[OT] Power over radio is it a true thing or just a myth ?

[Michael Vasiliev]

Good, now put back the context you've omitted, take your antenna specs
and prove it with numbers. Solutions that will make the fly-by birds go
poof or yourself arrested and your equipment seized do not count.

Shachar Shemesh wrote:
> Michael Vasiliev wrote:
>> The power of the signal is inversely proportional to the square of
>> distance.
> That is not precisely accurate.
>
> An undirected point source of EM radiation (or any other type of
> energy) transmits energy that expands on a sphere from the point of
> transmittal. The surface area of the sphere expands proportionally to
> R^2. Therefor, the law of conservation of energy dictates that the
> energy received over a constant area receiver (say, a 1 cm^2 energy
> receiver) will decline proportionally to the square of the distance
> from the transmitter.
>
> As a side note - does that prove that our universe only has three
> dimensions?
>
> However, if our transmitter is directional, and you keep the
> transmitter beam focused, so that it does not expand, there is no
> reason for the energy to almost not discard at all. Of course, the
> medium through which you transmit the energy may absorb some of it
> (assuming it is not a vacuum), and it may disperse some more of it,
> but there is no reason to get 1/R^2, or even 1/R.
>
> Shachar
> -- 
> Shachar Shemesh
> Lingnu Open Source Consulting Ltd.
> http://www.lingnu.com
>   

-- 
Sincerely yours,
Michael Vasiliev