1. You neglected to say what the important parameters are which you want
to abstract from the collected data!
2. Some cetaceans and other sources go to at least 150 KKz.
3. You neglected to indicate the phase response you will need nor the
error between the two channels in phase and amplitude.
4. The original purpose of Fourier methods was to look at what happens
inside a KNOWN boundary NOT I repeat NOT to determine the values of a
boundary. There are many errors to be expected in the results of
frequency determinations using any of the current FFT methods. For
single input frequencies to a FFT frequency errors of 10% have occured.
Phase errors also occur!
5. The current best A/D converter (which I would use) is only 14 bits.
It is the ANALOG DEVICES AD10465 A DUAL CHANNEL 14 BIY 65 MEGA-SAMPLES
PER SECOND converter. I would use (if possible) IEEE 1394 VERSION 2.
version 1 is not as fast as USB 2. There is an evaluation board
available for the 10465 which I would recommend be incorporated into
your front end.
6. For those interested in how to evaluate the output of an FFT (being
used for frequency determination) routine let me know and I will post
examples of pathologic cases.
FRED
--
Fred Herzfeld, MIT'54
78 Glynn Marsh Drive #59
Brunswick, Ga. 31525-0504
USA
Tel: (912) 262-1276
Fax: (912) 262-1276 by request
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