Talk:Reconstruction filter

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Is this in reference to CT reconstruction from DT samples?

[edit] Not anti aliasing

Its not to avoid aliasing, its to remove atrifacts of the digital signal--Light current 11:52, 22 December 2005 (UTC)

[edit] Ideal Reconstruction Filter

I think this text is misleading for the case of a DAC output with zero-order hold (i.e. stair stepping). In fact, a zero order hold has a frequency response equal to a sinc function with its first zero at the update rate of the DAC. At the Nyquist rate (update rate of the DAC / 2), the frequency response of the system as described is 2/pi or ~0.636. In order to correct, the ideal frequency response of the reconstruction filter should be 1/sinc with a brick wall at Nyquist. So, in fact, peaking is needed with a zero-order hold system in order to assure a flat passband performace.