interpolation in DAC and interpolation in multirate signal processing

[rameshbalan]

i have one doubt. what is the difference between interpolation filter in DAC and interpolation in multirate signal processing. why the filter in reconstruction of DAC is called interpolation filter.

 

[jrwebsterco]

You are likely running into a terminology abuse situation.
The DAC output filters are more clearly referred to as reconstruction filters, so you already answered your own question in your post.

Take a look at this: https://www.dspguide.com/ch3/4.htm

 

[rameshbalan]

no, i am asking why this reconstruction filter is called interpolation filter?. is this interpolation and interpolation in the multirate signal processing are same or not? please tell.

 

[mathespbe]

reconstruction filter and interpolation filter are different. A reconstrunction filter smoothens the O/P wave form by means of step sizes where as interpolation filter smoothens the O/P waveform by means of over sampling...

 

[rameshbalan]

i understood,
but in oppenheim "signals and systems" second edition book page no 522, they are telling that interpolation is commonly used for reconstruction in discrete to continuous time converter

 

[mathespbe]

Basically reconstruction is the process of smoothening the O/P waveform. The process involved in reconstruction filter and intepolation filter only differs. The goal of both filters in ADC is the same. But actual application of interpolation filer is wide...

 

[rameshbalan]

thanks, now i understood the difference between the reconstruction filter and interpolation filter.