Contents
What is a spectrum analyzer used for?
A spectrum / signal analyzer measures the magnitude of an input signal versus frequency within the full frequency range of the instrument. The primary use is to measure the power of the spectrum of known and unknown signals.
What causes electromagnetic interference?
Electromagnetic interference (EMI) is an electromagnetic emission that causes a disturbance in another piece of electrical equipment. It can be caused by direct physical contact with a conductor, called conducted EMI, or by induction (without physical contact), called radiated EMI.
How can you protect from electromagnetic interference?
The simplest way to reduce magnetically induced interference is to use twisted pair wires. This applies both for shielded and unshielded cables and for interference caused by shield currents or from other sources. Twisting the wires forces them close together, reducing the loop area and therefore the induced voltage.
How to avoid interference with a spectrum analyzer?
If possible, turn off the wireless network before taking readings with a spectrum analyzer so that the analyzer only displays the amplitudes of potentially interfering signals. That way the RF signals that the wireless network emits will stay out of the way when you’re analyzing the interference.
Why does my spectrum analyzer show constant amplitude?
An interfering signal that occurs often (which means it’s harmful) causes the analyzer to display relatively constant amplitudes that you can easily see in the display. You should record and analyze spectrum images for each source of RF interference to determine its impact on the wireless network.
Which is the best tool for radio frequency interference?
For most narrow band interference sources, such as co-channel, adjacent channel, and intermodulation interference, the recommended tool is the spectrum analyzer, as this allows you to focus on particular frequency channels or bands and see the big picture of what’s occurring.
How does a normal mode spectrum analyzer work?
Spectrum analyzers have multiple methods for displaying signal amplitudes. Normal mode is generally when the analyzer displays amplitudes that change quickly in step with the actual signal as the signal changes. This is a measurement of what’s actually happening in the spectrum.