Hi group! Can someone help me with how phase-noise through a mixer is calculated? Let's say I connect a 1 GHz signal with -80 dBc/Hz PN (wrt. 1GHz carrier) at some offset to the RF port. I then connect a 900 MHz signal with also -80dBc/Hz PN (wrt. 900MHz carrier) at the same offset. I'm interested in the 100 MHz IF signal (naively, will it have -77 dBc/Hz PN wrt 100MHz? carrier?) (ofcourse there might be a noise-figure through the mixer also) thanks! Anders

		Attila Kinali

On Mon, 17 Oct 2016 23:45:23 +0300 Anders Wallin <anders.e.e.wallin@gmail.com> wrote: > Can someone help me with how phase-noise through a mixer is calculated? Have you had a look at Enrico Rubiola's mixer tutorial[1]? I think it contains all you need for noise calculation. Attila Kinali [1] http://rubiola.org/pdf-articles/archives/2006-arxiv-0608211v1-mixer-tutorial.pdf -- Malek's Law: Any simple idea will be worded in the most complicated way.

Hi Simple answer is yes. More complex answer gets into things like the noise of the mixer (not just it’s floor), the levels of the signals, noise being coherent rather than non-coherent, AM <-> PM conversion and on and on …. Bob > On Oct 17, 2016, at 4:45 PM, Anders Wallin <anders.e.e.wallin@gmail.com> wrote: > > Hi group! > > Can someone help me with how phase-noise through a mixer is calculated? > > Let's say I connect a 1 GHz signal with -80 dBc/Hz PN (wrt. 1GHz carrier) > at some offset to the RF port. > I then connect a 900 MHz signal with also -80dBc/Hz PN (wrt. 900MHz > carrier) at the same offset. > I'm interested in the 100 MHz IF signal (naively, will it have -77 dBc/Hz > PN wrt 100MHz? carrier?) > > (ofcourse there might be a noise-figure through the mixer also) > > thanks! > Anders > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.

Mixers also have the curious phenomenon of non-reciprocity On 10/17/2016 4:13 PM, Bob Camp wrote: > Hi > > Simple answer is yes. > > More complex answer gets into things like the noise of the mixer (not just it’s floor), > the levels of the signals, noise being coherent rather than non-coherent, AM <-> PM > conversion and on and on …. > > Bob > > > >> On Oct 17, 2016, at 4:45 PM, Anders Wallin <anders.e.e.wallin@gmail.com> wrote: >> >> Hi group! >> >> Can someone help me with how phase-noise through a mixer is calculated? >> >> Let's say I connect a 1 GHz signal with -80 dBc/Hz PN (wrt. 1GHz carrier) >> at some offset to the RF port. >> I then connect a 900 MHz signal with also -80dBc/Hz PN (wrt. 900MHz >> carrier) at the same offset. >> I'm interested in the 100 MHz IF signal (naively, will it have -77 dBc/Hz >> PN wrt 100MHz? carrier?) >> >> (ofcourse there might be a noise-figure through the mixer also) >> >> thanks! >> Anders >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > >