Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!apple!netcom!mcmahan
From: mcmahan@netcom.UUCP (Dave Mc Mahan)
Newsgroups: comp.dsp
Subject: Re: Using system ID for FIR filter design?
Message-ID: <16486@netcom.UUCP>
Date: 9 Nov 90 05:07:42 GMT
References: <4973@tekfdi.FDI.TEK.COM>
Organization: Dave McMahan @ NetCom Services
Lines: 31


 In a previous article, kyleb@tekfdi.FDI.TEK.COM (Kyle Bernard) writes:
>I am beginning to look into using system identification techniques
>for FIR filter design.  Specifically, I want to use system ID to develop
>a digital FIR filter whose response matches that of an existing analog
>bandpass filter.

I'm not sure I quite understand your usage of the term 'system ID'.  From
what you describe, it sounds like you mean 'impulse response'.  Is this true?
Given an impulse response for any linear time invariant system, you can
directly create an FIR filter very simply and mechanically.  Impulse response
of a system is derived by one of several means.  I personally like to
stimulate the circuit to be copied with an impulse.  This is normally a
pulse of very short duration with respect to the system being analyzed.
'Short duration' is sort of defined by the system under test.  It could be
1 second or 1 picosecond depending on the system.  Recording of the output
of the system yields the impulse response directly.  This process can also
be done using a step function and various other known signals.  The recorded
response must then be post-processed to yield the impulse response.  Is this
what you are wanting to know about?

>Kyle.

>uucp:	    tektronix!tekfdi!honda!kyleb

     -dave


-- 
Dave McMahan                            mcmahan@netcom.uucp
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