I’d like to see how to design a system of that allows an infinite number of transmitters to communicate with an infinite number of receivers on a particular radio frequency in a given location without interference (the impaired ability of receivers to extract bits from a radio signal,) or simply a large number of transmitter/receiver pairs. In particular, I’m looking for a coding system that suspends Shannon’s Law.

I’d also like to see information about the credentials of the so-called experts on spectrum cited by this article, as I’m not aware of any academic papers, patent filings, or products that exploit the infinite spectrum concept that can be attributed to the three experts (or to anyone else.)

We know that Cooper was one of the eight inventors listed on Motorola’s cellular patents in 1975, and also that Cooper was a co-inventor of ArrayCom’s SDMA patent from the early ’90s, but ArrayCom has not been successful in creating any infinite spectrum systems. SDMA has extensibility limits, as does CDMA. They both achieve simultaneity by subdividing the code space, and this approach does not go to infinity.

As far as I can tell, neither Reed nor Isenberg has worked with actual spectrum systems in either a research or a product development setting, but I’d love to see evidence to the contrary in the nature of academic papers, patents, or products.

Finally, I don’t understand why the claim is made that the carriers invented the spectrum crisis. The National Broadband Plan forecast a spectrum crunch two years ago, and not only was it not a carrier product, Isenberg was a member of the team that produced it.

It seems a bit more prudent to base spectrum policy on science than on the speculation of non-experts writing in the popular press. Call it an elitist bias if you wish, but I think science is worthwhile.

[I'll cross-post this comment to hightechforum.org.]

this was laid bare by Sanford Bernstein analyst Robin Bienenstock last year — excerpting from under “Sad prospects for improvement in US mobile networks”:

… Sanford Bernstein analyst Robin Bienenstock noted that a primary reason why US [cellular/mobile] networks are so pathetic is because the American government doesn’t regulate how carriers build their [cellular/mobile] networks as European nations do, providing the example of rules mandating a minimum number of base stations that, if not achieved, will result in the carriers losing their spectrum allocations.

“Let’s take California and Spain as an example, ” Bienenstock wrote. “Telefonica has some 33,000 base stations in Spain (yes, miserable, economically imploding Spain). Conveniently, California is a similar size, has a similar topography, and has very similar population density. In California, AT&T has just over 6,000 base stations. The spectrum allocation per pop in these two operators (TEF in Spain and AT&T in California) is remarkably similar. A similar analysis looking at New Jersey and Massachusetts vs the Netherlands shows similar results.

“Why are European [cellular/mobile] networks so much denser than American networks? In large part the answer lies (again) in regulation. In Europe, the spectrum auctions of last decade came with ‘use it or lose it clauses’ that obliged operators to build a minimum of base stations or face sanctions from fines to loss of spectrum. The result is clear to any American visiting Europe… and more frustratingly obvious to any European visiting the States.”

http://dslprime.com/a-wireless-cloud/61-w/4466-us-wireless-75-fewer-basestations-than-comparable-europe

this manufactured “Spectrum Crisis” and the bamboozlement/deception/hoodwinking/snookering by the carriers has been going on since “The Red Herring fast one” PAC*TEL pulled off shortly after the original A & B band 20 MHz CMRS allocations were deployed in Los Angeles on the grounds that the coming Olympics to the area was gonna see one big cellular traffic jam of massive proportions…

PAC*TEL successfully faked out the FCC in to giving them an extra 5 MHz of Totally Unnecessary and Undeserved (and free!) CMRS 850 MHz spectrum (instead of just investing in and developing additional sectorized) cell sites… the same lies and deceptions have been “working well”/promulgated/promulgating ever since…

hopefully articles like the NYT, knowledgeable and respected folks like Cooper, Isen and Reed along with blogs like this can finally get The Facts/Truth out to educate/enlighten Our ignorant/naive journalists, FCC decision makes, members of congress and other responsible parties. it’s High Time an end was put to this shameful “Spectrum Crisis” sham…

the base station vendors ought to love you all and this message, what with Europe having around 5.5 times more base stations deployed in similar spectrum, topography and population densities than we “here”…

geoff goodfellow

The Article “Traffic Jam in the Ether” (NYT Wednesday, April 18, 2012) presented balance views (including mine) of the so-called “spectrum crisis” but it may have missed two important points. First, there is agreement among all parties that much more spectrum capacity will be needed in the coming years. Increased Internet traffic will require 20 to 40 times more wireless capacity than exists today. The most optimistic estimates of spectrum available to operators by redistributing spectrum from other services such as the military and television would add only about 20 or 30% of additional spectrum to their existing portfolio. This is insignificant; adoption of existing and new technology is the ONLY solution Secondly, the “traffic jam” is not the only problem; wireless data services are much too costly today. Advance technologies such as smart antennas and dynamic spectrum access will, when adopted, substantially reduce the cost of wireless data.

Rather than trying to reassign inadequate segments of spectrum among licensees, we should be aggressively, in effect, create new spectrum by using the spectrum more efficiently. Technological advances have made spectrum virtually infinite for more than a century and we know enough to be confident that this will continue for at least 50 years.

http://en.wikipedia.org/wiki/Low_frequency

and is used for navigation, submarine communications, timekeeping and experimental / hobbyist “Lowfer” operations:

http://en.wikipedia.org/wiki/LowFER

If there is a stampede of giant telcos who want to bid on LF licenses, I haven’t seen it.

With regard to the spectrum crisis, most spectrum users, whether commercial, nonprofit, governmental or scientific, argue that they suffer from lack of spectrum. The crises are manufactured, perennial and typically intended to deliver more spectrum exclusivity to the complainants.

I think that makes the substance pretty clear.

About “low frequency spectrum” you say “It is not much attenuated by walls, leaves and air the way higher frequency spectrum is.” That’s not true.

With respect to air, the atmosphere is roughly transparent from 30 MHz to 10 GHz; the photons go at the same speed and they are not absorbed. Radio astronomers know this. “Radio engineers’ who believe there is more path loss at higher frequencies don’t understand the receiver assumptions that are built into the Friis equation.

With respect to buildings, both low frequency and high frequencies are substantially attenuated by masonry walls and almost totally attenuated by metal siding. They are also both moderately attenuated by wooden walls and by sheet rock. Most RF enters building via the windows. The difference is higher frequencies are more scattered, especially as the wavelength becomes equal to or smaller than the window dimensions. Scattering is bad for 20th century radio receivers but is good for higher order MIMO systems (4×4 or 8×8) which are just beginning to emerge today.

With respect to leaves, the situation is more complicated and I haven’t found as many useful measurements as are available for the atmosphere or for construction materials. There is certainly rich scattering that increases with frequency (i.e. with shorter wavelengths). I’ve seen one paper that suggests RF absorption in maple trees peaks when a half wavelength approximates the leave size and then decreases at higher frequencies. The problem is most of the modeling of RF through foliage that I have seen (ITU, mobile industry, etc.) assumes 20th century radio receivers. The other area being modeled is foliage as seen by satellites, Neither are useful for understanding what future, higher-order MIMO systems might accomplish. If anyone can point me at useful data on RF through foliage, I’d appreciate it.