Hi Jonathan
That's a great paper, thanks.
There aren't any other SMA memos yet, right?
Gerry
On 8/25/2012 7:45 AM, Jonathan Weintroub wrote:
Hi Gerry and Jon,
This memo gives a quantitative analysis of multiplier, adder and memory
utilization for the F engine
https://www.cfa.harvard.edu/twiki/pub/SMAwideband/MemoSeries/sma_wideband_utilization_1.pdf
Some recent optimizations are not taken into account, however it is still valid
by and large.
The link should be freely accessible from anywhere on the net but if you have
trouble, let me know, or if you have any other questions.
Cheers,
Jonathan
On Aug 24, 2012, at 7:07 PM, Gerry Harp wrote:
Hi Dan
Your numbers look somehow backwards.
Did you mean:
32 inputs at 8K
16 at 4K
8 at 2K
4 at 1K?
Presumably, by narrowing the input bandwidth could permit proportionally
smaller channels at the output? So at 2.5 MHz input one could do 1 Hz channels?
Trying and compiling is the right thing to do. Hopefully we can arrange to do
this pretty soon.
Gerry
On 8/24/2012 8:55 AM, Dan Werthimer wrote:
hi john,
to get a real number, it would be best to compile the design .
you can re-compile zaki's octal F engine designed for roach I
(8 inputs at 250 Msps), or Hong's F engine (32 inputs at 250 Msps,
designed for roach II).
rough guess: you can get 32 analog inputs at 1K channels,
or 16 analog inputs at 2K channels, or 8 analog inputs at 4K channels,
or 4 analog inputs at 8K channels.
best wishes,
dan
On Fri, Aug 24, 2012 at 7:54 AM, Jon Richards <[email protected]> wrote:
All,
I need some advice. We are looking into developing an FX correlator using the Roach2 s as the
"F" and GPUs as the "X".
We will have 4 inputs to the Roach2 ADCs, at 250Msamples/sec, 8Gb/sec flowing
out to the X boards. How many channels should the Roach2 be able to process?
How would I guestimate that?
Any ideas appreciated!
Thanks,
Jon Richards
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Gerald R. Harp, Ph.D.
Director, Center for SETI Research
SETI Institute
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Gerald R. Harp, Ph.D.
Director, Center for SETI Research
SETI Institute
