On Tue, 3 Feb 2009, Jason Manley wrote:
ASTRO lib won't work with the 9.1 tools :-(
7.1 will only work with Matlab R14 :-(
Ookay :-/
If you want to feed the 1:4 demuxed ADC data directly into the PFB_FIR, then
you need the wideband version. You'll notice in the Medicina packetised F
engine that we're using a DDC up front which extracts 1/4 of the band (hence
only one complex input to the PFB_FIR).
Yep. I was kind of wondering about that DDC part.
Are you trying to do an FFT on a real-sampled signal (in this case pick the
pfb_wideband_real and set the number of simultaneous inputs to 2^2 and feed
in the four real signals from the ADC),
Is the pfb_wideband_real found in the beta/devel mlib_devel_10_1 for
10.1i?
Does it work on the iBob?
or are you doing complex sampling on
the ADC's Q/I inputs with a 90deg out of phase clock sampling each input?
There are different versions of the PFB_FIR for each situation.
Just trying something really simple for starters.
Get the real-sampled 512Msamp/sec "I" input signal that is spread to
i0..i3. Low- or bandpass-filter with a 31/32-tap 4:1 decimating FIR in
polyphase decomposition. The Xilinx DAFIR v9.0 compiler supports multirate
decimating FIR with a single input, but not parallel/polyphase -- so i
used four xilinx fir blocks plus adders to accomplish this now.
The closest from the interface point of view is the Casper
/downconverter/dec_fir but I realize now that it is 2-tap only.
And PFBs/pfb_fir_real would do the job if I'd extract the desired band(s)
from the output after the filterbank output cornerturn. Too bad the PFB
doesn't work in our tool versions :-/
(I tried casper 8.2 for our Xilinx 9.1i but the required
xlUpdateModel('casper_library') causes Matlab to segfault after a few
minutes of running)
We managed to get the Xilinx 10.1i today for free.
If the pfb_wideband_real is found in the 10.1 casper i'll try it out
tomorrow. Maybe things wont crash over there in 10.1 ... ;-)
- Jan
