> A decent size CRC is also important so that random noise or partially
> corrupted real messages get properly discarded. =A0The indoor location sy=
stem
> I mentioned uses a 20 bit CRC.

That's commendably long.
How many bits per transmission?
Dim stirrings from back of brain suggests that you'll catch all one
bit errors for total block length under 2^CRC_bits bits long. Just
attempted to mentally derive maximum block length with no undetectable
errors for X CRC bits and Y error bits max but didn't believe result.

eg either ~ 2^(X-Y) max block length - seems too good.
or ~ 2^(X - 2^Y) seems a bit harsh.
Later ...

Might not you be able to use some FEC with that much room available
for error control?


   Russell

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