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..."

Comments

Three Questions

[Rayonic]

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).

A few thoughts.

[SagSaw]

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!

You dont know what your talking about

[dnoyeb]

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.

Re:Some FCC related facts

[PurpleFloyd]

Blockquoth the poster:

Sirius is a licensed service. 802.11 isn't.

No way. As radio transmitters, 802.11x devices have to be FCC licensed, along with every other piece of equipment in your computer (although radio transmitters like wireless net products have different standards than regular electronics equipment!). The FCC licenses every single wireless networking product, along with all cordless phones, and any other radio transmitter/reciever. As such, the FCC had the opportunity to review each device and determine if it causes out-of-band interference (like the satellite radio people are claiming). My guess is that the FCC will say something along the lines of "tough shit!" because of the fact that Sirius is complaining about interference 55 MHz outside their alloted band. That's ludicrous -- if the tuners are that bad, Sirius should never have released their product. Imagine your new car stereo tuned to 88.1 FM recieving interference from 107.9 FM. You would take the stereo back! Even if you were sitting right next to the 107.9 transmitter, you wouldn't expect much interference - and that's an analog signal. Digital has (or should have) error detection and correction built in. Sirius seems to expect special treatment because of a bad product - I hope to all that is right and holy in this world they don't get it.

Sirius are a bunch of whiners

[BeBoxer]

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". ;-)

Re:Sirius are a bunch of whiners

[revscat]

Wow.

You know, it's guys like you that make me keep coming back to Slashdot. There is that occasional gem shining in the piles of horseshit that makes it all worth it.

Unfortunately, I am frequently the one delivering the horseshit.

- Rev.

802.11 and where the money is...

[sterno]

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.