Re: [casper] wide_band_real fft simulation problem of tut3
Can I add to this - do you simulate a sync pulse input, and wait an adequate time to see it show up on the block output? Jack On 2 Nov 2014 12:50, "G Jones" wrote: > When you are simulating, do you have the fftshift set appropriately? A > pure sine wave will be the worst case for bit growth and overflow, so > you'll want an fftshift of 0x I think. > On Nov 2, 2014 2:11 AM, "Wang Jinqing" wrote: > >> Hi, >> >> I can run the tut3.mdl,but I found the simulation result of wide_band >> fft is not correct. For example I have generate a sine (freq= 1/4pi)wave >> input the KaADC ,I found the polyphase output sine wave is still ok on the >> scope, but after the wide_band_real fft ( after real and image parts >> seperation) and power I even can't find the corresponding spectrum line. >> There're many messy signals on the spectrum. It seems that the fft core not >> works well in simulation. Does someone run into this problem? >> >> Best Regards. >> >> Oliver Wang. >> >> >> >>
Re: [casper] wide_band_real fft simulation problem of tut3
When you are simulating, do you have the fftshift set appropriately? A pure sine wave will be the worst case for bit growth and overflow, so you'll want an fftshift of 0x I think. On Nov 2, 2014 2:11 AM, "Wang Jinqing" wrote: > Hi, > > I can run the tut3.mdl,but I found the simulation result of wide_band fft > is not correct. For example I have generate a sine (freq= 1/4pi)wave input > the KaADC ,I found the polyphase output sine wave is still ok on the scope, > but after the wide_band_real fft ( after real and image parts seperation) > and power I even can't find the corresponding spectrum line. There're many > messy signals on the spectrum. It seems that the fft core not works well in > simulation. Does someone run into this problem? > > Best Regards. > > Oliver Wang. > > > >
[casper] wide_band_real fft simulation problem of tut3
Hi, I can run the tut3.mdl,but I found the simulation result of wide_band fft is not correct. For example I have generate a sine (freq= 1/4pi)wave input the KaADC ,I found the polyphase output sine wave is still ok on the scope, but after the wide_band_real fft ( after real and image parts seperation) and power I even can't find the corresponding spectrum line. There're many messy signals on the spectrum. It seems that the fft core not works well in simulation. Does someone run into this problem? Best Regards. Oliver Wang.
