Electrical and Electronics Engineers 802.16a standard theoretically can support a maximum 50-kilometer connection at frequencies in the 2 and 11 GHz range, with data rates reaching 280 megabits per second per base station. Unlike previous broadband wireless last-mile technologies, it would be standards based, opening the door for lower cost consumer devices and service offerings.
To get the technology off the ground, a coalition of 40 equipment vendors and service providers have formed the Wi-Max Forum to oversee product marketing and interoperability. With silicon expected in the second half of 2004 and interoperable gear shortly after,
802.16 products likely will reach deployment stage in late 2004 into 2005.
WiMax Components:
The core components of a WiMax system are the subscriber station (SS) otherwise known as the CPE and the base station (BS). A BS and one or more SSs can form a cell with a point-to-multipoint (P2MP) structure. On air, the BS controls activity within the cell, including access to the medium by SSes, allocations to achieve quality of service (QoS) and admission to the network based on network security mechanisms.
An 802.16-based system often uses fixed antenna at the subscriber station site. The antenna is mounted to the roof or an eave. Provisions such as adaptive-antenna systems (AAS) and sub-channelization are also supported optionally by the standard for enhanced link budget required for in-door installation. IEEE 802.16e sub-committee is currently working on extension to the standard required for mobility and support for the power limited SS terminals.
A BS typically uses either sectored/directional or omni-directional antennas. A fixed SS typically uses directional antenna while mobile or portable SS usually uses an omni-directional antenna.
Multiple BSes can be configured to form a cellular wireless network. When orthogonal frequency division multiplexing (OFDM) is used, the cell radius can ideally reach up to 30 miles, however this requires a favorable channel environment and only the lowest data rate can be achieved. Practical cell sizes usually have a small radius of around 5 miles or less. The 802.16 standard also can be used in a point-to-point (P2P) or mesh topology, using pairs of directional antennas. This can be used to increase the effective range of the system relative to what can be achieved in P2MP mode
For more information see
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2006 Wireless & Mobile Expo & Conference
June 7-8, 2006, National Trade Centre, Toronto, Canada
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The 2006 Wireless & Mobile Expo and Conference attracts key decision-makers to learn and purchase the latest products and solutions, offered by innovative technology vendors and service providers. Focusing on the latest wireless and mobile technologies and their enterprise applications, the 2006 Wireless & Mobile Expo and Conference will focus on many hot topics, including Wi-Fi, RFID, Wireless Broadband, Mobile Computing, VoIP, WiMax, Wireless Security, Mobile Devices and many others.
To qualify for FREE Passes, please contact 1-416-292-0038 ext. 821 or visit:
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