Hello and welcome. In this video, we�ll
be discussing Momentum, a versatile planar electromagnetic simulator that accurately
accounts for electromagnetic effects in your designs. We�ll start by setting up a Momentum
simulation. Next, we�ll discuss some simulation options, such as frequency, RF versus microwave
mode, meshing, farfield analysis, and then finally, a patch antenna analysis using Momentum. Momentum is one of the more versatile tools
within Genesys. Not only can we evaluate the circuit such as this microwave filter, but
also antenna structures, as well as physical structures which do not have closed form solutions. Here you see the layout for our microwave
filter and then the response. The response represents the linear simulation of our circuit.
To perform a Momentum simulation, we go to the workspace tree, analysis, and then add
Momentum analysis, and here we see the dialog for Momentum where we set up our parameters.
We can change the name, the design layout. If we have more than one layout, we can point
to different layouts. We can change the dataset name if we want or accept the default. Description
is just for adding notes to ourselves for future evaluation. The frequency range, in this case, we�re
going to mimic the linear frequency range, and that was 1.125 GHz to 2.375 GHz. And you
see here it�s mimicked to sort of the range that we did our linear simulation to. Okay, the next thing we want to do is set
the type of sweep. We can select the number of points as you see here. We can do a log
points per decade. We can do a linear step size, like in this case it�s 100 MHz, or
we can do the adaptive frequency sweep, which is the most popular use of it. The number
there, the 25, represents the maximum number of simulations Momentum will do before it
attempts to plot a fast frequency or adapted frequency sweep. Automatic recalculation. If you have tuned
parts, you�re changing physical dimensions. You would like it to do an automatic recalculate.
One of the more useful features is this select and connect layout before simulating. That
connects everything else � everything on the layout. If you�re doing tuning of physical
dimensions, it does that automatically for you. We can select units to be GHz, terahertz,
MHz, or whatever we wish. We can change the default impedance from 50 ohms to 100 ohms,
or whatever works. In addition, you see this box for �use EM
frequencies.� It�s checked right now. If we uncheck it, then what we can do is set
a start and stop frequency and change the number of points. This is helpful if you�re
trying to generate data that exactly matches let�s say a linear simulation where you
may have 101 points and you want the number of frequency points, data points, to match
up. And the reason you would do that is if you were trying to model some circuit to an
EM simulation, so that�s helpful for that. Under the options, primary options, are RF
or microwave mode, the RF mode is primarily a static solver. And microwave mode, we need
to use that when we do farfield or antenna analysis, as well as when the circuit becomes
an appreciable portion of a wavelength. The 3D metal expansion, if we have thick metal,
up basically means that the metal is above the substrate. Down, it protrudes below or
into the substrate. The via models where generally we just take
the 2D model, but you have a selection there. The solve matrix, it�s usually set to auto-select.
But if you�re running out of memory, you might choose the iterative solver for that. The check box for a used box basically puts
a box around our circuit and allows us to have a metal box around it, and we can also
have an open box at both ends. But basically that�s what that means is to use a box. The mesh, we usually allow that to use the
analysis frequencies or we can manually set a frequency for meshing. Mesh density defaults
to 30 cells per wavelength, as well as the arc resolution that tells the resolution or
the arc of segments that are used for meshing up round circles and so-forth. And the rest of these we primarily leave automatic.
If you wish to know more about this or peruse that, I would welcome you to check out the
help so you can influence your learning, extend your learning. Farfield options, you�ll notice we get a
dialog here that says we haven�t done a microwave analysis. Of course we haven�t.
And that�s necessary in order to do a farfield calculation. But we�ll show you how we do
this later for an antenna example. Now that we set up our Momentum analysis,
the next stage is to run it, so from the green arrow we�ll select �run�, and in a few
seconds we�re done. Okay, here you see the completed simulation. You�ll notice that
we now have gridding on our layout, and you�ll also notice that the gridding is tighter towards
the edges where the current intensity is higher, and this is automatically generated by Momentum. What we�d like to do now is compare the
circuit analysis to the Momentum analysis, so I�ll double click to open and add more
measurements, and I�ll change my data source to Momentum data and then select S11. Press
�okay� and that adds the S11 to our plot. Again, I�ll do the same thing again selecting
Momentum dataset as S21, and now we have both the linear simulation and Momentum for comparison. Because Momentum accurately models nonadjacent
coupling between resonators, as well as other parasitic affects, we get much more accurate
results than we do with the linear simulation. What I�d like to show you now is some of
the versatility within Momentum and how you can use it for antenna design. Here we have
a plot Momentum simulation of this patch antenna, and we can see the frequency response, and
when I right click on this, I can bring up the properties and you can see how we set
this up for your antenna simulation or farfield. We�re sweeping from 1.8 to 2 GHz. Under
our simulation options, we�ve selected microwave, so we can in fact view the farfield. And we�ve
selected to calculate the farfield. Also, to get the 3D information, we�re collecting
all the values for phi and theta. And we select an EM frequency of 1.883 GHz, which is close
to our center frequency. You�ll notice we specified a magnitude and
phase for our voltage. This is not so important unless you�re using two or three patches
at one time, and you can change the phase and angle of each of those. If I then right
click, and then out at the bottom you see a selection for a 3D visualization, and here
is the 3D visualizer or 3D viewing, and the first screen that you see here is the patch
itself. We can view the various layers, both above and below our patch antenna that is
a substrate in the air above. And here we can set up which frequency that we want to
view the currents and the antenna radiation pattern. Under the plot properties, we can set the
transparency. We can add arrows to our plot. We can change the size of those. We can change
it to log scale if we wish. We can even animate it so we can watch the current�s real time
on our patch antenna. We also have preset viewing positions, both isometric, top, down,
side. We can dynamically change this if we wish both for scale and zooming in. And then
we also have a query so we can look at the currents of different parts of our patch.
Oh, I might also add, we can also view the mesh if we wish to simultaneously. I�ve selected the farfield, and we�ll
bring up the farfield plot, and here you see this � the plot, you can have the total
E field that we�re showing here, or theta or phi or crossfield. We can do a log scale.
We can do normalization or not normalization. Of course you see the change in the plot as
to whether it�s plotted versus log or linear. We can change the transparency if we wish.
And as you see here, I can rotate the plot manually just like we did with the patch antenna.
And then there are preset patterns or preset views that we can also use, and then we can
view the antenna parameters. Things like radiated power efficiency, effective angle, directivity,
gain, all of which are important in antenna analysis. So, what I hope I�ve showed you is how easy
it is to use Momentum and how an effective tool it can be. Thank you.