Re: [Discuss-gnuradio] rational_resampler vs pfb_arb_resampler filter design -- why such strange cut frequencies in both cases?

[Lev Serebryakov]

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On 23.10.2014 01:39, Lev Serebryakov wrote:

> (1) Why rational resampler doesn't take decimation in account when 
> calculates bandwidth? It design filter which will correctly reject
> all images in upsample, but looks like aliasing is possibly when
> effective ratio is less than 1, as only interpolation is used in
> bandwidth calculation and resulting filter "effectively" works at
> upsampled rate.
 Here I'm right, according to other thread.

> (2) Why arbitrary resampler set Fs to number of filters and AFTER 
> that pass bandwidth numbers as normalized to 1, not to this Fs?!
> 0.3 is perfectly good (may be slighly conservative, but Ok)
> transition band center, but in this case this 0.3 will be taken for
> FS=1, and here FS=32 (number of filters) is used, so it will be 32
> times too low (!).
 And here I'mn wrong, and code is right, as filter effectively work
and "higher" frequency and all frequencies should be properly scaled.

- -- 
// Black Lion AKA Lev Serebryakov
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