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Post subject: Circuit Envelope Simulator Question..
postPosted: Fri May 21, 2004 11:55 am
ADS to simulate a PA (modeled by a .p2d file) feedforward linearizer.
Anyone knows if in circuit envelope simulations the group delay of the
amplifier is actually evaluated?or should i include it as an external
tnx in advance :wink:
Unread postPosted: Sat May 22, 2004 2:35 am
I think you may add the group delay option in the HB simulation
engine. When you simulate a linearizer you use HB or LSSP engines to
view the non-linear S-parameter results. There should be an option to
view the group delay of the circuit as you do it with linear simulation.
I should also check this option myself. If not, then try to use the
S-parameter engine only and check the group delay option.
Feedforward is not trendy nowadays, there are Pre-distortion techniques
which are more popular. If you need information I will be keen to help
Unread postPosted: Wed May 26, 2004 5:03
tnx for the reply.. :)
i need to use envelope simulation
to see the behaviour of the linearizer when fed with complex signals,
in the controller there is no any group delay option. as long as i remember
it is peculiar of s-parameter controller, and is used to store in a
variable called "delay" the group delay calculated from s-parameter
anyway i am almost sure it is not evaluated in simulation
and so am using an external delay element. if someone has a final ansewer
on the subject i am listening ;-)
Unread postPosted: Thu May 27, 2004
Are you using the Ptolmy tool for envelope simulation
or another tool?
You said that you use an external element for
delay, Are you using it as a constant reference delay at the input and
by that derive the the delay that your system contributes?
must be a delay option that as you said is calculated from the delay
of the S-parameters: delta phase/frequency, and from that the group
delay is derived. I used it myself not long ago to find a group delay
of a filter.
Unread postPosted: Fri May 28, 2004 10:31 am
i am using envelope inside the RF/Analog simulator,
i introduced a delay element after the amplifier
to simulate the effect of the group delay, because i didn't see the
effect of the group delay on the previous simulations results.
i couldn't find any option related to group delay in envelope controller,
i looked in the hidden parameters (the ones in the display tab) but