You are correct to a point.  Loads of forward error checking (fec)
algorithms are used to make a digital signal more robust.  The RF
environment is an extremely hostile place for digital signals.  Now given
this forward error correction, the processor speed, and other factors there
will always be a bit of a small delay in the communications.  If you want a
demo just call your land-line phone from your cell and observe the delay.
Just my technological two cents.

Dave Marthouse N2AAM
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