how to find impedance of a rectifier circuit in ADS

I have a RF rectifier circuit in ADS. I want to match the power source impedance to the rectifier impedance. In order to do that and to use Smith Chart utility, I need to know the impedance of the rectifier circuit. How can I find it using ADS? I know my power source impedance to be 50 ohms. Please tell me how to do it and I am a total beginner in ADS. Thanks

Rectifier impedance is a large signal property. Use harmonic balance analysis to derive it.