jkreznar@ininx.com (John E. Kreznar) said:

Are you taking into account that as the power is dropped, coherent communication can compensate by dropping the data rate

Very low power transmitters are actually legitimate, at least in some bands, so you don't have to drop the signal to the point where it'd merge seamlessly with ambient noise. However I doubt that extremely low power transmitters will accomplish what is desired. I also wonder whether extremely low data rates are desired.

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There are other approaches...phase-sweeping...phase-conjugation... Do you have a reference for these? Neither appears in the index of any of the books in my spread-spectrum library. Maybe they're not spread-spectrum?

Different topic. Try "phase conjugate mirrors" in optical and physics journals. I'm not positive that this would be good enough to help avoid detection. Doug