3 ms·

> would open more unlicensed space, on more useful frequencies Which spectrum do you think should be reallocated to mobile use? > This "natural scarcity" is a

> would open more unlicensed space, on more useful frequencies Which spectrum do you think should be reallocated to mobile use? > This "natural scarcity" is a property of the deployed technology, not of the universe. What frequencies do you think should be used for mobile voice and data that are not already?

wahern 9y ago
Required reading: https://spectrum.ieee.org/telecom/wireless/the-end-of-spectrum-scarcity https://www.salon.com/2003/03/12/spectrum/ Basically, the argument is that interference (as understood in spectrum policy) is a myth. The channel capacity of a frequency band is a limit between two distinct physical points--it's not some global (or even local) limit. If you put two pairs of broadcasters and receivers in the same room using the same band, the laws of nature don't require that the available capacity to each pair be cut in half. It's the same as it was before for each pair; any reduction in throughput is merely a limitation of their particular technology. As sensitivity improves; as algorithms improve; as processing power increases; you can asymptotically approach your original (uncontended) throughput even as more transmitters join the fray. The above articles are fairly old, but their arguments have born out, and the fundamental science isn't contested. MIMO, beamforming, software defined radio, and other approaches are now widespread and have permitted orders of magnitude more _aggregate_ throughput for the same geographical area, even as the number of transmitters has dramatically increased. And things will only continue to improve for the foreseeable future. It's not literally true that interference is a myth. And there are fundamental physical limitations that we'll eventually bump up against. But those fundamental limits are beyond the horizon. In the context of historic and contemporary spectrum policy, interference is indeed a myth. The above technologies have come to fruition slower than free spectrum proponents argued. But their argument has always been that as long as government treats spectrum as scarce and grants legally protected monopoly rights, there's less market incentive to develop those technologies. The fundamental argument isn't that we need to add more bands to mobile, but that we need to remove (or at least loosen) the regulations which artificially constrain contention. If market participants had to deal with more band contention, there'd be more incentive to improve their technology to restore the service quality. As long as you don't have malicious people intentionally trying to disrupt the system, the argument is that market incentives alone would spur technological improvements at least as fast as contended usage grew. Of course, for the deployed technology at any particular point in time, more spectrum is better. But the argument here is about optimal long-term policy, not about the best way to ensure first responders can communicate 6 months from now.
- Aloha 9y ago
  There is a rational talking point relating to a higher noise floors causing smaller range and higher bit error rates. For CDMA network P/N solution is a real thing.
- grandalf 9y ago
  This is an interesting argument. I'm aware of it but wasn't aware that the other person was referring to it in his post. I certainly think it would be interesting to have the FCC allocate a band that could be used in a less regulated way such as you describe. It's a very interesting area of SDR and game theory and I've actually put a bit of thought into how such an ecosystem might work after hearing a talk about the DARPA Spectrum Challenge. So I don't disagree with your point at all, and think that the FCC should allocate some spectrum to this sort of deregulated scenario. Perhaps if it also required that all protocol and modulation approaches be open sourced that would help participants to coordinate usefully. I think that we are far from the limits of physics across most of the network, but there are likely some congestion patterns in dense areas that create complex intermod scenarios that would make a system like this somewhat brittle until the ecosystem evolved to find a cooperative equilibrium of some sort. In addition to MIMO, I'm interested in things like using TDM and awareness of harmonic and intermod characteristics to create various emergent latency "contracts" that correlated with different frequency ranges and time slices, so that participants that did not need low latency could create significantly less interference than they otherwise would, and participants could cooperate based on the data rate and latency requirements of other nearby nodes.
  - NotSammyHagar 9y ago
    why would it be different than wifi's 2.4 and 5 ghz bands? those are open, but don't penetrate far because they are high freq. it works but there's tons of things making it unreliable.
    - rayiner 9y ago
      WiFi works in part because it doesn’t carry very far. The unclicensed band strictly limits output power, which limits range which limits the potential for interference.

wahern 9y ago

Required reading: https://spectrum.ieee.org/telecom/wireless/the-end-of-spectrum-scarcity https://www.salon.com/2003/03/12/spectrum/ Basically, the argument is that interference (as understood in spectrum policy) is a myth. The channel capacity of a frequency band is a limit between two distinct physical points--it's not some global (or even local) limit. If you put two pairs of broadcasters and receivers in the same room using the same band, the laws of nature don't require that the available capacity to each pair be cut in half. It's the same as it was before for each pair; any reduction in throughput is merely a limitation of their particular technology. As sensitivity improves; as algorithms improve; as processing power increases; you can asymptotically approach your original (uncontended) throughput even as more transmitters join the fray. The above articles are fairly old, but their arguments have born out, and the fundamental science isn't contested. MIMO, beamforming, software defined radio, and other approaches are now widespread and have permitted orders of magnitude more _aggregate_ throughput for the same geographical area, even as the number of transmitters has dramatically increased. And things will only continue to improve for the foreseeable future. It's not literally true that interference is a myth. And there are fundamental physical limitations that we'll eventually bump up against. But those fundamental limits are beyond the horizon. In the context of historic and contemporary spectrum policy, interference is indeed a myth. The above technologies have come to fruition slower than free spectrum proponents argued. But their argument has always been that as long as government treats spectrum as scarce and grants legally protected monopoly rights, there's less market incentive to develop those technologies. The fundamental argument isn't that we need to add more bands to mobile, but that we need to remove (or at least loosen) the regulations which artificially constrain contention. If market participants had to deal with more band contention, there'd be more incentive to improve their technology to restore the service quality. As long as you don't have malicious people intentionally trying to disrupt the system, the argument is that market incentives alone would spur technological improvements at least as fast as contended usage grew. Of course, for the deployed technology at any particular point in time, more spectrum is better. But the argument here is about optimal long-term policy, not about the best way to ensure first responders can communicate 6 months from now.

Aloha 9y ago
There is a rational talking point relating to a higher noise floors causing smaller range and higher bit error rates. For CDMA network P/N solution is a real thing.
grandalf 9y ago
This is an interesting argument. I'm aware of it but wasn't aware that the other person was referring to it in his post. I certainly think it would be interesting to have the FCC allocate a band that could be used in a less regulated way such as you describe. It's a very interesting area of SDR and game theory and I've actually put a bit of thought into how such an ecosystem might work after hearing a talk about the DARPA Spectrum Challenge. So I don't disagree with your point at all, and think that the FCC should allocate some spectrum to this sort of deregulated scenario. Perhaps if it also required that all protocol and modulation approaches be open sourced that would help participants to coordinate usefully. I think that we are far from the limits of physics across most of the network, but there are likely some congestion patterns in dense areas that create complex intermod scenarios that would make a system like this somewhat brittle until the ecosystem evolved to find a cooperative equilibrium of some sort. In addition to MIMO, I'm interested in things like using TDM and awareness of harmonic and intermod characteristics to create various emergent latency "contracts" that correlated with different frequency ranges and time slices, so that participants that did not need low latency could create significantly less interference than they otherwise would, and participants could cooperate based on the data rate and latency requirements of other nearby nodes.
- NotSammyHagar 9y ago
  why would it be different than wifi's 2.4 and 5 ghz bands? those are open, but don't penetrate far because they are high freq. it works but there's tons of things making it unreliable.
  - rayiner 9y ago
    WiFi works in part because it doesn’t carry very far. The unclicensed band strictly limits output power, which limits range which limits the potential for interference.