Re: [Discuss-gnuradio] question about overruns with simple flowgraph

[Stephen]

On 8/6/2013 8:15 PM, Marcus D. Leech wrote:
> On 08/06/2013 09:07 PM, Stephen wrote:
>>> I tend to use the fractional interpolator--you can get exact rate
>>> matching that way.  It doesn't seem that expensive, particularly when I
>>> use it at the
>>>    "low speed" part of the graph near the audio subsystem.
>>>
>> I tried that and it worked. But it adds a small amount of hiss. I also
>> tried the fractional resampler. It added a lot of hiss and a high pitch
>> whine. The polyphase arbitrary resampler added a more hiss than the
>> fractional interpolator but less than the fractional resampler.
>>
>> stephen
>>
> If you're downsampling, you do need to make certain that the bandwidth
> of your incoming signal (regardless of its rate) is appropriate for
>   the final bandwidth after the resampler.
> 
> 
> 
so when is it more appropriate to use a rational resampler vs a
polyphase arbitrary resampler vs a fractional resampler vs a fractional
interpolator ?  Does the processing load differ grately between them?