“RESOLVED: OVER-THE-AIR BROADCASTING IS A DINOSAUR AND SHOULD BE ABOLISHED IMMEDIATELY” – Part I: A Tale of Two Network Models
The above looks like a question to be put before a college debating club for argument, but it’s really also a topic that is current and highly relevant for us folks out in the real world. And in fact the “debate” is already underway, and not just within the confines of a single debating hall.
The FCC has in mind making “a few minor changes” in the use of the RF spectrum. Nothing really major of course, at least in their highly informed view. The changes are merely just “some tiny first steps” that would eventually lead to the end of over-the-air television broadcasting. And let’s put some strong emphasis on the word “broadcasting;” this is an important concept.
The Commission has it in mind for the owners of current television broadcast (there’s that word again!) licenses to relinquish (for cash payments) their existing rights to use the public’s RF spectrum, and then for the FCC to re-sell the “liberated” spectrum to the wireless carriers. In principle the carriers would use the newly purchased spectrum to expand the “broadband superhighway” in this country. The FCC’s unstated goal surely must be to boost the US from its currently “dominant” 26th place position in the world ranking of the quality of US citizens’ Internet access (a national evaluation based upon both the channel bandwidth available for the end-user and the cost to the consumer for such access), thus perhaps boosting the US ranking all the way up to…… 20th place, worldwide. Whoopee!
Space doesn’t allow our waddling through the current spectrum shenanigans; the machinations are well documented in the industry press.
If matters flow on unchecked, certainly the curtain will ring down on over-the-air broadcast television within most of our lifetimes. The slowly diminishing use of over-the-air television broadcast signals by the general public (caused, in part, by the public’s abject ignorance that such access exists as a free service) has already somewhat damaged the economic value of a broadcasting license. Thus current broadcasters have less incentive, even in the absence of the FCC’s proposals, to maintain and to develop their RF spectrum holdings. The future is not bright for broadcast television.
Neither is it bright for radio. Technological obsolescence and rapidly increasing metropolitan RF noise levels have hugely hurt AM radio. FM radio, which is not troubled by these technological and noise problems, is in a little better economic shape but it faces a different long-term problem. The public is no longer strongly dependent upon FM radio for delivery of its “songs.” (Perish if the public should ever focus on music more extensively-structured than just “songs,” such as entire Broadway musicals, jazz sets, and even……. (oooooooh) …….symphonies and concerti!) Other media now do the public’s song-fetching chores, especially for our youth. Some of the population already has little, if any, need for or use of “radio.”
The Once and Future Story of Broadcasting
But before we blithely toss over-the-air broadcasting away, let’s step back for a moment and see what we have, before it disappears.
Over-the-air broadcasting was originally developed and then flourished to meet a single need. That purpose was, first in the case of radio, to bring audio-based information in real time to a mass audience. In the later case of television, it was both audio and visual information. Prior to the establishment of these two modes, there was no mass audience, real-time information delivery system in the country. None!
At the junction of the nineteenth and twentieth centuries the telephone and the telegraph could bring real-time information to individuals, while newspapers and magazines could bring delayed information to the masses. But no medium could do both. Broadcast AM radio, when it emerged in the 1920s, began to knit together a dispersed, largely rural country with real-time, mass audience information delivery.
The inventors of over-the-air broadcasting had stumbled onto a technological gem, although they might not have realized it in their zeal to expand the new medium. But the system that they invented was not modeled at all on the only telecommunications “networks” then known, the telephone and the telegraph. Instead the first broadcasters departed on a different route.
As every telecommunications engineer instinctively recognizes, originally the telephone and to a lesser extent the telegraph networks used “point-to-point” network models in concept and operation. By way of explanation, in using this kind of network the calling individual (with the aid of the wire carrier’s employees) established a “circuit” through the network from himself to the receiving party. This dedicated circuit was used only by the two parties that it connected, and other subscribers wishing to use the network had to establish their own separate and individual circuits along it. (That requirement, of course, is no longer strictly true in modern telephone networks.)
“Broadcasting” (a term of agricultural origins, here meaning “to cast [information] broadly”) from its very beginning was a complete break with the telephone network concept. Broadcasting was established on “point-to-multipoint” network model, meaning that one transmitting party could be received by an uncountable number of receiving parties. That is the brilliance of the concept. Allow one high power AM broadcaster to use 10 kHz of the RF spectrum, and perhaps three million listeners to that 10 kHz band of signals will individually and simultaneously receive the information.
That point-to-multipoint model is highly efficient in its use of spectrum. Instead of three million RF-based channels in a wireless point-to-point program distribution system, there is only one. Switch the same network over to point-to-point, and those three million listeners, each with his own private “channel,” would need a total of 30 MHz of radio spectrum. Within the radius of its surface wave coverage, one AM station would use the entire available local spectrum, with no room for any other wireless Service.
Enter, Wireless Broadband and the “Demand Pit”
If point-to-point seems resource-wasteful for a mass, real time information distribution network, it’s only because it is actually wasteful. But that is just what the FCC is proposing to do: tear down the point-to-multipoint broadcasting model and devote the “reclaimed” spectrum to what is essentially a point-to-point wireless Internet service.
That proposed reallocation would feed a bottomless “demand pit.” There will never be enough RF spectrum to house the exponentially-increasing Internet demand! Rational engineers would never endorse the notion of creating point-to-point mass distribution networks on the RF spectrum. The FCC, however, apparently thinks the idea is “the greatest thing since sliced Coors in cans!”
Naturally, a greater number of individual point-to-point channels to serve an increasing number of end-user terminals require more operating bandwidth. If the increasing bandwidth requirements can be satisfied through the establishment of terrestrial copper- or glass-based distribution networks, the demand can (theoretically) be satisfied. More “wire” can be pulled in to supply the additional capacity. If instead the increasing demand is pushed onto the RF spectrum……..well, the supply of usable spectrum obviously is tightly constrained.
This is the rationale for the contention that the FCC’s “notion” of pushing the expansion of the national “broadband highway” onto the RF spectrum is an exceptionally bad one: it cannot permanently satisfy the ever-increasing bandwidth demand, while simultaneously it begins to squeeze out existing information delivery systems that are vastly more spectrum-efficient and -conservative (i.e., broadcasting) as well as other spectrum-requiring telecommunications applications, such as Public Safety.
Is There Hope for Broadcasting – Where Now?
With this brief foray into “message delivery network models” we have hopefully developed a little appreciation for the need to retain over-the-air “broadcasting” as a central part of the nation’s mass audience message delivery infrastructure. In the next several parts we’ll look just a bit at the current “bandwidth” supply conundrum that is causing the squeeze on wireless broadcast spectrum, and then turn to suggestions for the revitalization of broadcasting to bring it back into its central (historical) position in the information-delivery systems pantheon.
What do you think?
“Let’s save the universe for RF!”
The old RF Curmudgeon