How to optimize from ideal passive components to real-world discrete components?

Hello experts!

I've simulated a rectifier using ADS which operates at 2.45 GHz for turning on an LED. Later, this will be matched to a receiving antenna.
When I used ideal components from ADS library, the output voltage seems to be pretty solid.
However, when I replaced all the lumped elements with real discrete components, my output is too noisy.
I did expect some ripples, but the ripple peak to peak is over 300 mV.
Can you please take a look at my design and point me what i did wrong? Also, please check out my schematic setup. The 3 ohm resistor is just to simulate a lengthy wire. Without it, the output voltage is very weird.

Thank you very much for your help.

Check the self resonance frequency of your 1nF capacitor.

This is a half-wave parallel voltage multiplier. Contains several charge-pump stages. Each cycle a current spike travels through the capacitors. This might explain the solid red area in your graph (because cycles are numerous and close together).

Or else the led is the type of load which gobbles it's own spike of current per cycle. A diode is itself a voltage regulator. It's quick-acting.

It helps that you installed resistance at one or two places in the circuit. However this does not reduce all the spikes through the circuit. In addition try putting a low-ohm resistor inline with each capacitor. Then the charging and discharging waveforms are easier to observe.

I could be wrong. Often a solid area on a graph is created by parasitic oscillations (the kind which might occur in self-resonating components as suggested by post #2). Normally your circuit is not the kind that should produce oscillations. Since your frequency is in the Ghz range, then try lengthening the time axis, so it creates some white space between waveforms in the solid red area.

Both simulations show about 500 to 600 mV output. Likely at very low current.

Visible light LEDs generally have a forward drop of about 2V, and require about 5 mA to be bright enough to be useful.

I do not think your circuit will work.

22 gauge copper wire (0.644 millimeter diameter) has a resistance / length of 53 milliohm/meter.
Your 3 ohm resistor is equivalent to about 56 meters of 22 gauge copper wire. Is that what you intended?

I think the capacitors which you have been using are not convenient for RF signals.I recommend you to change them with RF ones because small package inductors/capacitors may affect the performance.