> > Is this the same baseband signals copied at several place ? > It is yes.
What you can do is : > > * First modulate the signal to a narrow sample-rate (just enough for > the modulation) > > * Upsample that signal to 1 Msps. > - Depending on the ration between the narrow rate and wide rate, it > might be > beneficial to do that in several steps. > - So for instance you would go from 10 kHz to 100 kHz first with a > filter that's relatively sharp > - Then you would go from 100 kHz to 1 MHz with a second filter than > can be much more relaxed (i.e. larger transition bandwidth and so much > less CPU usage) > > * Then use several rotators to position it at the various places you > need it in the 1MHz bandwidth > > * And finally add the output of all the rotators. > Thanks for the suggestion. I'll give that a go. There is also the so called Polyphase Filter Banks, but that only > works if you need carriers that are all equally spaced. And is also > only a benefic if you really fill a significant number of them. In my case the output channels are arbitrary, so your first suggestion sounds like the one I need to implement. Thanks for taking the time to respond.
