I had trouble understanding how the fft module works before, but now I understand. Therefore, the content expressed is very messy and takes up your time. I am very sorry.
在2023年4月12日星期三 UTC+8 00:47:14<Wang> 写道： > Hi CASPER, > > I've recently been designing the Corner Turner module.Converts the data > shape from [input channel, frequency] to [frequency, input channel]. > > My understanding of FFT module is not enough, especially the relationship > between data and frequency points. > > fft_biplex_real_2x block:Fft biplex real 2x - Casper (berkeley.edu) > <https://casper.astro.berkeley.edu/w/index.php?title=Fft_biplex_real_2x&oldid=7999> > > This is my understanding of fft_biplex_real_2x block: The FFT of the real > number input will generate complex numbers, but with a Hermitian symmetry > on the Fourier components, i.e. the negative frequency part is just the > complex conjugate of the corresponding positive frequency component, only > half of the complex numbers are independent. To avoid wasting memory and > data transportation, the input data block of two input channels are > combined as the real and imaginary components respectively to form a > complex input, and then FFTed together. > > An EQ module is placed between FFT module and Transpose module. > > I don't think I understand the 'frequency point' enough, so the following > question may itself be wrong. > > My question is: > 1.The fft_biplex_real_2x block sets fft size = 2^11. Its two outputs can > be viewed as the output of four real streams, each containing 1024 > frequency points. Is that right? > > 2.I designed 4 transpose modules, each responsible for a quarter frequency > point of 1024. Each module corresponds to a 10gb module that packages and > outputs the data. > > I'm curious, the fft output contains 1024 frequency points.How to divide > the real stream containing 1024 frequency points? Examples: > transpose_1:0-255, transpose_2:256-511, transpose_3:512-767, transpose: > 768-1023. > > Does anyone know the F-engine design article? It is better to have fft and > cornerturn module design ideas, I would like to read it! > > I really hope someone can communicate with me, I would appreciate it! > > BW! > Wang > -- You received this message because you are subscribed to the Google Groups "[email protected]" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/a/lists.berkeley.edu/d/msgid/casper/7a5dbeeb-5012-4f65-bd0c-86cef0825c44n%40lists.berkeley.edu.
