Mobile WIMAX

Mobile WiMAX

WiMAX is still to happen in a big way in India and already a new mobile version of the same is ready. Here, we look at this new avatar and the product line-ups expected around it next year

Saturday, November 04, 2006

Sometime last December, mobile WiMAX was made formally possible with the IEEE ratifying the 802.16e standard. There are two specifications, one called the 802.16-2004 or 802.16d and the other being 802.16-2005 or the 802.16e. The first spec involves WiMAX devices that are fixed, while the 2005 spec extends WiMAX capability to mobile devices. 802.16-2004 devices can be upgraded to the 2005 standard via a simple software upgrade. Well, since December 2005, there has been hectic activity in the Mobile WiMAX space and here's a snapshot of the technologies and products that have come out.

New baseband chip

Intel launched a new baseband chip named the WiMAX Connection 2250 as we were going to press. This chip complies with both the 802.16d and 802.16e specifications. This chip can be coupled with the Intel Discreet Tri-band WiMAX radio to get an all-frequency mobile wireless solution that can be used globally. The processor is backward (pin) compatible with the earlier released Intel PRO/Wireless 5116 broadband chip, which uses the 802.16d technology.

This means deployments that have already happened using the 5116 can now be easily upgraded to the new standard. Products based on this chip are expected over the next year. These products are expected to be WiMAX modems and gateways for IP voice, video and data communications.
Mobile WiMAX and 3G European countries are planning to set aside the 3.4 to 3.5 GHz spectrum for WiMAX operations, with the 2.3 to 2.5 GHz band for 3G networks. But, industry analysts are complaining that this is too narrow a band to ensure a drop-free connection.

Also, when you consider that this standard is designed to be used with devices that are on the move, like in cars, trains and so on, there would be a lot of frequency hopping and jamming occurring as users move from one area to another or even roam onto other networks.

The narrow bandwidth of just 0.1 GHz is therefore too small to accommodate such traffic. 3G network operators in the EU use the 2.3 to 2.5 GHz. This spectrum is not used in the USA or Asia and therefore the 3.4-3.5 GHz band battle is not spilling over this region.

Products in 2007
Lots of WiMAX based products are expected to be released over the coming year.

There will be multi-node radios that have a half a mile range and can do live video streaming. Such radios can do 162 Mbps over four wireless links. Then there is a base station line up that can work with both the 2004 and 2005 spec-this means this device operates using both FDM and TDM algorithms and a software-defined radio.

Many vendors are also planning module upgrades and updates that simply enable their existing 802.16d products to support the 802.16e spec as well. What you would need to notice while selecting among this crop of products is whether they support the 2.4-2.5 GHz spectrum or the 3.5 GHz band.

There are also multi-node base stations due, which can do wireless mesh networks as well as WiMAX. This is handled by new versions of system software. WiMAX chip makers have started unveiling their line ups of chipsets for PCI cards, SD/IO cards, USB dongles and CardBus adapters for both the US/Asia and the Europe spectrums.

One product that finds interesting is a 'remote tiltable antenna' from an Irish company. Remote technicians can tilt this antenna (mounted on high-rising towers) to optimize wireless delivery and maintain signal strength.