Why, hello there.
In this video, we'll be discussing what a spectrum analyzer is
and the different measurements you can make on it.
My name is...
What the!
Who keeps turning off the lights?
Get that!
What's up, everyone?
The name is Nick Ben, and I'm an engineer here at Keysight
and welcome to this episode of "What the RF?"
In this episode, we'll be discussing what a spectrum or signal analyzer is.
"What is a spectrum analyzer?" you may ask.
This, right here, is a spectrum analyzer.
A spectrum analyzer basically analyzes spectra.
Alright, fine, fine, fine,
there's more to a spectrum analyzer than I actually let on.
If you've ever used an oscilloscope like the one that you see right here,
then you know that it displays received signals with respect to amplitude versus time.
Now on the other hand, a spectrum analyzer displays received signals
with respect to amplitude versus frequency.
Now, in terms of a simple analogy for this very complicated electromagnetic topic,
I guess you could say it's pretty much like comparing the same data
between a pie chart and a bar graph.
Here, we see that Daniel has eaten eight pies,
Nick has eaten two pies, and Ally has eaten one pie.
Also here, we see that Daniel has eaten majority of the pies.
This can only mean that Daniel really likes pies.
For those of you that don't know,
the terms spectrum analyzer and signal analyzer are used almost interchangeably,
but there are some slight differences.
Spectrum analyzers display a signal's amplitude as it varies by frequency,
but by definition, a spectrum analyzer does not measure the phase of your signal.
Now, without this phase information of your signal,
we wouldn't be able to measure, for example, digital communications
like LTE on your cell phone.
On the contrary, a signal analyzer like this one measures the amplitude and phase of a signal
at a single frequency.
If you transmit an RF signal from your device,
a signal analyzer can downconvert the signal into a digital signal
and the signal analyzer can display the signal in terms of constellations,
spectrum, power versus time, et cetera.
Basically, a signal analyzer can measure both amplitude and frequency
and phase of your signal of interest which you can't do on a spectrum analyzer.
Now, let's learn what kind of measurements we can make on our all-knowing signal analyzer.
The main use of a signal analyzer is to measure the power
of a signal's various frequency components like radio frequency and audio signals.
A signal analyzer allows you to analyze your device's signal and circuit performance
in a way that isn't possible using other means.
Say, looking at it in the time domain.
Spectrum and signal analyzers can make a large variety of measurements
ranging from harmonic distortion tests for transmitters,
WLAN analysis, and spectral masks for showing limits of unwanted emissions,
to two tone tests on an RF power amplifier.
Because of how powerful a tool a signal analyzer is,
it is practically owned across all engineering labs for design development
and testing of engineers' devices.
If you need to see the frequency makeup of your signals,
a signal analyzer is a great tool to have.
Also if you'd like to dig deeper into spectrum analysis,
check out the application note in the description below.
That's it for this episode.
Thank you so much.
What the RF?
Who keeps turning off these lights?
Hello?
What the RF?