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Spark Gaps and Ultra Wide Band Data Transmission
Embedded Geek writes: "It sounds like the revenge of Marconi, but Scientific American has a story about the use of spark gap technology for Ultra Wide Band (UWB) data transmission to send data at 100 to 500 Mbps across short distances (five to ten meters). As with every new technology, 'engineers expect these UWB units to be cheaper, smaller and less power-hungry than today's narrowband radio devices,' but there might be some truth to the hype. The secret appears to be the lack of a carrier wave, allowing use of wide swaths of the spectrum for transmission (the few comments I read at the FCC site referenced in the article addressed spectrum allocation)." Read below for a few more links, too.
"The article pitches the technology as a challenger or succesor to Bluetooth and 802.11a. There are several commercial companies investigating the technology (Aetherwire, Multispectral, and others are cited in the article) and Intel has a paper cited in the article. Spin off applications from the components needed to make this technology work might include a GPS style system accurate to one meter and a radar technology that would allow seeing through walls for construction, rescue, and (ahem) law enforcement."
These are supposed to look like noise to anything else transmitting. Since they spread the signal around a LOT of specturm, they are generally just raising the level of background noise.... What happens when enough of these devices get out there, and the noise floor rises to equal Everest?
What, me worry?
Think about it: Short-wave radios fabricated on a chip that are capable of 100-500 Mbits/sec.
t ml
1. Your PDA would be your CPU + Memory
2. You could put your harddrive in your coat pocket.
3. When you walk towards a monitor, you could wirelessly dock to it or the neighboring keyboards/mice.
This is actually an old article, but I honestly believe if Intel gets this right, UWB is going to be HUGE.
Here's another article:
http://zdnet.com.com/2100-1105-840393.h
"Communism is like having one [local] phone company " - Lenny Bruce
Why should it be a problem? Driving a car doesn't pose a health risk, and those sparks go off 3000RPM*V6=18000 times a second. /do/ pose health risks - 30kHz to 300kHz (correct me if I'm wrong) is extremely dangerous to human organs, but is widely used for shortwave radio. Cell phones operate on microwave frequencies, and both of the above transmit 100s of watts and go 100s-1000s of miles; this spark gap goes all of ten feet; I see no health risk unless you touch it...
And our narrowband transmissions
This is just a different method of sharing spectrum among different users. The currently used methods are pretty good. They have been under development for about 100 years. The Rf spectrum is a limited resource. The amount of information that can be transmitted over the spectrum is limited by Shannon's theorem (read his 1949 paper). This limit can't be increased. What UWB does is spreading its information over really wide bandwidth, raising the noise floor for everybody else. If there are enough UWB transmitters around, they will interfere with each other to the point of uselessness. Also, this will f**k up every other user of the Rf spectrum. In addition, with UWB, the spectrum can't be managed by assigning different frequency bands to different entities. Everyone jsut uses all of the spectrum all the time. The strongest transmitter wins. Sounds like this technology has a good chance of being approved in the US...
"Argue with idiots, and you become an idiot." -- Paul Graham
The power level on this is ridiculously silly low. You mentioned 200 watts, well you're off by a factor of 1000 if that's what you were mentioning.. Of course 200 watts at the 2-3 Ghz range would fry you. But 200 milliwatts is absolutely nothing. No effect. No effect on radio, on television, on cell phones, on nothing.
Does no one actually know what a milliwatt is? It is one ten thousandth (1/1000) of a watt. Does everyone know what a watt is? Well it's 1/1000th of the power consumed by your typical microwave. So what do these two multiplied together give?
(1/1000) * (1/1000) = (1/1000000)
One millionth! So unless you have one million of these fucking devices within 10 meters of each other, you're not going to have anything even coming close to the power of your average microwave.
Yes, you MUST forget those PAST technologies for the sake of consumerism, or call it progress. Analog shortwave must be sacrificed for a variety of economics reasons; the Media giants no longer want analog transmission. Never mind it's inherent simplicity and beauty, it is destined to be all DIGITAL; on a chip and mostly undecipherable except by the handful of chip engineers who make it happen. Capacitors and Inductors, Transistors and Valves, given over to algorithms.
how sad a time to be involved in (Electronics) technology, and I am not normally a Luddite.
Send me back to the 40's.