How many taps does an iir filter have? TIA.
Taps
Started by ●October 23, 2005
Reply by ●October 23, 20052005-10-23
Jake wrote:> How many taps does an iir filter have? TIA.none -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●October 23, 20052005-10-23
in article 435BF765.66DB2BA3@ever.com, Jake at wh@ever.com wrote on 10/23/2005 16:49:> How many taps does an iir filter have? TIA.gee, i dunno. 40, i guess. maybe 1. depends on its order. also depends on whether it has zeros or not. gotta be more specific in framing the question. -- r b-j rbj@audioimagination.com "Imagination is more important than knowledge."
Reply by ●October 23, 20052005-10-23
robert bristow-johnson wrote:> > in article 435BF765.66DB2BA3@ever.com, Jake at wh@ever.com wrote on > 10/23/2005 16:49: > > > How many taps does an iir filter have? TIA. > > gee, i dunno. 40, i guess. maybe 1. > > depends on its order. also depends on whether it has zeros or not. > > gotta be more specific in framing the question.I've read somewhere that the number of taps for an FIR filter is the order plus one (for the current input). Is this right? And can someone please answer the question for IIR? Again, thanks in advance.> -- > > r b-j rbj@audioimagination.com > > "Imagination is more important than knowledge."
Reply by ●October 23, 20052005-10-23
Jerry Avins wrote:> > Jake wrote: > > How many taps does an iir filter have? TIA. > > noneWhat do you call the stored inputs for output calculation? Google search, "iir taps" : 20 hits ( but no explanation :-( )> -- > Engineering is the art of making what you want from things you can get. > �����������������������������������������������������������������������
Reply by ●October 23, 20052005-10-23
in article 435C0D55.EC248FF3@ever.com, Jake at wh@ever.com wrote on 10/23/2005 18:23:> robert bristow-johnson wrote: >> >> in article 435BF765.66DB2BA3@ever.com, Jake at wh@ever.com wrote on >> 10/23/2005 16:49: >> >>> How many taps does an iir filter have? TIA. >> >> gee, i dunno. 40, i guess. maybe 1. >> >> depends on its order. also depends on whether it has zeros or not. >> >> gotta be more specific in framing the question. > > I've read somewhere that the number of taps for an FIR filter is the > order plus one (for the current input). Is this right?yup. i guess.> And can someone please answer the question for IIR?then, i guess it would be twice the order plus one. unless it's an all-pole IIR (no zeros), then it's the same as FIR, order+1.> Again, thanks in advance.FWIW. -- r b-j rbj@audioimagination.com "Imagination is more important than knowledge."
Reply by ●October 23, 20052005-10-23
"Jake" <wh@ever.com> wrote in message news:435BF765.66DB2BA3@ever.com...> How many taps does an iir filter have? TIA.I never understood the reason for calling it taps or tapped-delay line. To me it is just an equation - ditto for IIR. y(k)=-a1y(k-1)-a2y(k-2)+....-any(k-n) + b0u(k)+b1u(k-1)++...+bmu(k-m) why the need to know about taps - the equation is obvious. McC
Reply by ●October 23, 20052005-10-23
"Jake" <wh@ever.com> wrote in message news:435BF765.66DB2BA3@ever.com...> How many taps does an iir filter have? TIA.I smell a troll, but I'll play along. One way of implementing an IIR filter looks like this (switch to fixed-pitch font): Sum T Sum X--->O-----------+---------->O--->Y ^ | ^ |Multiply V |Multiply [-b] +-------------+ [a] | | unit delay | | | +-------------+ | | | | | V | +-----------+-----------+ In algebraic form: T_n = X_n - b*T_{n-1} Y_n = T_{n-1} + a*T_{n-1} How many taps do you think this IIR filter has?
Reply by ●October 23, 20052005-10-23
"John E. Hadstate" <jh113355@hotmail.com> wrote in message news:7JV6f.2746$NJ.1914@bignews7.bellsouth.net...> > "Jake" <wh@ever.com> wrote in message > news:435BF765.66DB2BA3@ever.com... >> How many taps does an iir filter have? TIA. > > > I smell a troll, but I'll play along. > > One way of implementing an IIR filter looks like this > (switch to fixed-pitch font): > > > Sum T Sum > X--->O-----------+---------->O--->Y > ^ | ^ > |Multiply V |Multiply > [-b] +-------------+ [a] > | | unit delay | | > | +-------------+ | > | | | > | V | > +-----------+-----------+ > > > In algebraic form: > > T_n = X_n - b*T_{n-1} >*** Correction ****> Y_n = T_n + a*T_{n-1}> > How many taps do you think this IIR filter has? > > >
Reply by ●October 23, 20052005-10-23
robert bristow-johnson wrote:> > in article 435C0D55.EC248FF3@ever.com, Jake at wh@ever.com wrote on > 10/23/2005 18:23: > > > robert bristow-johnson wrote: > >> > >> in article 435BF765.66DB2BA3@ever.com, Jake at wh@ever.com wrote on > >> 10/23/2005 16:49: > >> > >>> How many taps does an iir filter have? TIA. > >> > >> gee, i dunno. 40, i guess. maybe 1. > >> > >> depends on its order. also depends on whether it has zeros or not. > >> > >> gotta be more specific in framing the question. > > > > I've read somewhere that the number of taps for an FIR filter is the > > order plus one (for the current input). Is this right? > > yup. i guess.You guess? Is dsp a *science* or not? Do you have any idea how frustrating it is for a beginner to learn when the experts can't agree on basic definitions or want to play wordgames whenever someone asks a legitimate question? If this was in the FAQ, I wouldn't have to ask, but obviously the FAQ is deficient.> > > And can someone please answer the question for IIR? > > then, i guess it would be twice the order plus one. unless it's an all-pole > IIR (no zeros), then it's the same as FIR, order+1. > > > Again, thanks in advance. > > FWIW. > > -- > > r b-j rbj@audioimagination.com > > "Imagination is more important than knowledge."
