Hi all
I do agree. We are routinely doing 16 million channels FFT using
ROACH2+GPU (note you need a 6giga GPU memory to to this), basically to
track RFI. The fact GPU works in floating point simplifies greatly the
design, since you end with huge narrow features. Not easy to deal with
in
hi molly,
regarding making a large FFT from small FFT's:
as jason pointed out, there's a way to compute a million point spectrum
from lots of small FFT's.
the technique jason described is to implement a course channelization
polyphase filter bank spectrometer to divide the band into 1024 sub-band
On FPGAs, ~million channel spectrometers are typically built by doing a 1024ch
PFB, followed by a matrix transpose (to collect 1024 samples of a single
channel together) and another FFT. Mostly, you'll find you run out of memory if
you try to do a million-channel FFT directly on an FPGA.
There
Hi Molly,
There is an old tutorial with a million channel spectrometer up here:
https://casper.ssl.berkeley.edu/wiki/Old_Tutorials
This was on the ROACH1, and used a 1024-point real FFT, a 1024x1024
transpose using QDR RAM, followed by a second 1024-point complex FFT.
If you have access to a comp
Hello Molly,
We have done something broadly similar using ROACH2 and katADC, but only
1024 channels:
https://github.com/ska-sa/AVNRoachGateware/tree/master/WideBandSpectrometer
What frequency are you looking at? The only thing I'm thinking is that you
might struggle to get the design to meet timi
Hello,
I'm new to CASPER and am trying to implement a million channel spectrometer
on ROACH2 with the katADC. Does anyone know of any useful resources or has
done something similar?
I have experience using Vivado for newer FPGA development and am
comfortable with Verilog & VHDL. I'm not famil
6 matches
Mail list logo