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-   -   Simple sinusoidal wave can't convey information? (http://www.physicsforums.com/showthread.php?t=655924)

 Mesmerized Nov30-12 02:11 PM

Simple sinusoidal wave can't convey information?

Hello,

Here http://www.mathpages.com/home/kmath210/kmath210.htm it is written that "...in order to actually convey information, a signal cannot be a simple periodic wave...". I've met this statement in several other places too, this one is just for reference.

What does that mean that a simple sinusoidal periodic wave can't convey information?

 jtbell Nov30-12 02:22 PM

Re: Simple sinusoidal wave can't convey information?

How would you convey information with such a wave?

 AlephZero Nov30-12 02:59 PM

Re: Simple sinusoidal wave can't convey information?

A "simple sinusoidal periodic wave" in this sense continues for all time (both in the past and in the future) with the same amplitude and frequency.

That might be different from a "common sense" idea of what the word "simple" means.

 Rap Nov30-12 07:27 PM

Re: Simple sinusoidal wave can't convey information?

To convey information, you need at least two "words". One word gives no information - If your answer to every question was "yes", your answers would have no value at all, they would carry no information. A simple sine wave is like one word, it carries no information. If you had two possibilites, a sine wave or no sine wave, then you could transmit information, like "yes" or "no".

 Mesmerized Dec1-12 01:47 AM

Re: Simple sinusoidal wave can't convey information?