Less than one out of five people of the developed world and an even smaller, little percentage of people across the world have broadband access today. Existing technologies such as Digital Subscriber Line (DSL), cable, and fixed wireless are overwhelmed by expensive installs, problems with loop lengths, upstream upgrade issues, line-of-sight restrictions, and poor scalability.

Wimax (802.16) is the next stage to a broadband as well as a wireless world, extending broadband wireless access to new locations and over longer distances, as well as considerably reducing the cost of bringing broadband to new areas. Wimax (802.16) technology offers greater range and bandwidth than the other available or forthcoming broadband wireless technologies such as Wireless Fidelity (Wi-Fi) and Ultra-wideband (UWB) family of standards. It provides a wireless alternative to wired backhaul and last mile deployments that use Data Over Cable Service Interface Specification (DOGS1S) cable modems, Digital Subscriber Line technologies (DSL), T-carrier and E-carrier (Tx/Ex) systems, and Optical Carrier Level (OC-x) technologies. (Jiffy Networks, 2006)
The general initiative of metropolitan area wireless networking, as envisioned with 802.16, begins with what is called fixed wireless. A backbone of base stations is connected to a public network, and each base station carries hundreds of fixed subscriber stations, which can be both public hot spots and fire-walled enterprise networks. Later in the development cycle of 802.16e, Wimax (802.16) is expected to encourage mobile wireless technology specifically wireless transmissions directly to mobile end users, This will be similar in function to the General Packet Radio Service (GPRS) and the one times Radio Transmission Technology (RTT) offered by mobile phone companies.
New organizations as well as individuals are increasingly adopting broadband, whereas those already using broadband are becoming dependent on it and are demanding better services with added benefits. To support this exceptional new demand, Wimax (802.16) has emerged as a feasible solution, because of its inherent features that holds great promise for the future of wireless communications. (Teri Robinson, 2005)
There has been a lot of excitement about Wimax (802.16) and the impact that this standards based wireless network technology will have on the broadband access market. All this hype has generated great expectations, and the industry has responded with exceptional aggression and commitment toward taking broadband to the next level with Wimax (802.16).
How WiMAX Works The backhaul of the Wimax (802.16) is based on the typical connection to the public wireless networks by using optical fibre, microwave link, cable or any other high speed connectivity. In few cases such as mesh networks, Point-to-Multi-Point (PMP) connectivity is also used as a backhaul. Ideally, Wimax (802.16) should use Point-to-Point antennas as a backhaul to join subscriber sites to each other and to base stations across long distance.
A wimax base station serves subscriber stations using Non-Line-of-Sight (NLOS) or LOS Point-to-Multi-Point connectivity; and this connection is referred to as the last mile communication. Ideally, Wimax (802.16) should use NLOS Point-to-Multi-Point antennas to connect residential or business subscribers to the Wimax Base Station (BS). A Subscriber Station (Wimax CPE) typically serves a building using wired or wireless LAN. (Steven J. Vaughan-Nichols, June 2004) |
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