The Battle for High-speed Wireless Supremacy

Many factors are responsible for the success or failure of any technology that go far beyond its technical superiority. More often than not, these have to do with how many companies accept its potential, are convinced of it, and are willing to back it up. They push the case for its ratification with standardization bodies. So essentially, the survival of any technology depends upon how well it adapts to the environment, such that it tilts the relevant audience in its favor instead of the other competing technologies. Interestingly, this looks similar to Darwin's theory of Natural Selection; only that living organisms have been replaced by competing technologies! This prelude was necessary to set the context of this article right, as this time it doesn't have to do with technical 

supremacy alone. The technology in question is for enabling high-speed wireless multimedia communication, and there are three contenders vying for this space. These include IEEE's high-speed WLAN standard called 802.11n, and two competing standards for UWB

(UltraWide Band).

High-speed wireless communication holds relevance in both homes and offices. At home, wireless networking is becoming hot, and there's a need not only for wireless data networks, but also for a network that can connect home appliances like, TV, home theatre system, set-top box, DSL connection and so on. In offices, there's always been a need for higher bandwidth, be it for higher throughput or for time-sensitive applications like VoIP. Both of these will be possible only if the wireless standards support higher throughputs.

Let's take 802.11n and UWB first. Interestingly, while the former is a WLAN technology, the latter caters to WPANs or wireless personal area networks. They're not supposed to compete, but that is exactly what's happening. 802.11n is being designed to work with consumer electronics, personal computing, as well as handheld devices. It's the next step to the earlier a, b and g standards and, therefore, uses the same frequency bands for operation. The long and short of it is that throughput has to be increased keeping the frequency band constant. One way of achieving this is through MIMO, multiple input multiple output, wherein multiple antennae are used to send multiple data streams in parallel across the wireless channel. As one can imagine, this increases the circuit complexity as well as the power requirements. 

UWB, on the other hand, uses a much wider band for data transmission and reception, and requires far lesser power. In fact, one variation of UWB, namely the DS-UWB (Direct Sequence) consumes 500 times lesser power. So whenever products based on UWB appear, they should be cheaper than 802.11n based products. The problem is that the reality is a little different. Many MIMO-based products have already been launched in the market before the ratification of 802.11n. On the consumer electronics side, 802.11 a- , b- and g-based products are already available that allow you to connect your TV or home theatre system to your PC wirelessly. So 802.11n will already have a base of previously proven products to stand upon, while UWB will have to start afresh. 

Even before UWB starts competing with 802.11n, it has to win over its internal battles. That's where the non-technology part that I'd mentioned earlier comes into play. Currently, there are two competing standards for the same technology, each backed by a different group. One is the WiMedia Alliance, backed by companies like Intel, Sony, Microsoft and HP, while the other is UWB forum, being funded by Motorola and Free Scale. The former pushes a UWB technology known as Orthogonal Frequency Division Multiplexing-UWB, while the latter pushes DS-UWB we just talked of. The former promises throughputs of up to 480 Mbps over 2 to 4 meters, with plans to go up to 1 Gbps, while the latter claims that their technology can scale from 100 Mbps to 2 Gbps in a similar range. It's difficult to say which is the better one, so each side is just trying to muster up as much support as it can from international standards bodies. The latest feather in the cap of WiMedia is Ecma International, the European standards body.

So currently at least, WiMedia seems to have a lead over the UWB forum. But then you never know which way the tables may turn. If each side manages to introduce products based on their respective standards, then the market will see a jumble of devices that are incompatible with each other. The possibility of putting both the technologies on the same chip has been ruled out, because the economics doesn't work out for it. It apparently doubles the size of the chip, which then becomes quite expensive to manufacture. 

Another interesting thing is that Intel is also backing up the 802.11n standard. So will it allow the technology to compete with UWB? That remains to be seen, because Intel plans to use UWB for its wireless USB standard. So for now, it looks as if the 802.11n standard has a lead over

UWB.

Anil Chopra, Associate Editor