In RF, there is something called "capture effect" in which you can tell one
signal over another just by "capturing" the one with higher amplitude and
discarding the other.

You mentioned that the background interference signal is of smaller
amplitude than the reference signal, so you may be able to use the capture
effect.

You also mentioned that the reference signal occurs "infrequently" and lasts
about 1/2 sec. Does this mean that it is not periodic? If this is the case,
then the problem is much harder, because you cannot "predict" when the next
signal will occur.

I hope this helps!

Regards,
Andres Tarzia
Technology Consultant, SMART S.A.
e-mail: atarzia@smart.com.ar

-----Original Message-----
From: adastra [mailto:foster@ADASTRAN.COM]
Sent: Friday, April 09, 1999 21:38
To: PICLIST@MITVMA.MIT.EDU
Subject: Extracting a Doppler signal in the presence of noise

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