Well, if Dave, Glenn and Aaron all agree, then I'm sold. Thanks.
On Wed, Feb 21, 2018, 10:50 PM David MacMahon <dav...@berkeley.edu> wrote: > Hi, Jack, > > I haven’t used the biplex_core block in a while, but I believe the inputs, > pol1 and pol2, are two independent complex input signals. The outputs, out1 > and out2, first output the frequency channels for input pol1, with the low > half of the band being output in bit reversed order on out1 and the high > half of the band being output on out2 in bit reversed order. After > outputting the channels for pol1, out1 and out2 output the channels for > pol2 in a similar order. > > For a 16 channel fft, I think out1 will have channels: pol1[0 4 2 6 1 5 3 > 7] followed by pol2[0 4 2 6 1 5 3 7]. Out2 will have the same output order > but 8 (ie N/2) channels higher. I hope that makes sense, but if not I can > make a better diagram for you tomorrow. > > Of course this should be verified with simulation, but I think it’s a good > starting point. BTW, this assumes the inputs are presented in natural tone > order at both inputs with the t=0 samples of pol1 and pol2 being presented > at the respective inputs simultaneously. > > Dave > > On Feb 21, 2018, at 18:04, Jack Hickish <jackhick...@gmail.com> wrote: > > Howdy, > > Partly motivated by a search for RAM savings, and partly for fun, I'm > looking through the innards of the fft_biplex_real_4x block. Can someone > tell me, using short words and/or pictures, what the the relationship > between the inputs (pol1, pol2) and the outputs (out1, out2) on the > biplex_core block is. > > I'm in the midst of reverse engineering the block by simulation / staring > at the unscrambler / reading about fft biplex implementations, but surely > someone must(!) know what this block actually does (or claims to do)? > > Yours, optimistically, > > Jack > > -- > > You received this message because you are subscribed to the Google Groups " > casper@lists.berkeley.edu" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to casper+unsubscr...@lists.berkeley.edu. > To post to this group, send email to casper@lists.berkeley.edu. > > -- > You received this message because you are subscribed to the Google Groups " > casper@lists.berkeley.edu" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to casper+unsubscr...@lists.berkeley.edu. > To post to this group, send email to casper@lists.berkeley.edu. > -- You received this message because you are subscribed to the Google Groups "casper@lists.berkeley.edu" group. To unsubscribe from this group and stop receiving emails from it, send an email to casper+unsubscr...@lists.berkeley.edu. To post to this group, send email to casper@lists.berkeley.edu.
