WiMAX Technology

Date: 2015-10-07; view: 369.

Read this text and fill each gap in paragraphs 1, 4, 7 and 9 with a suitable preposition.

a) Skip through the text once more and find the passages where the following ideas are expressed:

¹Although broadband has been available ___ some time, access ___ most people is still limited. ___ the end of 2002, it was estimated that only 46 million subscribers worldwide had broadband access, with only 17% ___ households ___ the USA being connected. Moreover, the problem isn't one of demand, but of supply.

²Worldwide Interoperability of Microwave Access (WiMAX) is a fast-emerging wide-area wireless broadband technology that shows great promise as the last mile solution for delivering high-speed Internet access to the masses. It represents an inexpensive alternative to digital subscriber lines (DSL) and cable broadband access, the installation costs for a wireless infrastructure based on IEEE 802.16 being far less than today's wired solutions, which often require laying cables and ripping up buildings and streets.

³Wireless broadband access is set up like cellular systems, using base stations that service a radius of several miles/kilometres. Base stations do not necessarily have to reside on a tower. More often than not, the base station antenna will be located on a rooftop of a tall building or other elevated structure such as a grain silo or water tower. A customer premise unit, similar to a satellite TV setup, is all it takes to connect the base station to a customer. The signal is then routed via standard Ethernet cable either directly to a single computer, or to an 802.11 hot spot or a wired Ethernet LAN.

⁴The original 802.16 standard operates ___ the 10-66GHz frequency band and requires line-of-sight towers. The 802.16a extension, ratified ___ January 2003, uses a lower frequency ___ 2-11GHz, enabling non-line-of-sight connections. This constitutes a major breakthrough ___ wireless broadband access, allowing operators to connect more customers ___ a single tower and thereby substantially reduce service costs.

⁵The IEEE 802.16-2004 standard subsequently revised and replaced the IEEE 802.16a and 802.16REVd versions. This is designed for fixed-access usage models. This standard may be referred to as fixed wireless because it uses a mounted antenna at the subscriber's site. The antenna is mounted to a roof or mast, similar to a satellite television dish. IEEE 802.16-2004 also addresses indoor installations, in which case it may not be as robust as in outdoor installations.

⁶The IEEE 802.16e standard is an amendment to the 802.16-2004 base specification and targets the mobile market by adding portability and the ability for mobile clients with appropriate adapters to connect directly to a WiMAX network.

⁷___ early 2005, delays ___ the start of certification testing had led ___ concerns that WiMAX might yet struggle to gain market share as a result. ___ that time, expectations were that the first standard for 802.16e to be signed off by the middle ___ the year, for the first commercial 802.16e products to be available ___ 2006 and for the first laptops integrating an Intel WiMAX chipset to appear the following year.

⁸In the event, Intel launched its much-anticipated mobile WiMAX chip in July 2006, promising commercial trials of the chip in Europe by the end of the year. Rosedale 2 is a low-cost system-on-chip that supports IEEE 802.16-2004 and IEEE 802.16e-2005, enabling WiMAX modems for use with fixed or mobile networks. Service providers can therefore choose to immediately deploy a mobile WiMAX network, or alternatively, deploy a fixed WiMAX network now that can be easily and cost-effectively upgraded to a mobile WiMAX network.

⁹By mid-2006, while the planned deployment ___ fixed WiMAX networks ___ selected areas ___ the UK was well advanced, mobile WiMAX was lagging behind ___ development. Many ___ the mobile operators such as Orange and T-Mobile were promoting the rival HSDPA or Super 3G as the technology to bring high-speed, long-range wireless connectivity ___ laptops and handheld devices.

(By Marshall Brain)