hi nimish, this could be a sync pulse problem???
how often do you inject a sync pulse? did you check the re-order block in your fft to figure out the minimum period sync pulse that's allowed for that particular FFT? the casper memo on sync pulse generation has info on this. dan On Fri, Mar 15, 2013 at 12:14 PM, Nimish Sane <nimish.s...@njit.edu> wrote: > Hi all: > > I am attaching a plot for Power of two inputs vs frequency channels. As > can be seen, we have this persistent problem where some channels at the end > just do not make any sense. We suspect that there is something going wrong > in the FFT block. Has anybody seen such behavior before or can think of > what may be going wrong? > > Following are some specifications that may be useful: > Hardware: ROACH2 with KATADC. > ADC Clock: 800 MHz, > FPGA clock: 200 MHz > Toolflow: XSG 11.5 with Matlab 2009b with RHEL5.8 > Libraries: SKA > FFT green block: fft_wideband_real > FFT size: 2^13 (4096 Output channels) > > Thanks, > > Nimish > -- > Nimish Sane > > Center for Solar-Terrestrial Research > New Jersey Institute of Technology > University Heights > > Newark, NJ 07102-1982 USA > > Tel: (973) 642 4958 > > Fax: (973) 596 3617 > nimish.s...@njit.edu >
