An addendum to my info: >From this paper, I gave You the internet-adress, You can clearly see and take some consequences for receiver constructing.
1.1. If one has an oscillator with phase-noise, You not only mix the oscillator not only with the incoming frequency, but also with the phase-noise of the oscilltor. It is something like a synchronous mixing with a lot of frequencies and a lot of mixing products. The less the bandwidth of the phase-noise the better for quality of mixing result. 1.2. At mixing You mix a strong signal (the oscillator-signal) with a very little one, the incoming signal. Partly You have to filter the product. 1.3. You should avoid all solutions with phase noise inclusive solutions with ic-dividers. 1.4. The better the signal of the mixing process, the better the result. Because of that, to gain ultimate quality, You should forget a lot of solutions and change to a dds-circuit with a very high working-frequency. All other solutions have a lack of quality, to reach ultimate success. 1.5. The alternative could be a quartz-osciallator, but one is not able to change the frequency in a wider range. 1.6. My "feeling is" even concepts with I,Q-solutions could be better, if a fast dds-circuit is used. 1.7. Having a rectangular signal meens a lot of filtering.... and a lot of useless noise. One can see, that using a fast dds-circuit is at the moment even for traditional receveiver concepts in let me say AM, SSB and other modulation-types is "state of the art" and You miss-use time and effort for other versions. I will look for answers coming. In the meantime, I will work with my DRT1. An incoming signal is always not a digital one even, if its constructed digital by modulation as DRM. Wolfgang --- In [email protected], "Wolfgang Hartmann" <[EMAIL PROTECTED]> wrote: > > Hallo to all, especially to Dan. > > Here is an email adress, wher You can find some informations in german > language. > > http://www.elexs.de/clock3.htm > > You see the phase-noise and the noise carpet of several designs. > > They have a lot more on DRM, Elektor-receiver. > > Wolfgang > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/soft_radio/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
