FAQs from Rohde & Schwarz

Verification of FM Chirps using R&S Pulse Sequencer software and Transient Analysis Spectrum Analyzer Option K60

Description

This summary intends to give a fast overview for generation and verification of FM chirp signals using R&S Instruments and software Tools.

User is encouraged to visit the references at the end of the article for more detailed information.

Resolution

Using R&S Pulse Sequencer V2.0 a sequence of 4 different chirps has been defined:

FAQ Verification of FM Chirps - screen 1

For a fast identification of the different chirps in the time domain, the following frequency deviations were selected:

2MHz, 5MHz, 10MHz and 15MHz

The chirps fall in the “Pulse” element type inside Pulse Sequencer and they were all defined with a period or PRI of 2 ms and a pulse width of 1 ms. The modulation fashion was defined as “up” in all cases, which means the frequency modulation is always increasing.
Below the details for the 2MHz chirp inside Pulse Sequencer Menu, all chirps were defined in the same manner with the exception of the frequency deviation parameter.

FAQ Verification of FM Chirps - screen 2
FAQ Verification of FM Chirps - screen 3

Afterwards the train of chirps was uploaded into one SMW200A (FW 4.80.041.57) and the signal was verified using one FSV3030 (FW 1.40) with option K60 for transient analysis. Below how the results are presented after capturing one sequence. The frequency deviation of the chirps are automatically detected and presented under chirp results.

FAQ Verification of FM Chirps - screen 4

User can double click in the upper right diagram called “FM Time Domain” which allows to clearly see the four previously defined frequency variations for the whole sequence of four chirps in the time domain,

FAQ Verification of FM Chirps - screen 5

The next few images highlight the main settings inside K60 to achieve proper demodulation results. The measurement time was also increased to 20 ms to display more chirps simultaneously.

FAQ Verification of FM Chirps - screen 6
FAQ Verification of FM Chirps - screen 7
FAQ Verification of FM Chirps - screen 8

References:

SMW200A Product Page
https://www.rohde-schwarz.com/de/produkt/smw200a-produkt-startseite_63493-38656.html

FSV3030 Product Page
https://www.rohde-schwarz.com/de/produkt/fsv3000-produkt-startseite_63493-601503.html

Pulse Sequencer Product Page
https://www.rohde-schwarz.com/de/produkt/pulse-sequencer-produkt-startseite_63493-374528.html

Automotive Radar Sensors - Transmit Signal Analysis and Inference Tests Application Note (Gloris link)
https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/dl_application/application_notes/1ma267/1MA267_1e_automotive_Radar.pdf