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The Illusion of Spectrum Scarcity
Codeine writes "Presentations
to the Technical Advisory Council (TAC) of the FCC by Vanu Bose "Software
Radio: Enabling Dynamic Spectrum Management" and by David
Reed "How
wireless networks scale: the illusion of spectrum
scarcity." Counterintuitive results from multiuser information theory,
network architectures, and physics: Multipath increases capacity, Repeating increases capacity, Motion increases capacity, Repeating reduces energy (safety), Distributed computation increases battery life, Channel sharing decreases latency and jitter. Highly recommended presentation suggesting that the cost of spectrum management by "exclusive property rights" mandated by the State outweighs the advantages we could obtain
from a new model that acknowledges physics and the 70 years of receiver development since the regulatory model was adopted at the time of the sinking of the Titanic."
I want technologies that can let my 802.11b network at home work without interfearing with my cordless phone and 2.4gig audio/video transitter and reciever.
Strangely enough, these are all on unlicenced bands. Sounds like we still need the regulatory bodies to keep the spectrum in some semblance of order.
This is not to say that we shouldn't look into the technologies (quite the opposite). We're just simply not there yet. It would be good to set aside some spectrum for this, though, as a playground for developing new transmission techniques and receiver designs.
"I have opinions of my own, strong opinions, but I don't always agree with them." -- George H. W. Bush
This is a philosophical discussion, but let's also look at the technology.
There are reasons to control. As a licensed radio ham (VA3MVW) I can assure you that if everyone were allowed to broadcast on shortwave ( 30 MHz) we'd have chaos. A kid in Brazil who uses $15 in parts to create a 10W shortwave transmitter can make an entire band unusable in all of Europe. Shortwave covers the world and there is very little bandwith - all of shortwave is only 30 MHz.
The reason things are getting easier now is twofild: technology and physics. Technology, because we can now transmit on GHz frequencies - unheard of just a few years ago. And physics: if you go up in frequency, bandwidth becomes almost infinitely available, antennas become shorter, and range becomes shorter (so less interference).
In other words, good reasons to control low frequencies and good reasons to allow much on wide bands of high frequencies. Which it seems to me is exactly the way it is happening.
Michael
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BDOS ERR ON A:>
then it relays signals a short range to its neighbors...and doesn't broadcast all over the world. Spectrum at HF _is_ a scare resource because it bounces all over. But at line of sight frequencies, if radios have relaying and forwarding capability, then the total capacity grows with the density of radios.
Imagine every cellphone as repeater and network router able to forward several connections and software able to manage such a dynamic network. Then each connection only has RF signals that spread out around the path between all the routers. This means less radio signals falling on places that don't want to receive the signal.
Well, first of all, the market would definitely help out in this fashion -- if someone is hijacking your TV show that you're watching, notably, an advertiser, would you go out and purchase that Whopper or that Nissan or those Nikes, knowing full well they are paying for some spammer to overrun the show you're watching? I think not.
Without SOMEONE paying for the transmission costs, the blurbs won't last. And whoever pays for them will definitely see a huge backlash, even if just a few percentage of the viewers object to the frequent interruptions.
As a libertarian, I have fought for many years to try to convince people that if the airwaves are indeed public, and I believe all communications is speech (including computer code), Congress shall pass no law infringing on my right to speak.
If I am in a room with 10 morons spewing corporate advertisements out of their boomboxes, and I want to blast my boombox 3 times louder, none of us will get anything accomplished -- the same is true of the airwaves. Why doesn't the FCC control the vocal frequency band of transmission, it is no different than someone broadcasting a low-powered radio transmission, and it is done over airwaves.
Finally, after years of screaming that we have too much bandwidth, and people telling me I'm nuts, scientists who aren't bribed by the broadcast industry are coming out and showing that I've been right all along.
Now if only real scientists would start coming out and blasting the socialist fraud we call the "decaying environment." Oh, they already have. They're called the founders of Greenpeace, and they know the truth about the current socialists running that organization.
Freedom = Responsibility.
Government = Corporate Abuse
I think that bandwidth could be used a lot more efficently. Right now we are treating the spectrum like the analog medium it is. But a digital treatment is more justified. If we were to break everything up into packets, use reapeaters what not, we could achieve a far more efficent utilization of the airwaves. Nearly all bandwidth is allocated to something. But at the same time, most of it is unused at one instant. Using packets like the internet does could do a far better better job of utilization.
HOWEVER, it would require more control, not less. The government would need to mandate all radio equipment manufactors meet new standards (much more rigorous than they do now). All legacy equipment would need to be replaced. New laws would need to be drafted to regulate the medium better.
But so much more is possible. We're using an abundant natural resource like cavemen, and we could do better.
If I set up a 138db WW II vintage air raid siren in my back yard for fun and start testing it out -- in all likelihood I'll be dealt with by the local authorities who will be called in by just about everyone in a 1km radius.
On the other hand, if I'm talking to my neighbor over the back fence and some Feds showed up to stop our "noise" the local authorities (presuming this is a jurisdiction that doesn't receive a lot of Federal subsidies) would likely arrest them.
Seastead this.
Even without increased capacity, there are ways to share the airwaves without having anyone own them.
Sorry, but the idea of the government -- or a company -- controlling or having the rights to a certain frequency is about as obnoxious as the government saying they own all the air in the US.
The very same technology that regulates printing in LAN's at universities can regulate the airwaves. Two people send a request to a printer to print a document at the same time; the printer doesn't know which to process first, so it waits a random number of milliseconds (different # for each terminal) and then sends a repeat request; whichever one gets back first is printed first. Another way to do it would be to have the printer just randomly pick one. An alternate, and superior way, would be for the printer to print the shorter document first.
Similar algorithms could govern who is using any particular frequency at any particular time.
Furthermore, let us not forget that we don't have to deregulate the entire spectrum in one swoop. We could deregulate half of it first and let the technologies for controlling access to that half perfect.
The point is, everyone should have access to the airwaves. It should not be based on how much money you have. No one has any right to claim they own the air or the airwaves, just as no one has the right to claim they own their air: that's bullshit.
social sciences can never use experience to verify their statemen
Similarly you talk about fighting a fire with nothing more than a fire extinguisher - why the hell wouldn't a commercial service exist like with everything else you need? Fire protection would become a branch of the insurance industry like it was in the past.
Your argument is inconsistant.
Okay, an analogy. You're at a cocktail party where there are a few hundred people in the room. For some reason, everyone's feet have been glued to the floor. Instead of panicking, they try and continue their conversations.
As in every cocktail party, people soon get bored with the people next to them. They can't go visit someone else, because of the whole "feet stuck to the floor" thing.
At this point, the participants have two choices: They can either shout across the room or relay messages through third parties. If they take the shouting root, the effective bandwidth of the room drops to the point where only one or two conversations can be held at the same time. By relaying the messages through the people next to them, they can have dozens of conversations going on at the same time. Hence, a higher effective bandwidth.
So, instead of visualizing the repeaters as increasing the range, imagine them lowering the strength of the signal needed to take the message across the same range. Thus, you have a higher effective bandwidth.
If this analogy is either incorrect or just stupid, feel free to mod it into oblivion.
You want the truthiness? You can't handle the truthiness!
The trouble is is that you are talking about the technology of 60 to 70 years ago. The point the article makes is that in the modern world it is just an anachronism, rather like a lot of what the government does. Technology has moved on and there isn't a call for the solutions of 70 years ago - solution that in all fairness were enforced by governments ultimately grabbing hold of the medium for propaganda in the run up to WWII. Merely because ham radio was ruined by "the tradgerdy of the commons" doesn't mean that all non-government wavebands have to be commons. In fact, can you think of a single common not held there by a government agaency anyway? Freeing the spectum from the FCC would not necessarliy give way to a commons, any more than property would revert to commons without the IRS. In fact life would be a lot easier.
"Multipath increases capacity, Repeating increases capacity, Motion increases capacity, Repeating reduces energy (safety), Distributed computation increases battery life, Channel sharing decreases latency and jitter."
People seem to forget technology is the great equalizer when it comes to limited resources. It's why we won't run out of oil in 2010 and why crowding won't remain a problem. It's using what you have more effciently, not basing your results on a static idiology when the world you live is in a dynamic progression.
You need a FREE iPod Nano
Acutally, the article refers to ways in which networks of devices that not only communicate with a base station (i.e. traditional cell phone) but with each other, even repeating traffic for each other (i.e. a mobile version of the internet!) could increase total capacity while lowering power output.
Better routing (rather, using routing at all) will make all the difference.