AVR-Chat

Javier -

Doing what you suggest is difficult. It is not difficult to
measure signal strength (of many signals, including radio).
The problem is that, at almost all frequencies (from audio
to light) there are reflections that result in constructive
or destructive interferance. Light tends to be less
susceptable because of the short wavelength. You could use
a light source (LED) and pulse it. The pulse signature
could be used to separate the desired signal from the
background (ambient). But, sensing the signal over a wide
field of view isn't so easy.

Just an idea. Maybe others will have more suggestions.

Jim

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