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Comments from Frankston, Reed, and Friends

Thursday, January 27, 2005

BobF at 8:09 PM [url]:

Single Frequency Signaling and Single Hop Signaling

It�s hard to argue against what seems natural. After all, today�s wireless communications industries and policies seem to work very well. The established technologies are not at all natural � they are choices borne of century old ideas that are long due for reexamination.

To level the playing field we need to give the old technologies neutral names.

SFS � Single Frequency Signaling. A 19th century concept modeled on the tuning fork. Each tuning fork oscillates at a single frequency. A tuning fork that vibrates 278.4375 times per second sounds like and is the note middle C. If you have two tuning forks with the same frequency, vibrating one will cause the other to start vibrating. Thus you can tune into a given frequency if you have the right tuning fork.

The idea was supposed to be used for the harmonic telegraph but it wasn�t until the invention of the vacuum tube and wireless communications in the early 1900�s that it became feasible. The need to share a common wireless space required a way to sort out the various signals make it necessary to find some solution.

The problem with SFS is that you have to make sure that only one transmitter uses the given frequency. Otherwise you couldn�t sort out the signals � we call it interference. Inteference is a consequence of SFS and not fundamental.

The solution was to create a dead zone in which no other transmitters were allowed to use a given frequency. Since there were only a few transmitters in those days � it was a new technology � it seemed feasible to police them. Today we have billions of transmitters yet have internalized the requirements of SFS to the point that we accept not only regulation of the transmitters but regulation of speech.

FSC � The Federal Speech Commission. When �wireless� was new it didn�t seem necessary to distinguish between the word �communications� as a term for the meaning being communicated and the technology used to transport speech itself. We live with the legacy of that sloppiness. We need to be careful to distinguish the transport (tele) from the meaning (communications). We can write this as tele/communications and avoid treating them a single concept and thus justifying giving transport providers control over what we can say and to whom.

One consequence of this confusion is that the agency which regulates radio is the Federal Communications Commission. It doesn�t just regulate technology, it acts as a Federal Speech Commission.

SHS � Single Hop Signaling. AKA Shouting. If you want to talk to a friend far away you just pick up the phone and call. In today�s technology that can be implemented by converting speech to packets and sending it over a network.

In the world of �wireless� we have transmit with enough power (i.e. shout) to reach the receiver directly. There isn�t even the concept of packet routing! You either have a direct connection or no connection at all!

This is rude and crude. Since SHS is often used for SFS we have to create a large dead zone that covers the possible shouting distance. No other transmitter can use the same SFS frequency within the zone lest it cause interference. It�s a crude system � if you are beyond shouting distance you can�t get the signal.

Using audio over the Internet is far simpler, creates no dead zone and has no limit on distance! Why would anyone accept the restrictions of SHS?

SFS and SHS seemed wonderful in their time just as leeches seemed essential to 18th century medicine. We pay a high price for SFS and SHS in a technical policy that protects them from newer technologies that can do far better. They aren�t just inefficient but toxic � we have to create a dead zone around SFS/SHS to avoid �interference�. The bureaucracy created to police the ownership of radios goes further and regulates speech, not just technology.

In the United States we require extraordinary justification for restrictions on speech. Coddling obsolescent technology doesn�t meet this test. Ignorance of the laws of physics is hardly a justification for such blatant disregard for the Constitution.

The restrictions on innovation required to protect SFS and SHS come at a great price both in restrictions on speech and prohibitions on innovations that drive the economy of the US and the world.

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