21-09-2018, 10:38 AM
Ought to work, so long as the up-converter is nicely linear.
The other way is a fully fledged VSB filter which is a lot more complicated than an off-the-shelf SAW. Darius designed a VSB filter for his modulator but this is all the data I have. Aligning a VSB filter accurately really needs a vector network analyser, something most of us don't have. The group delay matters a lot, so an ordinary frequency sweep or white noise test isn't really good enough.
We've discussed direct digital synthesis of RF, such as Fabrice Bellard's work. I wonder if that could do a decent job of VSB.
The other way is a fully fledged VSB filter which is a lot more complicated than an off-the-shelf SAW. Darius designed a VSB filter for his modulator but this is all the data I have. Aligning a VSB filter accurately really needs a vector network analyser, something most of us don't have. The group delay matters a lot, so an ordinary frequency sweep or white noise test isn't really good enough.
We've discussed direct digital synthesis of RF, such as Fabrice Bellard's work. I wonder if that could do a decent job of VSB.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
