Hello there my name is Ben Maxson and I'm an Applications Engineer with Copper Mountain Technologies based out
of Indianapolis, Indiana and welcome to this video overview of the Copper Mountain Technologies
USB VNAs. What you see in front of you right now is our website, the main landing page
of our website, and what I thought I'd do to get started is to show you how to access the
software of the instruments and get that installed. And while we go through that I'll also mention
some aspects of the USB connection. Which is what makes our instruments but different
from the traditional instruments that are out there. You're probably very familiar
with those. So to get started with the software let's go to the support page and find "Downloads".
Here you can find downloadable executable installers for all of the different instrument
families. There are four families. The R-series is our 1-port VNAs. The S2 series are the
2-port VNAs which can reverse, meaning you can measure all 4 S-parameters. S4 is predictably is the
4-port VNAs. TR is for our TR series of 2-port VNA is that only measure two parameters;
they only generate from Port 1. So those are are called 2-port 1-path VNAs. So today
let's let's go ahead with the S2 software installer. It's downloading. As it does so I'll
just mentione that the USB interface is really what makes our instruments different from
the traditional instruments that are out there. The USB connection is a plug-and-play
interface which is pretty well-suited for Vector Network Analyzer Applications actually
because the raw data rate of VNAs is relatively small especially compared to the bandwidth
of USB. Even USB 2.0 is hundreds of times faster than would be required for a VNA so unlike
something like a real-time spectrum analyzer the USB interface is not bottleneck in any
way for the VNA. So it looks like our download is completing, we'll just go ahead and run that. You may encounter some security
messages as you as you go through the installer depending your browser and operating system
configuration. I'ts safe to ignore those some. So, here we have our first decision to make with the installation
the analyzer model can be selected from among all of the 2-port VNAs that we offer.
You can you can choose to autodetect the VNA, and that's probably the best selection so that
you doon't have to dig through the menus to find the correct analyzer once it's installed. You can
also choose initial analyzer model. I'll use the default of C1209. it's also possible
to lock the installer to a specific serial number. That can be useful if you multiple
instruments connected to the same PC and want to use a different software for specific instruments.
Now we see the demo mode option. Demo mode is basically a simulator of the VNA so it's
possible to run the Demo mode software without the physical instrument. I'm going to choose to
do that today since I don't have access to the VNA here, but if you have the actual VNA you would probably
want to uncheck this box and just install in Full mode. You always can change this setting later.
Here we choose our installation path; I'l choose the default which already exists on my computer.
That's fine. And the full installation includes some operating manuals, programming manuals and
and guides, and some other useful utilities and tools. We'll go ahead with everything. Desktop icon will be fine.
And now we want to make sure that we leave this box checked on the last page to register
the COM server. The COM server is necessary if you want to automate the measurements from
a program like LabVIEW, Matlab or any other programming environment. We'll come back to
that but the key thing here is to make sure that we do register the COM server when we install.
And here see the success dialogue that that did indeed happen. So now's we're ready to launch the VNA software. I have a shortcut on my
my taskbar to do so. And here we are, we're up and running with the simulator mode. You see here in the title bar here
we see simulator mode which is also known as Demo mode. So this is a simulated result
the simulator's actually pretty sophisticated in the sense that if we change instrument settings. The simulator is actually pretty sophisticated,
in the sense that if we adjust the setings it will adjust the sweep speed and things to approximate the the reality would see we
if we did have a physical VNA running. OK so now, let's go ahead and explore the user interface
here. If you're familiar with VNAs you're probably are thinking this looks pretty familiar.
You have menu buttons along the right side of the window here, as well as a drop-down menu
along the top. These have more or less equivalent functionality so you can use whichever you
prefer. In general the the right side menus are my preference. In some cases, some of instruments
have just a subset of features in the drop-down. So you can always get the full set of features
using the right side menus. And that's what I'll do today. So to start with, we might want to configure
our stimulus--the generator of the instrument. You can see that right now it's set up for the start
and stop frequency of the full frequency range of the C1209 VNA. If we wanted to adjust those
we could do so by just clicking on these and entering in a preferred start value. We'dl use 5-capital-M for megahertz
and maybe we'd want to stop at 8-capital-G for the Gigahertz. Alternatively you can click on these axis
labels directly, and enter new values down here. And also, if you mouse over the start of the
axis, you can click and drag. See that? So I can increase the start frequency to a prefered value
using the graphical representation here. Why don't I zoom in just on the passband of this filter.
We're simulating a bandpass filter basically. And now I'll show you how to change the display format. So one
way is to click on the display format indication above the plot and just choose display format you prefer.
So, choose a Smith chart for example. Alternatively, and we'll go back to the main menu
by clicking at the top of this menu. There's always this little back arrow here to remind you. We could
also change the format using the format menu. So here are the different options we have for
the display format. I'll go back to the Log Magnitude. OK so returning to stimulus just briefly,
we can also specify the number of points, sweep type--all the instruments have a power sweep option
except for the one port VNA's. That's included as a base feature. As well as the segment mode.
You can set the output power of the instrument. So currently it's at its default of 0 dBm. C1209 can go
as high as +15 dBm. And of course if you enter value in any of the control fields which is in excess
of instrument's capability it will just limit to the to the maximum or minimum of the instrument
accordingly. We can also set a measurement delay and some advanced features here related
to the trigger, but the for purposes of a quick demonstration, we'll leave those at their default values.
So a next point to show you will be multiple measurements. So right now we're
looking at just S11 in a Log magnitude format. If we wish, we can add multiple traces, up to 16
traces per channel. And we can spread those up to multiple graphs so we can see them individually.
So here we have S11, S21, S12 and S22, all four plotted at the same time. Why don't we go back to
the full frequency range of the analyzer, so that we can see the overall response. So here you can see it is
a bandpass filter, with reflection parameters here on these diagonal graphs. Let's try to find the
stopband of this filter, because it's off the bottom of the display right now. So we'll
do that on scale menu. We can choose Auto Scale All to automatically adjust the parameters
of all plots in the channel according to their current measurement values. There we are, now we can see the stop
band noise down here a little bit. And if we wanted to see a little further down into that noise, of course we can reduce
our IF bandwidth. It'll slow measurements down but allow us to see a lower noise floor. So we can
do that either on stimulus menu--here you see IF bandwidth-- or on the Average menu, or using this
control at the bottom below the plot directly using the mouse. If we right-click there we see the full
range of IF bandwidths available. Let's choose something more like 100 Hz, so now you can see the noise floor has
dropped off the bottom again. We'll go back to scale and Autoscale All. And now we can see the noise
floor its significantly reduced, about 100-110 dB. So we're looking down there pretty
good into the noise. And of course we could reduce it even further but it would slow the sweep down
even more. So we'll not do so for. I'll also also show you an addition to the IF bandwidth, on the
averaging menu you can set the number of averages and enable averaging. You can also enable smoothing
if you wish. And now you can see the noise is starting to drop even further. We'll see the number of averages reflected
down here instrument as the instrument continues to sweep. So I showed you how to make multiple traces. I'll also mentione
possible to also have multiple channels--up to 16 channels--with up to 16 traces per channel.
An additional channel allows you to have a separate control over the frequency range
and output power. So the stimulus for all the traces in a given channel is the
same. That's sort of what makes a channel different from traces. If you need say a frequency sweep
and a power sweep, you could add a second channel and configure it for power. Or if you wanted to see
a wideband response with one plot and the passband response with the second, you could do so with a second channel
as well. As an example we can put a Smith chart here with just our passband. And explore our
narrowband response on right, and wideband response on the left. For example. Normally people will be using
just one channel and multiple traces in the channel. OK so that's the basics of the stimulus
set up and display format controls. There are many more options here, but in the interest
of time, I'll just highlight the main points. So calibration will be next next point
we can talk about. Calibration of the VNA of course accomplishes two goals. One is to compensate
for the VNAs exact parameters at the time of measurement. The second is to compensate
for losses and delays of any fixtures that are connected between the instrument's ports
and the device under test. So that includes any cables, adapters, in some cases amplifiers and
other components. You want or you want to remove the response of those fixture elements
from the measurement. You want to measure only the device under test. That's the second
main goal of the calibration process. So there many many types of calibration, variants of
calibration algorithms. The common thing of all those is that there are three main steps.
One, is you have to know the correct response--the true response--of one or more calibration standards.
And obviously you need to tell the instrument what those are. Secondly you need to measure
those standards with the instrument. And then third, and the instrument takes care of this
for you, you need to compute the difference between the known response and the measured response,
and calculate what the correction parameters should be in order to achieve the the best
possible, most accurate response, given those two pieces of information. The first step,
defining the known response of one or more standards, we'll accomplish on the cal kit
menu. Click Cal Kit and here we see below the plot a list of some very popular calibration
kits from a wide range of vendors, including some Copper Mountain kits but also waveguide
kits from Flann, some popular kits from Keysight (Agilent kits), Rosenberger, Maury, Spinner. And of course
this is a list of the most popular kits. But if you have a kit
that's not in this, it's pretty striaghtforward to either modify one of the existing kits or to create
your own using the empty spaces at the bottom of the table. We've got plenty of room
there to define a lot more kits if we need to. Just quickly we'll dig in to one of the kids here, the
default selected kit. And you can see here are the parameters of the kit. Rregardless of what
kit you're using the vendor has provided you with definitions of the standards similar
these. These can all be edited by simply clicking in the table. You can import and export
these to files as well. And here's where you'd enter the polynomial coefficients for
your Open and Short. And provided delays as well. Basically that's how you define a kit. So now,
how do we use that kit to do measurements? Well, you come back to the calibration menu
menu. Click the calibrate button. And here you can see some options for different calibration approaches.
Those range from simple normalizations of the, Open, Short, and Thru to a full 1-port
Cal, full 2-port cal, 2-port 1-path cal--if we happen to just be measuring S11 and S21 (or S22 and S12).
And also TRL calibration. And adaptor removal, unknown thru removal are some advanced
calibration options we have. Most commonly people would be doing a full 2-port calibration
on a 2-port analyzer. And again this is the demo software, so calibration is not going to be a terribly
useful thing. But if we were using the physical instrument, we would just simply connect the standard to our
fixture, enter this menu, click on the corresponding standard type, the instrument would perform
the measurement--we can do that step here--and you can see it performs the sweep, beeps to let us know it's done. We
see a checkmark here, and if we come back to the higher-level menu we see there's a checkmark showing
us we've done the Port 1 Open. We would just need to proceed through Port 1 Short, Port 1
Load, Port 2 Open, Short, Load. Thru, and here we would have option for Thru or Unknown
Thru. All of 2-port 2-path instruments support unknown thru calibration. Isolation
is an optional step, it's normally not recommended unless your fixture is especially prone to to
poor isolation. Reason being that the dynamic range the analyzer is well in excess of its
isolation and so the isolation calibration will actually reduce the dynamic range if it's used unnecessarily.
If we were to go through all the necessary steps here we would have the Apply button clickable. Click that,
and corrections would be computed and applied to the measurement. I'll cancel since
again we're using the demo software. But we would see corrections enabled here and of course
we go always turn those back off or on to see the effects of our calibration later. OK, so that's calibration
in a nutshell. I'll just you quickly the markers as well. So if we want to add a marker to a trace, we just select
the Trace. You can see which trace is active by this indicator in the title bar. You can click on Add Marker.
You can see that by default, the marker's coupled across all the traces in the channel. If we want a
different functionality we can go to Marker Properties and disable Marker Coupling. Now you can see each marker
can be repositioned independently of the other traces. You can also select the active only, which
will, when a new marker's added and active only is selected, it'll add it only to the active trace.
Also, if you wish to see the marker data summarized in a table it's possible to come
in here and enable the Marker Table. And that just shows you as you all marker data duplicated in this table
below the graph. It can sometimes be a little more legible there. You can also reposition
any of the markers by clicking and dragging to more convenient location on any individual
plot if you wish. So that's Markers. Now let's explore the Analysis menu quickly. You can see a number of different
analysis options, including time domain and gating. Notably those are free and included standard
features of all of our instruments. A nice convenience to have. Fixture simulation allows
you to embed or de-embed S-parameters. If you happen to know the S-parameters of
a component in your fixture you want to remove, you can do that here. Conversion allows you to convert
convert to reflection or transmission parameters instead of the linear plots here. General conversion
is simply more complete mathematical model of the same. Limit testing allows you to
set Pass/Fail limits for each individual trace. It's quite sophisticated you can have
multiple different frequency ranges, some minimums, some maximums, with a Pass/Fail indication directly
on the plot if you wish. It's very helpful for production environments, where the operator
may or may not know exactly what how to interpret the measurement result. There's also ripple
limit, and some other options there. So explore the analysis menu at your leisure. Finally
I'll mention the Save and Recall features and I'll mention a little bit about automation of the
software. So there's a number of different options for saving and recalling the data and
the plots in the analyzer application. First, there's a saving the state. Before we go there, I'll
mention that it's important to note the Save Type. This will dictate what type of file we're going to save when we
click Save State. We can either save just the instrument state meaning its settings, state
and its calibration data, that' the default, the state of instrument and its trace--
the actual trace that's displayed on the plot--or we can choose All if you wish
to save State, Trace, and Calibration. I'll just go with the default of State and Cal. So here we
can come in and save the state to any of these predefined state files, 1 through 10.
Or if we prefer to give it a more intuitive name we can save it with a file name "Mystate"for example.
So now, if we we change our settings and want to get back to the known state file,
we can just go to Recall State, File and choose the same. And the settings will be restored including the
alibration data. That's a nice way to get the instrument back to a known state and especially useful if
you're performing a few different measurement types over and over. You can
get the instrument configured exactly the way you need it for a particular test, save the state file,
and then simply recall the state file to get everything back the way that you need it for that test
if you need to get back there again. That's saving state. You can also save Channel, which is
helpful if you wanted to say duplicate all of the settings of this channel into a second
channel. You can save it to Channel A and recall it into a second channel is in this menu. And
finally, I'll mention also you can save the trace data, if you wish, to a CSV file. This will save
the active trace and it will save the frequency as well as the magnitude and phase if you've selected
a complex display format into the CSV file. Which you can then, of course, open in Excel or any
other suitable program. And finally you can save the data to a Touchstone file, an S2P file,
very commonly used for S-parameter data sharing between applications. And there's a number of options
there. Interestingly can also recall data from a Touchtone file. You can recall it either to
replace the measurement data, or into the memory traces. That's especially useful
if you want to compare the live measurements to a saved measurement result that's in a Touchtone
file. And then finally, on the system menu, System > Print allows you to save the plot to
file, as opposed to the data itself. So Print Windows will just take a screen grab of the
plot area and save that to file on our hard drive. Which of course we could then copy and paste into an email,
if we lcoate on this we can rename this to something more intuitive, and save it off into
a shared folder. It will open with your default image handler once it saves. Print > MS Word will actually,
with a single click, create a Word document and paste the screenshot into it. Which can
be helpful for semi-automated production testing. Maybe there'd be a field there for an
operator to fill out some additional fields manually. Print > Embedded is helpful for
literally printing the file. It uses Windows' embedded print dialog to to literally
send the the plot to a printer. Including print to PDF which can be nice. And then the final
thing to note on the system menu: here's where we find the preset button, where we can get the instrument
back to all of its default settings if we wish to do so. Sometimes, you can get off in the
weeds, and it's nice to get back to a known good starting point. I'll just put my four traces back up quickly here.
I'll also mention System > Plug-ins. Here you'll find a number of different software extensions to the
mainland software. And we can create plug-ins like these in response to your particular
test requirements If there's something you need the instrument to do that's just not
quite there in software, let us know, by all means, and we'll see about making a plug in
to support that functionality for you. The plug-ins make use of the automation interface of the
instrument, which is what I want to show you next. The instrument's fully programmable. You can
find its programming manual in the \Doc subfolder of your install path (of course that's on our website
as well). This document goes through in quite a bit of detail all the different commands
that are available. You can see it's quite a long document, 400 pages long. Going through
basically every command of the instrument. There's more less a command for every button
on the menu. So basically everything you can do through the user interface you can also
do using an external program for automation. You just need to find the appropriate command
and and send it from your your programming environment. The automation interface makes
use of COM server technology which is a Microsoft Windows standard for sharing data
between Windows applications. It's actually very straightforward. Automation is possible
from a wide range of environments including Visual Basic in an Excel file for example,
C++, Matlab, Python, LabVIEW, C#, VB.NET, VEE, LabVIEW/CVI, basically any programming
environment that supports a COM--also known as ActiveX--interface, can support automation. Just
to show you an example of a command definition, you can see here whether it's a property or
method, if it's readable or writable or both, the arguments of the command, and an example of
the syntax in Visual Basic syntax. The syntax is similar for different programming languages
with small variations, but this gives you an idea of how to get started. OK, well, that's been
a quick overview of the Copper Mountain Technologies USB VNA. I hope you find it interesting.
If you have any questions about any aspect of software, or the products, of course feel
free to contact us anytime. You can reach us at support@coppermountaintech.com. You'll
find links to that peppered all around the website; any of those will work. For
quoting, demo units and other questions sales@coppermountaintech.com is your
best bet. We look forward to hearing from you. Thanks for watching.
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