ADS Rectifier Simulation

Here is the example of rectifier but I can not see half wave sine as output voltage . How should I analyse the circuit? I have tried with AC Simulation , Transient Simulation. Pls help me, since 2 weeks i am trying to find out.

The correct engine you have to use is transient. It performs a non-linear time-domain simulation.
Tha AC analysis is instead a linear analysis in the frequency domain: the generator sweeps the frequency range you choose. A frequency is generated and the ouptut is calculated at that frequency, then the generator is moved to the next frequency and the measurement is repeated and so on, until the whole range is swept.
However the diode will cut the voltage lower than its knee-voltage (roughly 0.7V or 0.4 in case of schottky barrier). From your schematic you add a DC voltage of 1V to a sinewave of 1V amplitude, then the signal reaching the diode will range from 0 to 2V. Only a small part of the sinewave, and not a half wave will be cut-off. You should increase the singnal amplitude or reduce the DC voltage. If you have in mind a biased RF power detector you have to bias the diode by means of a small current, not by means of a voltage.
Of course the diode must be fast enough with respect to your working frequency.