Comment by ohazi | Hacker News Reader

Comment by ohazi | Hacker News Reader

Parent Full thread

> incentivize not only more efficient usage through price signaling, but you incentivize research & development into more efficient technologies.

As with software patents, I think there's an argument to be made that this is no longer true. Digital modulation schemes are leagues more efficient than older analog techniques, both in terms of power and bandwidth. Spread spectrum schemes in particular are even reasonably resistant to being plopped on top of each other.

The spectrum ownership scheme allows established players to sit around on their asses using loud, inefficient modulation schemes with huge dead zones in between channels because they don't need to do any better than that.

I think radio technology would be better across the board if spectrum were open, and if people had to compete by using better, more efficient, more interference-immune modulation schemes, or risk getting stepped on by someone else. If we had a system like this, the noise floor would just slowly increase in heavily used parts of the spectrum, rather than what we have now, which is a whole bunch of legally mandated quiet zones punctuated by huge narrow carrier spikes.

The technology to do this exists... you can go buy a broadband SDR and put together a system like this in GNU radio fairly quickly for experimental purposes, but it's not really legal to actually use this anywhere.

The thing is, that the QoS and power efficiency of e.g. LTE isn't attainable if you have uncontrolled interference. It's a general issue with far-side crosstalk.

Interference is largely a property of the specific scheme. 5G schemes are better than LTE when comparing apples-to-apples (e.g. aggregate bandwidth on the same bands in the same geographic area), whatever comes after 5G will continue moving the ball forward, and the theoretical limitations on how much further we can keep kicking the ball are still out of sight.

Thus the question isn't what regulatory regime is best for squeezing the most out of LTE, but rather what's the optimal pace of radio communications evolution and how to achieve it. That's a drastically different type of question that almost certainly has a drastically different answer, or at least a much more complex answer.

Then make it so that frequencies don't get blocked for this long. Make it so that a company has to re-bid every once in a while for spectrum.

Instead of just giving it away or making it all free-reign.

The ideal spectrum allocation scheme would be a by-the-minute rental.

Whenever anyone wants to use spectrum, their device automatically bids and gets allocated whatever size slice of spectrum and transmit power they ask for. Then the device maker or the user pays the bill at the end of the year, perhaps with some minimum free amount each year per person, which could cover all except the biggest spectrum users.

If you didn't like the government allocation scheme, you could rent your own block and do your own sub-allocations, for example some kind of packetized system with microsecond long packets wouldn't want to have to contact a government server for every 1 microsecond allocation.

That gives a strong incentive to use efficient allocation schemes.

An "ideal" scheme is once again derailed by reality, where predictability is valued; where antennas and signal processing equipment are physical objects, that cost money to procure and install, and are subject to engineering limitations which limit their flexibility.

Remember, the free market is only efficient when transaction costs are low.

Could you be more specific? What about this proposed "ideal" scheme is infeasible (specifically the engineering limitations you mentioned)?

As a quick example, I’ve been doing a bit of work with land-mobile radios lately (LMR). We rent a very small slice of spectrum from the government (12.5kHz wide, IIRC), and all of the radios use that frequency. They work anywhere (within the range of our license anyway). They run independent of a repeater or any kind of fixed base station.

If I’m out in the middle of nowhere with my team and we’re using these radios because there’s no cell coverage, a) how would a given radio “bid” on a piece of spectrum, and b) how would the other units in the talk group know to listen to a particular frequency for my message?

That's a neat problem. You may hear N other stations, but they may not hear each other at all. Its very difficult to know whom to tell about coordination information, or even how to calculate it. Solve that, even heuristically, and make a $B

I agree! It’s a very interesting distributed system problem and honestly, I might end up doing some sketching tonight.

Right now it’s easy to know whom to tell about the coordination though: the Canadian government :).

Reply on news.ycombinator.com