Dan, I fully understand the memory limitations. Just to clarify, it was just a experiment on the capabilities of the Casper FFT library, not intended to actually implement on FPGA. What prompted me to do this experiment was a rumor that the Casper library could support multi-million point FFTs.
~Jason Zheng On Mon, Jul 27, 2009 at 9:09 AM, Dan Werthimer <[email protected]>wrote: > > hi jason zheng, > > as you probably know, > a 2^20 point FFT won't fit on an fpga, > as it requires 2^19 times 36 bits of memory. > > the largest single fft that we've ever used > on an FPGA is 2^15 points. > > to implement higher resolution spectrum analyzers > one needs to implement analysis in > two stages (course PFB, followed by fine FFT). for example > see the 128 million point spectrometer block diagram at > http://seti.berkeley.edu/jplsetispec/block_diagram.pdf > > > best wishes, > > dan > > > > Jason Zheng wrote: > >> Last time I tried this on 10.1 with a 2^20 FFT design, the Matlab froze >> for a long time and I ended up closing the program. >> >> On Mon, Jul 27, 2009 at 8:31 AM, Laura Spitler >> <[email protected]<mailto: >> [email protected]>> wrote: >> >> Hello everyone, >> >> What's the status of large green FFTs, where "large" is greater than >> 2^11? Can they now be reliably synthesized in 10.1? >> >> Thanks, >> Laura >> >> >>
