UWB May Revolutionize Wireless Networking... Someday

We've got 802.11b and Bluetooth SpringBoard modules for the Visor at work. The Bluetooth one fits inside the SpingBoard slot and uses little power - the 802.11b module is huge and needs it's own battery supply, and still runs out of power in an hour or 2. Anyone who knows anything about PDAs knows that size and battery life are really important.

So, it's very important if Ultra Wide Band is low power & small for us PDA users - anyone know anything about it?

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russ@russb.fsnet.co.uk

UWB is potentially even easier to include in a handheld than Bluetooth. There are circuit diagrams that compare Bluetooth and UWB in the Intel article listed under "Related Information".

Sorry, Scientific American does not put the contents of its most recent issue on its website. Nevertheless, I have to cite it as the source of much of this info. You might also take a look at the Intel article.

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News Editor

High data rates... Yes, but it will depend highly on how UWB is used in the network. I don't have the papers handy, but it's something like this: The transmitter will transmit something like 500Mbps, but it uses alot of redundancy to ensure a valid signal. The receiver will take a running sum of the bits recieved. Then it devides it by the number of bit times (takes an average) to determine what the correct signal was. You can be sure there will be errors (plenty of them) and taking the average makes it more probable that the correct signal can be extrapolated. I'll have to dig around and see if I can find those papers. It's really interesting reading.

Tip DS

Secondly, how you FCC rule against such a which use of bandwidth? Even though this is low powered?

Anyone remember Bluetooths rival technology that would used 1/100th the power of Bluetooth?

First, the FCC has US jurisdiction over all intentional and most unintentional radiators of radio energy, regardless of power level. My gosh... if somebody didn't play traffic cop, communications as we know it wouldn't be possible.

UWB is a compelling technology, but implementation will definely be at a measurable cost to other users of RF spectrum. GPS won't be the only victim - anybody else who relies on sniffing weak signals out of the background static (we call it "noise floor") is going to have a tough go of it. UWB raises the noise floor we've already seen it plenty of times in narrower frequency-hopping implementations (Bluetooth and 802.11 included).

Bottom line is that there are millions of users relying on narrow-band technologies who would be adversely affected by UWB. This is especially true in the current climate, where NB users are being asked (told) to reduce power and increasingly rely on weak-signal acquisition methods. We may get to UWB someday, but not without a large impact and likely a long, drawn-out cutover process.

A potential Bluetooth replacement is already on the horizon in the form of ultrawideband (UWB) technology. Recently approved by the Federal Communications Commission (FCC), UWB uses one-thousandth of the power of Bluetooth, an important consideration for small, battery-operated devices. It is also much more secure than current wireless systems. It works by sending pulses so weak that they are virtually undetectable amid the natural radio "noise" that permeates the environment, unless the receiver is keyed to the same pattern used by the particular transmitter.

However, UWB technology is three to five years from market introduction and has yet to receive licensing approval outside the US. While homeland security activities by the US government may spur UWB development, we do not expect it to become a practical technology for at least three years.

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