plz help me,,ADS 2009 made me,crazy cant simulate the simple voltage multiper circuit

i designed the simple voltage multiplier circuit on ads 2009 simulator but unlucky i cant see the correct output

i used an ac voltage source and transient simulation ,, the output is constant at zero !
plz any one can help me ?

With a real diode model, the output will be a half wave of a few 10 mV. But apparently you managed to place a diode model without any default parameters, so the output may be exactly zero.

thnx for your reply but indeed i use this circuit as a practice for the main circuit .. my main project is to harvest rf power and convert it to dc power to used for charging the mobile battery ,, so we use shottky diode hsms 2852 as a rectifier instead of regular diode due to it's small turn on voltage .. the same problem happens , i think there is anther issue

Yes, it's a rather trivial problem I didn't recognize at first sight . V_AC has no output in transient analysis, use VtSine instead. You should also consult the simulation manual about reasonable MaxTimeStep values.