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.

Comments

Considerable concern

[sphealey]

In fact, there is considerable concern in the GPS and radionavigation worlds that UWB may cause severe interference with pre-existing services - many of which are directly related to life saftey. Tests sponsored by the UWB industy to prove that such interference would not occur showed the exact opposite - that it did in fact occur. I am surprised that the FCC gave the go-ahead on this.

sPh

Re:Considerable concern

[Kurayamino-X]

has anyone pointed out there in the process of launching a new, more powerfull, more accurate GPS system to replace the one currently in opperation? just because some decade old technology doesent work with UWB interferance doesent mean the new system will. course, if it doesent, then theyve just wasted there money on a new, useless GPS... (i think this was posted on slashdot. coulda just been in new scientist or summin) and hell, the third generation of GPS will prolly work on a UWB pulsed radar system anyhow. and the US military seems to like UWB pulsed radar. seeing as they've made a few "look through this here wall" devices and a more accurate then current GPS can hope to be tracking system using UWB. (this was in a slashdot post about half a year ago... linked to fullertons homepage too.) UWB has more uses then just damn fast wireless networking.

Okay for very short distances

[cyberformer]

A filter can remove the UWB signal from the (relatively narrow) bands used for GPS. This still leaves a lot of bandwidth, which is currently used by cell phones, TV stations, etc.

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!")

Re:Okay for very short distances

[sphealey]

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.

Until 10-20k UWB devices are installed in an office park next to the airport.

Also, the signal strength as received by a GPS unit is incredibly low - very close to undetectable. It doesn't take much to disrupt them. In fact a month or so ago there was a NOTAM for a GPS outage in Phoenix AZ over a three day period. No reason was given but it is assumed that a new satellite was being tested at Motorola's satellite assembly facility - enough to shut down GPS in the entire county.

Here's a more complete article: GPS World.

sPh

pure vindictiveness

[Perdo]

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

PCS has 4.2 to 6GHz...

[MattRog]

According to my frequency allocation chart, the 4.2 to 6GHz band is reserved (dually with some other things) for 'Experimental PCS'. Perhaps they're worried about people running amok in 'their' band?

Wait one minute...

[NOT-2-QUICK]

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?

Re:Wait one minute...

[sphealey]

Anyone have any thoughts on what ulterior motives the airline industry may have here?

It's not really "ulterior". Airline traffic today flows, for the most part, along the Federal Airways layed out in the 1920's for airmail pilots to follow. These consisted of towers with rotating beacons at 100 mi intervals between big cities (almost all are gone but every once in a while you spot one out in the countryside). In other words, with the entire sky to fly in airliners are following the equivalent of railroads in the sky.

As you can imagine, this introduces some inefficiencies in routing! The airlines would desperately like to go to "Free Flight", which would allow them to route airplanes as more or less as desired (this is a vast simplification for you aero-nauts out there, and leaves out the problem of hubs entirely).

But Free Flight depends not only on GPS, but the advanced location services that the FAA and other GPS consumers would like to roll out over the next ten years. Those services will require absolutely pure signals on the existing allocated freqs, and possibly more freqs as well.

So they don't want anything messing with the GPS signal.

sPh

Re:SCSI naming

[immanis]

This would make it easy to market to Trailer Parks.

"New, DoubleWide Broadband"

Astronomers get the shaft again

[xX_sticky_Xx]

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.

Re:Astronomers get the shaft again

[kindbud]

Calm down. This technology is much more efficient than conventional broadcast technology. Far less energy is needed to transmit a signal, which is why it can coexist with existing radio infrastructure yet cause no interference. The signal is just too weak, and there is no carrier wave at all. It presents no significant threat to radio astronomy.

It does however, present a threat to users of licensed radio bandwidth, because it eliminates the need to assign freqencies for specific uses. It can coexist with existing radio applications. The potential for competition with traditional broadcasters and spectrum users is what has Sprint, et. al. worried.

It is as if someone figured out how to piggyback signals on the PSTN without needing the cooperation of the Bells, and without any impact on existing applications of the cable plant. Only Sprint does not own the air, like the Bells own the wires.

I guess now we get to see who owns the FCC. This has been a long time coming. I first read about nano-pulse radio almost 10 years ago, when TimeDomain first began petitioning the FCC for permission to conduct tests.

What the hell is the FCC Thinking?

[bourne]

"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?

Re:What the hell is the FCC Thinking?

[MadAhab]

No kidding. It's like watching someone get kneecapped by gangsters and concluding that the local economy must have lots of healthy competition. The reality, of course, is that having bent the rules to within an inch of their lives in order to better kneecap the competition, the bells have basically been told they can use a gun instead.

I can't believe that Powell knows ANYTHING about the state of broadband in the US; this basically grants the commercial monopoly to the Bells, and the residential monopoly to the cable co's. This will make broadband more expensive and slow its expansion into new areas. He better be following this up with something else (like feds mandating coverage areas) or this is a prescription for failure.

Re:What the hell is the FCC Thinking?

[Wesley Felter]

Those wires were put in the ground by RBOCs who had government-granted monpolies. The RBOCs can't get a monopoly and escape regulation at the same time.

RFI

[Detritus]

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.

NPR

[hether]

had a story about this on Morning Edition this morning.

Here's the audio file of the segment:
http://www.npr.org/ramfiles/me/20020214.me.07.ra m

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.

Cringely's UWB article is somewhat misinformed

[Anonymous Coward]

A bit of context is in order regarding the potential conflicts between UWB and the Global Positioning System (GPS). Robert Cringely's article, referenced in the parent post, is a good example of someone who doesn't fully understand the technology in question making assertions that are substantially incorrect.

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

It's from radio terminology of generations ago

[Ungrounded Lightning]

Since when did SCSI terms because the naming noveau trend? UltraWide.

It's from radio terminology from (human) generations ago.

ELF (extremely low frequency)

VLF (very low frequency)

LF (low frequency)

HF (high frequency)

VHF (very high frequency)

UHF (ultra high frequency)

microwave (microwave - subdivided in to bands designated by one or two letters which HAVE changed)

IR (infrared)

X-ray (x-ray)

Gamma ray (gamma ray)

I think there may have been a medium frequency but I'm not sure. There's also:

IF (intermediate frequency) which is unrelated, referring to an internal signal in a superheterodyne receiver.

RF (radio frequency) which is more generic, covering everything from ELF to UHF or perhaps microwave, although its use tends to drop off outside the range between LF and HF.

Similarly there was narrow band and wide/broad band (referring to signal bandwidth significantly less than, or more than, that of AM or early-version FM signals modulated by telephone-quality voice). It's logical for radio engineers to apply the same set of modifiers when they start working with more extreme schemes and have to differentiate them from previous technology.

Re:Side issue: Don't use cell phones in planes...

[Detritus]

NASA's Aviation Safety Reporting System (ASRS) database has a large number of reported incidents where cellular telephones, and other electronic devices, have caused interference with aircraft communications and navigation equipment.

Good intro about UWB "Fact and Fictions"

[SysKoll]

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:

• Ultrawideband facts and fictions, a great intro to UWB principles
• Ultrawideband companies gear up for FCC ruling, mostly about FCC politics
• UWB MACs: build or borrow?, mostly about UWB network card engineering

-- SysKoll

Re:Higher freq==More bandwidth.

[Graymalkin]

You'd be limited with UWB in "bandwidth" which should read transmission capacity only by the speed with which you couple pulse a radio signal. If I can get 100 pulses of a 30m signal that is a hundred bits per second I can send you. The more pulses I can transmit the more data I can transmit. At least this is the best understanding of UWB I have. Old habits die hard for a lot of people. Here is a good EE Times story about UWB.

legitimate concerns

[markj02]

Concerns about UWB interference are legitimate. Sprint is not alone in them. Amateur radio operators and many others are also concerned about interference from UWB.

In fact, there is no question that UWB interference occurs. The question is whether one can allow UWB to be used at any power level without seriously disrupting normal radio traffic when it becomes widely adopted.

Of course, UWB is no threat to other UWB systems. Therefore, UWB licensees would not be opposed to it. In fact, one might well interpret UWB to be an attempt at doing an end-run around current channel allocations, and, ultimately, an attempt at forcing anybody who wants to have some sort of reliable radio communications to buy proprietary UWB technology. Whether it actually is or not depends on the level of interference it causes when deployed widely, and that is still an open question.

In other words, there is no reason to rush UWB to market--we can take our time testing the technology. In fact, there is no real reason for the FCC to approve UWB before the patents run out--why should we increase the noise floor of all our channels for the benefit of a single patent holder? If UWB is still interesting after the patents run out, great.