is fir filter is benificial or the iir filter for the application to measure the total harmonic distortion in metering equipment. and also reasons to select particular filter, fir requires more memory than iir,, but iir is not a linear phase,,
about filters
Started by ●February 8, 2011
Reply by ●February 8, 20112011-02-08
On 02/07/2011 10:02 PM, rashmi venugopal wrote:> is fir filter is benificial or the iir filter for the application to > measure the total harmonic distortion in metering equipment. > and also reasons to select particular filter, > > fir requires more memory than iir,, but iir is not a linear phase,,Does linear phase matter if you just want to know power magnitude? FIR filters require memory in inverse proportion to their bandwidths, while IIR filters require memory in something like -A*log(bandwidth). What sort of bandwidth requirements do you think a total harmonic distortion analyzer requires? -- Tim Wescott Wescott Design Services http://www.wescottdesign.com Do you need to implement control loops in software? "Applied Control Theory for Embedded Systems" was written for you. See details at http://www.wescottdesign.com/actfes/actfes.html
Reply by ●February 9, 20112011-02-09
>On 02/07/2011 10:02 PM, rashmi venugopal wrote: >> is fir filter is benificial or the iir filter for the application to >> measure the total harmonic distortion in metering equipment. >> and also reasons to select particular filter, >> >> fir requires more memory than iir,, but iir is not a linear phase,, > >Does linear phase matter if you just want to know power magnitude? FIR >filters require memory in inverse proportion to their bandwidths, while >IIR filters require memory in something like -A*log(bandwidth). What >sort of bandwidth requirements do you think a total harmonic distortion >analyzer requires? > >-- > >Tim Wescott >Wescott Design Services >http://www.wescottdesign.com > >sir,, band width is 45 - 65 hz,, the memory less and also we need linearphase,, so if i use FIR filter then memory constraint,, is there any techniquie to adjust the memory usage so that we can implement FIR filter,,
Reply by ●February 9, 20112011-02-09
>On 02/07/2011 10:02 PM, rashmi venugopal wrote: >> is fir filter is benificial or the iir filter for the application to >> measure the total harmonic distortion in metering equipment. >> and also reasons to select particular filter, >> >> fir requires more memory than iir,, but iir is not a linear phase,, > >Does linear phase matter if you just want to know power magnitude? FIR >filters require memory in inverse proportion to their bandwidths, while >IIR filters require memory in something like -A*log(bandwidth). What >sort of bandwidth requirements do you think a total harmonic distortion >analyzer requires? > >-- > >Tim Wescott >Wescott Design Services >http://www.wescottdesign.com > >sir,, band width is 45 - 65 hz,, the memory less and also we need linearphase,, so if i use FIR filter then memory constraint,, is there any techniquie to adjust the memory usage so that we can implement FIR filter,,
Reply by ●February 9, 20112011-02-09
>On 02/07/2011 10:02 PM, rashmi venugopal wrote: >> is fir filter is benificial or the iir filter for the application to >> measure the total harmonic distortion in metering equipment. >> and also reasons to select particular filter, >> >> fir requires more memory than iir,, but iir is not a linear phase,, > >Does linear phase matter if you just want to know power magnitude? FIR >filters require memory in inverse proportion to their bandwidths, while >IIR filters require memory in something like -A*log(bandwidth). What >sort of bandwidth requirements do you think a total harmonic distortion >analyzer requires? > >-- > >Tim Wescott >Wescott Design Services >http://www.wescottdesign.com > >Do you need to implement control loops in software? >"Applied Control Theory for Embedded Systems" was written for you. >See details at http://www.wescottdesign.com/actfes/actfes.html >is fir filter is benificial or the iir filter for the application to measure the total harmonic distortion in metering equipment. and also reasons to select particular filter, as per the FIR uses more memory,, but the IIR uses less memory but it does not show linear phase response,, our metering equipment bandwidth is 45 - 65 hz, so now we have to implents the coefficients which we get from the filter design to the meters so that to measure total harmonic distortion,, now what to do,,, which filter to use,, This Message is Moderated
