ADS Software - Transient Simulation Software

[Gae81]

Hi guys,

i'm using simulation software Agilent - ADS to perform a mixer design.

Circuits contains microstrip lines and is very close to be the final realization.

I had two simulations, one is Harmonic Balance and Transient the other one.

I noted differences about results, and i can't understand which of these

give me correct datas.

Can anyone help me please ?

Thanks in advance, Gae

 

[pancho_hideboo]

I had two simulations, one is Harmonic Balance and Transient the other one.
I noted differences about results,
and i can't understand which of these give me correct datas.

Informations you provided are too few, so no one can judge which result is correct.

Show me simulation results and simulation settings.

If your simulation settings are proper for both HB and Tran, you can get almost matched results between HB and Tran.

But I think results of HB could be correct than Tran since your circuit include microstrip lines.

 

[Gae81]

If you agree with me, first of all we should check if results are not consistent.

So i send to you this picture where i show different results.

 

[Gae81]

I forgot one thing : why did you say that

HB is more accurate since i use microstrip ?

Transient fails with microstrips ? Thank you.

 

[pancho_hideboo]

If you agree with me, first of all we should check if results are not consistent.
So i send to you this picture where i show different results.

It seems that you are not so familiar with Agilent ADS.

Show me your netlist regarding analysis statement, microstrip, signal source and accuracy settings.

I forgot one thing : why did you say that
HB is more accurate since i use microstrip ?
Transient fails with microstrips ?

Do you understand how microstrip is treated in Transient Analysis ?
It is treated by convolution generally in Transient Analysis of Agilent ADS.

If you understand difference of treatment of microstrip in HB and Tran correctly, answer is self-evident.

 

[BigBoss]

It's normal..;
In a transient simulation, the waveform covers all harmonics and you're not able to see these harmonics seperately.You see only all harmonics in a single shot as a waveform.
But in HB, harmonics are seperated and each one has its own amplitude.

The power should be in HB,

Power=10*log(0.5*VLoad*conjg(I_Load))+30 (dBm)

 

[pancho_hideboo]

The power should be in HB,
Power=10*log(0.5*VLoad*conjg(I_Load))+30 (dBm)

Oh, I missed such too simple mistake.
His calculation of Power in HB is wrong as you pointed out.

P has to be dBm(v1, 50.0) not 10*log(abs(v1)*abs(I_probe.i)*0.5*1000).

This is his fatal misunderstanding.