Re: [Discuss-gnuradio] halfband in CVS

[Lamar Owen]

> On Tue, Oct 25, 2005 at 12:16:09AM -0400, Lamar Owen wrote:
>> On Monday 24 October 2005 22:19, Eric Blossom wrote:
>> > Matt's been hard at work on the halfband filter for the FPGA, and it's
>> > in pretty good shape.  As long as you're not using a decimation factor
>> > of 10, everything looks good.  The FPGA code along with the relevant
>> > host side mods are checked in.
>>
>> Very cool.

>> I will attempt to try this out tomorrow on the PARI pulsar system, since
>> it is
>> currently tracking CVS, and the FFT curves are well characterized
>> against the
>> passband of the frontend there, and I know the hot-cold difference,
>> passband
>> shape, etc really well at this point.

> Good.  Let us know how it goes.

With a decimation rate of 8 and a DDC center frequency at 10.7MHz, I see
better than -10dB at the band edge now, which is a greater than 20dB
improvement in flatness.  Very nice.

Burning in now.  CVS pull as of thirty minutes ago and the RBF you posted
yesterday evening.
-- 
Lamar Owen
Director of Information Technology
Pisgah Astronomical Research Institute
1 PARI Drive
Rosman, NC  28772
(828)862-5554
www.pari.edu