One of the few written at a public level that is accurate - there is nothing in physics that suggests there should be a spectrum shortage. All of that is an artifact of policy - policy that was set forth in the 1920s and had to deal with the antiquated receiver technology of the time.
the key point (caveat - David is a friend)
Because spectrum is seen as a finite resource, with allocation a zero-sum game, the rule has been grab it while you can. The more one carrier can amass for its exclusive use, the less there is for the others—who are then at a competitive disadvantage. In essence, then, the scarcity of wireless spectrum is an artificial one, exacerbated by the way it is allocated.
As explained by David Reed, one of the architects of the internet and a former professor of computer science at the Massachusetts Institute of Technology, photons—whether they are in the visible, radio or gamma-ray part of the electromagnetic spectrum—simply pass through one another when they cross paths. As they do not occupy the same space, they cannot cause interference.
The only thing that distinguishes one type of photon from another is its frequency—ie, its energy level. Thus, to all intents and purposes, radio and light are the same thing and follow the same laws of physics. Therefore, in licensing frequencies to broadcasters, the FCC is essentially trying to regulate colour, jokes Dr Reed. His point, though, is that there is no more scarcity of wireless spectrum than there is a shortage of, say, the colour purple.
On a more serious note, Dr Reed believes the hoary metaphor of spectrum as real estate that needs to be subdivided to avoid interference is misleading. The rise of “co-operative” wireless networks—where the network architecture organises users in a way that allows them to help one another transmit and receive messages—makes a mockery of ideas about spectrum being as finite as land. Experiments show that as the number of users in a co-operative network increases, its capacity actually rises. So much for a precious and diminishing commodity.
All this has been known for a decade or more. Yet spectrum continues to be allocated as if it were a finite resource which, like common land, needs to be carefully managed so as to avoid some “tragedy of the commons” caused by over-exploitation and interference. “When the capacity of the commons can increase with the number of users,” notes Dr Reed, “we clearly need a different regime to allocate capacity among users.”
A couple of nits with the article - the "better" propogation of signals at 700 MHz and WiFi being "unlicensed" (it is "licensed by rule" and shared with other services. It allows unlicensed operation - a big difference!).
Unfortunately it will be quite awhile before we get modern radios.