You have your workspace set up with your oscilloscope, waveform generator, and vector network analyzer. Now all you're missing is some desk space to actually do your work. What if I told you that you could get the same performance from machines half the size of your current setup? Small form factor equipment is a great option for labs where space, cost, or portability are concerns.
Figure 1. The P937xA Keysight Streamline Series VNAs are easily controlled via PC.
The P937xA is part of Keysight’s Streamline Series, a new family of faceless USB instruments, including vector network analyzers (VNAs), oscilloscopes, and an arbitrary waveform generator (AWG). By moving the user interface (UI) to a computer, we were able to pack our proven hardware into small devices with incredible performance for the price.
When you buy instruments, you’re not just buying the hardware. You’re buying into the manufacturer’s ecosystem.
In addition to the dependable hardware, the Keysight Streamline Series also comes with our intuitive UI to give you the same experience as full-size instruments. This means that the P937xA has the same SCPI commands, GUI, and measurement science as both our benchtop and modular vector network analyzers. You can also run our common benchtop applications and software upgrades.
There are a lot of USB instruments out there now. When shopping for small form factor equipment, it can be hard to see the difference between each vendor when they have somewhat similar specs on paper.
Let’s dive into some of these specs and the differences between two of the most popular compact USB vector network analyzers on the market: Keysight’s P937xA and Anritsu’s Shockline MS46122B.
In RF measurements, the name of the game is minimizing interference. In today’s wireless world, RF signals and devices must fight all kind of interference. It can feel like the universe is against you when testing RF equipment – and it actually kind of is – thanks to interference from lightning, solar flares, and Earth’s magnetic field.
Fortunately for you, modern VNAs are built so precisely that even smaller USB instruments boast impressive specifications. You can see the banner specs of the MS46122B and the P937xA summarized in Table 1 below.
Performance / Spec
4.5 / 6.5 / 9 / 14 / 20 / 26.5 GHz
8 / 20 / 43.5 GHz
Number of Ports
2 / 4
Dynamic Range2 @ 10 Hz IF BW
0.003 dB [1 kHz IF BW]
0.006 dB [10 Hz IF BW]*
-40 to +7 dBm
-20 to +5 dBm
-40 to +2 dBm
-20 to -3 dBm
Stability dB/deg. C (typical)
10 Hz to 1.2 MHz
10 Hz to 300 kHz
*Performance is characteristic, not typical
1 All Anristu specifications were found in the ShockLine™ Compact Vector Network Analyzers MS46122B datasheet (PN: 11410-00995 Rev. F) on June 20, 2018.
2 Standard (not typical)
Table 1. Keysight P937xA and Anritsu Shockline MS46122B banner specifications.
It’s easy to just throw numbers around, so I’m going to explain why you should care about these numbers.
Dynamic range, power range, and IF bandwidth are the holy trinity of noise reduction. Flexibility with these specs gives you space to separate your signal from the noise.
Dynamic range is the power range of simultaneous input signals that can be accurately measured. This is critical for applications like characterizing filters where the stopband and passband power levels can vary greatly. A wide dynamic range provides more room to set wide IF bandwidth to speed up your measurements.
A good power range is essential for characterizing nonlinear devices with a power sweep. It also allows you to run tests without an external power amplifier, saving bench space and keeping your cost of test down.
IF bandwidth is one of the most important network analyzer parameters. It offers control over the trade-off between noise reduction and measurement speed. As you can see, the P937xA gives you about a half-order of magnitude more frequency to work with.
It sounds great on paper, but how does it look?
We all want our products to get to market as fast as possible. An intuitive user interface is critical in speeding up the development process. Easily move through each phase with quick access to common tools and menu options.
Note: All Anristu screenshots below were taken on a MS46122B by a Keysight employee on February 21, 2018.
Figure 2. User interface of Keysight P937xA vs. Anritsu Shockline MS46122B.
Setting a trigger is one of the most basic needs in making measurements. Having the trigger button right on the main menu of hardkeys makes it so you are always one button press away from the full trigger menu. No need to dig through various menus to set up one of the most critical components of a measurement.
Figure 3. Trigger menu on Keysight P937xA vs. Anritsu Shockline MS46122B.
Adding a trace, undoing or redoing an action, or taking a snapshot has never been easier. The P937xA user interface has shortcut icons along the top of the screen for common quick actions.
Another helpful capability of the P937xA is the setup wizard. Having all the fundamental steps and parameters in one place makes setup a breeze. There is no need to dive into multiple menus when you have everything in one place.
Figure 5. Main parameter setup on Keysight P937xA vs. Anritsu Shockline MS46122B.
The P937xA also supports context menus with a press and hold (or a right click). These menus give you quick access to different features depending on where you click.
Figure 6. Right click quick access menus on Keysight P937xA.
Another feature that will come in handy is the drag and drop for different trace views. This lets you simply drag each trace and place it in a portion of the screen that makes it easier to view the data. This helps make the view more customizable to your specific tests rather than being restricted to a pre-defined menu.
Figure 7. Easy drag and drop traces on Keysight P937Xa vs. display options on Anritsu Shockline MS46122B.
As we’ve seen, the P937xA’s interface is full of intuitive features to make your measurements easier.
In summary, we’ve seen that the P937xA offers excellent measurement capabilities with the same UI you would get from a high-performance benchtop instrument. The P937xA’s stability and very low trace noise mean that once you calibrate it, you can be confident in your measurements. The intuitive user interface ensures you’ll test more efficiently and speed up your development phases. Altogether, the new Keysight Streamline Series USB VNAs pack big performance into a small package so you can fit even more functionality on your bench.
Compact form. Zero compromise.
Click here to learn more about Keysight’s Streamline Series USB vector network analyzers. Or check out the video demo.