> Algorithm:
>         Pulse HIGH!     ; LED ON.
>         Read ADC        ; Result A = Signal + Noise
>
>         Pulse LOW!      ; LED OFF.
>         Read ADC        ; Result B = Noise
>
>         SUB A-B ; Result C = (Signal+Noise) - (Noise)
>
>         C = pure signal strength.
>
> This has proven to work well for distances up to 8 inches using an 8-bit
> ADC. This is the first time I'm trying to extend the range, with a more
> sensitive sensor and a 12-bit ADC.
>
> Is there a better algorithm of filtering which would provide greater
> results? A better sensor, or maybe a better method to the entire
> project. I have played with Sharps' GP2D02 module as well; and have
> gotten rather unsatisfactory results. If the current method cannot be
> improved upon, then my next step is to try one of those 40 khz
> Sharp IR modules. They won't give me proximity ranging, but
> maybe reliable object detection; and atleast that's a start.

What I would add is an AGC circuit. Do the switching faster
than the time constant of the AGC circuit, and you should
have more sensible readings.

--
Friendly Regards           /"\
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Tjaart van der Walt         X ASCII RIBBON CAMPAIGN
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