802.16 or WiMAX which stands for Wi (WiFi) Microwave Access (MA) is an evolution of today's wifi technology using similar coding techniques including OFDM (Orthogonal Frequency Division Multiplexing). The step change is that WiMAX allows many channels to be run close to each other enabling greater data throughput. The other major difference is that WiMAX is likely to run on licensed spectrum rather than the free for all that is 802.11, the advantage here is that the greater number of channels reduces the need for re use and so the signals can be allowed to travel much further.

How far? well it's a little known fact that bog standard 802.11 can travel many miles (the world record is 125 miles) but it is the practical application that determines useable distance which largely confines wifi to a small area or hotspot. WiMAX with it's many channels and use of licensed spectrum can be used to great effect in a metropolitan area where it is most likely to be used for last mile internet access, finding a way round the cable and telecoms providers and providing high speed low cost internet to consumers.

There have been many rumours of streetlamp becoming WiFi masts and perhaps WiMAX is the technology to make this happen. These kinds of application are likely to be in the 10 - 66Ghz range allowing a reliable service to be built on licensed spectrum. The concept of base stations a bit like mobile phone networks serving a local or metropolitan area has already been proposed and the theoretical limit of 50 km (or 31 miles) certainly has service providers excited.

An extension of the standard is still under discussion this 802.16e standard is for devices under 10Ghz and those that may also operate in unlicensed spectrum, here interoperability becomes and issue as does interference. This mobile standard is also essential for fast hand off, this is something we've all become very used to with mobile networks both 2 and 3G, the device can quickly switch between base stations enabling the connection to be maintained seamless to the user.

The mobile standard is likely to be ratified and used by chip makers like Intel in 2007, but WiMAX is already making an appearance in the UK, while some train companies were using satellite to provide backbone services to their fleet so that passengers can use their laptops during journeys, one company is using WiMAX.

Southern Trains' Brighton Express is the first UK service to use WiMAX to backhaul fast internet to its fleet, dispensing with the satellite systems its provider T-Mobile used to offer. At present the project is only viable because of T-Mobiles backing as the WiMAX equipment isn't cheap but that will change as the big boys get behind the standard.

manufacturers who try to implement WiMAX into portable products like laptops, PDA's and even Smartphones will undoubtedly face challenges in power consumption but the prize seems worth fighting for. There is a bit of spin here, ask a Telco what WiMAX is for and they very quickly say it compliments 3G as a data only broadband data stream, ask a non Telco and VOIP appears, it's a bit like asking turkeys to vote for Christmas!

But Christmas is coming and WiMAX looks like it might finally deliver that truly mobile broadband service that many users including everyone at Lordpercy.com would gladly pay for.

Published - 07/08/2005

More Technology Explained-

[ Up ] [ Firewalls Explained ] [ HDTV Explained ] [ DAB Digital Radio ] [ How to Bluejack ] [ RFID Explained ] [ Gadgets 2004 ] [ GPS Explained ] [ Bluetooth Explained ] [ WiFi Explained ] [ Gadgets 2005 ] [ Gadgets 2007 ] [ Broadband Explained ] [ Next Fest 2005 ] [ Gadgets 2006 ] [ Podcasting Explained ] [ WiMAX Explained ] [ GPRS Technology Explained ] [ Search Engines ] [ Speed Cameras Explained ] [ CeBit 2004 ]