Hi Frank thanks for Your hints.
I think I reconstruct my HDR-2005 to a simple SDR-2005 with SDRadio software... My latest version of the HDR-2005 looks like http://www.snopes.com/inboxer/images/rand.jpg ;-) Chris --- In [email protected], "Frank Eory " <[EMAIL PROTECTED]> wrote: > > Chris, > Maybe you can try a purely analog demodulation using this inequality > sqrt(i^2 + q^2) >= max ( abs(i), abs(q)) > > The max can be done with an op amp comparator circuit, comparing the two > voltages and selecting an analog multiplxer for the output. > > For the abs(x), I suppose that one can just compare the x with 0 and > have the op amp select x or -x, where the later comes from an unity gain > inverting amplifier. > > All of this would take 5 op amps and three multiplexers. > > Another math inequality which may work for AM demodulation is: > sqrt(i^2 + q^2)<= abs(i) + abs(q) > > It would be best to try these out in Matlab or C, measure the SNR before > trying the circuits. > Frank > ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/ELTolB/TM --------------------------------------------------------------------~-> 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/
