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Simulators >> Circuit Simulators >> forward power measurement in spectre
https://designers-guide.org/forum/YaBB.pl?num=1235497885

Message started by tempora123 on Feb 24^th, 2009, 9:51am

Title: forward power measurement in spectre
Post by tempora123 on Feb 24^th, 2009, 9:51am

Hello,

I would like to TRAN simulate a circuit applying a waveform with fixed forward power and sweep the frequency of this waveform. I know the input impedance of the circuit but it is frequency dependent. Therefore, I have a question if this setup is possible in spectre? And how to measure forward power applied?

Thank you for your suggestions.

Title: Re: forward power measurement in spectre
Post by pancho_hideboo on Feb 25^th, 2009, 4:57am

I can't understand meaning of your question.

tempora123 wrote on Feb 24^th, 2009, 9:51am:

I would like to TRAN simulate a circuit applying a waveform with fixed forward power and sweep the frequency of this waveform.

What do you mean by forward power ?

If you mean decomposition of power to incident and reflected power, incident power is equivalent to available power of Signal Generator(=port in EDA Tool).

By using actual instruments such as Signal Generator, Directional Coupler, Power meter, etc., show maesurement diagram you want to emulate in EDA Tool.

http://www.designers-guide.org/Forum/YaBB.pl?num=1235554986/0#0
It seems that you don't understand incident(forward), reflected(reverse) powers and power dissipated in load and very basic RF common sense.

Pdis=Pinc-Pref=Pinc*(1-abs(Gamma)**2)

Here
Pinc=incident(forward)Power=Available Power,
Pref=reflected(reverse) Power,
Pdis=power dissipated in load or terminal power(power delivered to load),
Gamma=Voltage Wave Refelection Coefficient.

Power setting value of actual Signal Generator or Port in EDA Tool is incident power, that is, available power. It is not Pdis.

How do you define Pdis in transient analysis ?
Even though you use single tone sinusoidal drive, voltages and currents at terminal of load are never single tone.
So it is fairly difficult to keep constant value of Pdis for any frequency and any load.
But it is possible. At least you can do it by Cadence Spectre if you have correct and wide RF knowledge.

Title: Re: forward power measurement in spectre
Post by tempora123 on Feb 25^th, 2009, 10:00am

Hello,

Thank you for the reply. I confused the terms indeed but your post clarified the issue enough.

BR.