Re: [Discuss-gnuradio] CIC decimator in software

[J.D. Bakker]

> I'm looking for opinions about whether doing a single-stage, N=2 
> decimator in software is practical for
>   sample rates of ~100Msps.  Assume reasonably-modern X86-64 
> hardware, and R=[2..500].

Assuming you can get the data into the processor fast enough, I 
expect you will.

(As a reference point: a decade ago I wrote a fourth order fixed 
point Bessel filter as a speedtest for my StrongARM-based SDR 
platform, with 16bit input, 32bit coefficients and 64bit accumulator. 
After a minor fixup to make it 64-bit clean, it shows a throughput 
of >290Msps (fixp) / >275Msps (floatp) on my vanilla Core i7-920.)

Good luck,

JDB.
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