Re: [Discuss-gnuradio] USRP2 Filtering/Decimation Question

[Bruce McGuffin]

Matt Ettus wrote:
> Bruce McGuffin wrote:
>   
> > Hi
> >
> > When I specify a particular receiver decimation rate
> > for the USRP2, the task of decimating is presumably
> > split up between the CIC and two half-band filters.
> > My question is how is the task split up,
> > and where in the code does this happen?
> >     
>
> If the requested decimation rate is a multiple of four, we use the two 
> halfband filters, and the rest is CIC.  If it is only a multiple of two, 
> we use one halfband filter and the rest in CIC.  If it is an odd number, 
> we use only CIC.
>
> Matt
>   
When the decimation rate is divisible by 2 but not 4, which half-band 
filter do you use?
And where in the code is this decision made?

Bruce