Subject: [AUDITORY] seeking old Kaiser paper From: "Richard F. Lyon" <dicklyon@xxxxxxxx> Date: Mon, 29 Jan 2018 20:15:04 -0800 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>--94eb2c1afccc76ca9c0563f69bfb Content-Type: text/plain; charset="UTF-8" Does anyone have the 1963 Proceedings of the First Allerton Conference on Circuit and System Theory? Or just "Design methods for sampled-data filters" by J. F. Kaiser? I'm trying to resolve a disconnect in derivations of the impulse-invariance method, which was "corrected" in several places over the years, though Kaiser had the key to the correction in his chapter "Digital Filters" in the 1966 "System Analysis by Digital Computer" book, in which he says his stuff on IIR design closely follows that missing paper as well as a BSTJ paper that does not have the key piece. The key observation is that using the naive impulse invariance method adds a constant (frequency independent) term to the frequency response of the digital filter proportional to the impulse response on the right side of time zero: T/2 * h(0+). He didn't go as far as the "corrections" which said to take the impulse response h[k] at k = 0 to be (h(0-) + h(0+))/2, though it's pretty obvious from there. It's funny that at some point he got as far as including that unwanted term yet didn't comment on the easy way to remove it. Maybe in the missing paper... Dick --94eb2c1afccc76ca9c0563f69bfb Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable <div dir=3D"ltr"><div><div><div>Does anyone have the 1963 Proceedings of th= e First Allerton Conference on Circuit and System Theory?=C2=A0 Or just &qu= ot;Design methods for sampled-data filters" by J. F. Kaiser?=C2=A0 <br= ><br></div>I'm trying to resolve a disconnect in derivations of the imp= ulse-invariance method, which was "corrected" in several places o= ver the years, though Kaiser had the key to the correction in his chapter &= quot;Digital Filters" in the 1966 "System Analysis by Digital Com= puter" book, in which he says his stuff on IIR design closely follows = that missing paper as well as a BSTJ paper that does not have the key piece= .=C2=A0 <br><br></div>The key observation is that using the naive impulse i= nvariance method adds a constant (frequency independent) term to the freque= ncy response of the digital filter proportional to the impulse response on = the right side of time zero: T/2 * h(0+).=C2=A0 He didn't go as far as = the "corrections" which said to take the impulse response h[k] at= k =3D 0 to be (h(0-) + h(0+))/2, though it's pretty obvious from there= .=C2=A0 It's funny that at some point he got as far as including that u= nwanted term yet didn't comment on the easy way to remove it.=C2=A0 May= be in the missing paper...<br><br></div>Dick<br><br><div><div><br></div></d= iv></div> --94eb2c1afccc76ca9c0563f69bfb--