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FCC on Ultra-Wideband, DSL Services
ibirman writes: "According to Yahoo, the FCC has approved limited use of Ultrawideband (UWB) technology above 3.1 gigahertz. The article states that Sprint PCS among others has been campaigning to keep the minimum above 6 gigahertz claiming "interference". From what I have read, interference is not an issue, so I wonder what their real agenda is? Funny that the article does not mention that UWB could revolutinize high speed wireless networking." There's a Newsbytes story that decribes an upcoming ruling on DSL providers, which would exempt DSL carriers from the open-access requirements in place for most telephone services. There are a few links to statements on the front page of fcc.gov, but I don't see the actual orders for either of these yet.
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It's possible that a UWB system could interfere with these, but your UWB transmitter would have to be very close to your cell phone or TV. It's only been approved for very short distances, so there shouldn't be much risk of interfering with other people's cell phone reception, just that in your own home or office. Still, it's an interesting loophole for people who want to block cell phone signals. ("No officer, this isn't an illegal cell phone jammer, it's a UWB network!")
Larry Fullerton, now of Time Domain, invented a radar and wireless system based on pulses of energy less than a billionth of a second in duration. The scheme is known as ultrawideband. Although ultrawideband pulsed radar has been around for decades, the U.S. Patent and Trademark Office decided in 1987 that Fullerton's system was original enough to be patented.
In the early 1990s, however, Thomas E. McEwan, then an employee at the Livermore lab, came up with a related idea for a "micropower impulse radar" that employed different circuitry and worked at much lower power. His device can function for years on a couple of penlight batteries, he states. He got patents, too, and assigned them to his employer, which started licensing the invention to manufacturers. But McEwan failed to cite Fullerton's invention as "prior art" in his original patent application.
Sprint backed the wrong horse and spent millions in licensing fees to Livermore lab. Their opposition to UWB is pure vindictiveness.
Now Time Domain refuses to license UWB to sprint, putting them at an extreme disadvantage to ATT and other competitors.
Beautiful technology though... this is one of those real "could change the world" technologies like the step from Analog to Digital signaling
If voting were effective, it would be illegal by now.
In reading the story at yahoo, I found the following quote:
However, companies like mobile telephone service provider Sprint PCS and the powerful lobbying arm of the airline industry, among others, had urged the FCC to prohibit the use of UWB technologies below 6 gigahertz.
Now, I can certainly understand how a mobile phone service provider such as Sprint could have less-than-credible reasons for not wanting to move forward with this initiative... However, I do not understand what the airline industries motivation would be to get involved here except for a genuine concern for unsafe interference.
Personally, I could careless if my cell phone has a little bit of static as a result of leveraging UWB, but if my plane crashes due to interence then I may not be quite so understanding...
Then again, perhaps I am missing something obvious. Anyone have any thoughts on what ulterior motives the airline industry may have here?
Beer is proof that God loves us and wants us to be happy. -- Benjamin Franklin
This is going to make radio astronomy more difficult. There are several spectral lines that lie between 3 and 10 GHz (I'm assuming that 10 is somewhere near the upper limit). As if light pollution and Iridium satellites weren't bad enough for visual astronomy, now radio astronomers are going to have to deal with elevated noise levels in a few interesting lines.
It looks like business wins out over the quest for knowledge once again.
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I didn't want to leave this space blank.
"Should the FCC reclassify digital subscriber lines (DSL) as an information service as opposed to a traditional wire-line service, it could effectively loosen federal rules that require Bell companies and other incumbent carriers to offer their competitors equal access to the telecommunications networks they control."
What the hell? After the Bells displayed their ability to cut of CLECs like they were batting down baby seals within the existing rules?
What world is the FCC living in?
There are many users of the RF spectrum that don't fall into the category of "evil corporation". As an amateur radio licensee, I'm very concerned that widespread and unregulated use of UWB technology would further pollute the amateur radio bands with noise and interference. Cheaply made consumer electronics equipment, light dimmers, poorly maintained power lines and other "unintentional radiators" are a major source of interference in many places. That includes all of you people who run your computer with the case open.
Mea navis aericumbens anguillis abundat
had a story about this on Morning Edition this morning.
a m
Here's the audio file of the segment:
http://www.npr.org/ramfiles/me/20020214.me.07.r
A commentator on there seemed to think it would interfere with all sorts of things acting like a "layer of jelly" which the poor little GPS device could not operate through.
Most people would die sooner than think; in fact, they do.
First, comparing the two systems' measurement accuracy is apples and oranges. UWB might be usable as a point-to-point ranging source, sort of like a stud finder, but it only tells you how far a given object is from, say, your handheld transmitter. GPS, on the other hand, gives you a three-dimensional position fix anywhere on earth (as long as you can see a reasonable patch of the sky). The two are simply not measuring the same thing. (Furthermore, a properly set up variant of GPS called a "differential" setup can deliver accuracy of better that 1cm.)
Second, UWB is not necessarily as low-power a system as is claimed in the article. Typical UWB transmitter power levels are around 1 milliwatt (typical cell phones are around 1 watt), which is ten times higher than what Cringely claims. (The idea is that because the energy is spread across a wide swath of frequencies, the power in any one band is relatively low.) Furthermore, UWB power levels are strongly dependent on the desired distance between transmitter and receiver.
Third, applications are currently being developed for using GPS and its variants indoors.
Finally, UWB can pose problems for GPS. The nominal GPS signal is, by design, about 15dB below the ambient noise floor -- that is, it's about 30 times quieter than the static you'd receive if you tuned a radio between stations. Thus GPS can be particularly sensitive to even very low-level intereference. I work in a GPS Lab and we have been examining the potential UWB-GPS interference issues for about the past two years. The point is, this is a big deal because GPS will likely be used in a number of safety-critical applications (e.g. landing airplanes) within the next 5-10 years. Dismissing the potential objections to UWB out of hand is therefore not only ill-advised, but potentially dangerous.
The list of publications on the lab's main page includes papers with detailed explanations of the points I've made above.
-FP
In last week's EETimes, there was a good intro to UWB and its challenges, as well as a discussion about the (considerable) importance of the FCC ruling that just took place (in a front page story). The Web versions are:
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