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FCC Petitioned to Restrict 2.4GHz Band
Mean_Nishka writes: "Internet News is reporting that satellite radio provider Sirius is petitioning the FCC to regulate and hinder providers of 802.11b based networks. Sirius claims their radios operate at frequencies only 55mhz lower than wifi's range, and fear that Wifi users could interfere (especially mobile and internet service providers). This could effectively kill free networks nationwide..."
And those frequencys are .2 MHz apart!
Besides, I was under the (mistaken?) impression that one of the selling features of this satellite radio crap is that it is all digital.
Thus said, could there ever be enough bleed through to completely wipe out their signal?
OR is Sirius more afraid people will start driving around town listening to Shoutcasted streams on 802.11 networks? Oh yeah, gee, I wonder.
- JoeShmoe
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-- I wonder which will go down in history as the bigger failure: the War on Drugs or the War on Filesharing
1) Which is more important, satillite radio or wireless internet access?
2) Which is the FCC most likely to understand better?
3) Which side has more money?
I think it's obvious which side will win out (if there can be only one, that is).
[PowerPoint] is a tool for capitalist presentation
This isn't that big of a deal.
:: The Critically Acclaimed New Linux Site. Ads Not Included.
"Besides being limited in size by FCC regulations, the 2.4-GHz band in which 802.11b products operate is becoming overcrowded. This is the same band that the long-awaited Bluetooth products, microwave ovens, some wireless speakers, and the latest wireless telephone handsets call home. Today's products already eke out all the performance they can within the band's regulatory structure, leaving very little bandwidth to accommodate next-generation needs such as video broadcasts and voice channels.
The most likely place for wireless expansion is the 5-GHz band. Its comparatively wide- open space could provide increased speed and better control over the quality of transmissions. Plans are afoot on both sides of the Atlantic to devise a suitable protocol for the 5-GHz band. Not surprisingly, the U.S. and Europe are pursuing two different and non-interoperable 5-GHz protocols."
Read the rest here.
m o n o l i n u x
1. I don't know the nature of either signal, but 55MHz is a decent amount of seperation. If there are pieces of 802.11 equipment which are really transmitting 55MHz too high, their manufactures deserve a bitchslapping from the FCC.
2. If satelite radio receivers are having a hard time dealing with a signal 55MHz away, their manufactures need to send the design teams back to school.
3. If someone is running 802.11 equipment at power levels which overwhelm nearby satelite receivers listening 55MHz away, they probably need to re-engineer their setup to use less power and/or use an antenna with a different pattern.
4. If none of the above scenarios are true, this is probably Sirius looking for a little extra elbow room. If granted, their next move (a few years from now) will probably be to pettition the FCC for use of the now underutilized spectrum.
Despite being a govenment agency, the FCC a knowledgeable technical staff to sort this kind of thing out. Occasionally the FCC even listens to them!
Come test your mettle in the world of Alter Aeon!
802.11 interferes w/ the head-tracker we use at our school for 3D stuff. We basically need a TEMPEST-protected room so we can play w/ our 3d toys.
Maybe sirius should use 3D differential phase decoding to "listen" to a frequency at a location. Basically, two or more antennas allow you to discriminate among different sources, just like how your ears and brain work; as a practical example, using three antennas prevent jamming of GPS by enemy noise sources. The GPS antijam method uses constellation position prediction and real-time kinematic (motion) compensation (doppler shift, etc.) upon the sender's signal and receiver's motion, note this is wholy listener-side compensation, no mods to GPS constellation are needed for antijam technology. If sirius is broadcast-only, then they need to mod their receivers to use this type of technology. Why force restrictions on existing equipment for people trying to be fancy w/ their new toys? Screw em if they can't play w/ others already out on the field.
We can get alot more bandwidth if we use this type of technology along with CDMA-type encoding. It might be slightly more expensive and logistically prohibitive, but economical use of bandwidth demands it.
The biggest trick the devil pulled was letting lawyers become politicians so they can write the laws.
This is HUGE. Many wireless ISPs already functioning with the 2.4GHz range. Plust free networks are springing up like www.seattlewireless.org and www.houstonwireless.org, there are tons. And you say its no big deal that they will have to scrap their equipment? All of them??
Protocols will not eliminate interference. 5GHz has different transmission properties than 2.4 GHz. It a different frequency. Many WISPs were already bracing for this and expect to have to move into 5GHz, but 5GHz is handled just the same as 2.4 so far. 802.11a is already out there at 5GHz.
If the FCC wants to do somethign they need to give a unlicensed range for specifically data communications only.
Honestly, who gives a damn about satellite radio. More people are using wireless internet that satellite radio.
Yep, this most certainly would effect data networks. Does Sirius not understand the fact that the 2.4 band has been available for public use for years now? You'd think they would have performed interference tests with their equipment from day one, instead of waiting until the last minute. This is ridiculous...Sirius may have invested $3 billion, but what about the rest of us who have already invested significant amounts of money outfitting out sompanies with WiFi. If money matters in this matter, then my money matters too.
--It's Pimptastic!--
This crap is gonna go down in flames even faster than Iridium did.
Subscription, NON-LOCAL alleged radio, devoid of all of the values that make radio work in the first place? Bleahh!
Ever turn on AM in the am (giggle) looking for something that's NOT ART BELL? Local color?
That's what satradio is gonne be like in no time. Kiss of death. Nobody's gonna pay for the kind of homogenised drivel satradio will become within (mark my words) two years.
Can't wait to see the pretty lights when they deorbit those puppies luminescently.
THAT, I'd pay money for
>8->
Brak: What's THAT?
Thundercleese: A light switch.. of TOTAL DEVASTATION!
That's it. I'm no longer part of Team Sanity.
You've already spent significant amounts of money on WiFi. If your equipment gets outlawed (and that can actually be enforced), They (being whoever Sirius is acting on the behalf of in this lawsuit...either themselves or some big wireless networking company who might benefit) would have an easier time selling a competing standard, since the incumbent technology would be out, and the manufacturers of that equipment would not be ready with replacements.
And Freemasons run the country.
The fact is that 802.11b channels are only 25MHz wide. And 802.11b equipment is quite capable of working with adjoining 'cells' butted right up against each other. Check out this table. The non-overlappig channels are 1,6 and 11. Total center-to-center separation? 50Mhz between channels 1 and 11 with room for a channel in between. If Sirius has a problem with 802.11b I'm going to hazard a guess it's because their receivers are crap. I'll bet that they are receiving part of the legitimate 802.11b signal.
;-)
I've actually run tests to see how well two access points work if you locate them close together (about 4 feet). You can see a writeup of all the tests I did here: Interference Tests. When I tried to run two laptops connected to two access points on channels 1 and 6, I found a little interference. Not much. Maybe a 20% drop in total thruput. Once I went to channels 1 and 7 (30MHz separation) the two access points operated with no detectable interference at all. The aggregate thruput was basically 2x the thruput of a single access point. (Note that the 209% and 212% results are because I was using laptop to ap traffic as the baseline, but the equipment I was using produced higher thruput in the ap to laptop direction)
While the interference at channels 1 and 6 technically shouldn't happen, no body in their right mind puts two access points four feet apart and tries to run them both at full bore. So the radios could be a little better. But even in this worst-case scenario, all interference disappeared at 30MHz separation. And Sirius is complaining about 55MHz separation? Almost twice the distance?
What Sirius is finding out is that the idea of transmitting from a satallite to a non-directional antenna is extremely hard. That's probably why the other sat radio company XM plans to spend ~$250,000,000 dollars building a system of terrestrial repeaters! It's hard to link to, but check out the 10-Q SEC filing on their web site if you don't belive me. I can't find it now, but another SEC filing in there goes into detail about the need for repeaters because they know their signal can't be reliably received inside a major metropolitan area.
If Sirius has burned thru $3 billion and still doesn't have a reliable system, well boo hoo. The only reliable sat-based communications I know of use directional dish antenna's. (Please don't use GPS as a comeback because it doesn't have to work in a lot of places that a car radio has to, and it carries almost no information in the signal.) Irridium tried it and failed. Sirius apparently can't get it to work, and I'm going to guess that they will soon be history. As for XM, well, I think they got it to work, but only by spending a fortune on repeaters so most of their customers probably aren't even using the satellites! I think XM is going to go down the tubes anyway since they probably need to get at least 1,000,000 paying customers this year to keep going.
So I think Sirius and XM are going to follow Irridium down the tubes. And life will go on. As every good capitalist knows, massive failures prove the resiliancy of our system. That's what's know as "The Enron Axiom".
While nobody paid the government for the frequencies that 802.11, there is a huge amount of business going on it 802.11 equipment. The amount of business thriving off the sale of 802.11 equipment dwarfs what little Sirius has manged to do. Ultimately the FCC doesn't care about the money that comes in from a spectrum sale, it's not like they get to keep it. They care about politics, and what will decide this is who can apply the most political pressure. Can Sirius trump Cisco, Lucent, Intel, and all the other electronics companies making a killing in the 802.11 market? Doubtful.
This sig has been temporarily disconnected or is no longer in service
It's got some good info in it. At the very least, you'll find out that it's part of a bigger request for comments by the FCC on "whether it [the FCC] should change its emissions limits for the restricted bands above 38.6 GHz, and whether the Commision should apply its emissions limits to receivers that tune above 960 MHz." It's also got some of Sirius' technical evidence in support of their claims.
And here's a choice quote:
BTW, this is a public document. I'm not sure if it's on fcc.gov yet but it should be someday...if you can wade through their multiple search engines and multiple data formats. You'll be able to track any replies.