How to measure Ultra Short Radar Bursts
Since the SPECTRAN V6 offers an ultra low POI, within the ns range, you can capture and even decode a radar signal with the cheap SPECTRAN V6 RSA250X unit.
The first screenshot shows our radar under test operating at 3350MHz with a regular 2048 point FFT and a POI of 33µs:
Although this shows a lot of burst packages it does not give you the real picture of the radar signal. This will change if we use a smaller FFT resulting in a lower POI. The next screenshot shows a 16 point FFT with a whopping POI of 195ns. The frequency domain gets sort of blurry, since we only have a 16 point FFT, but the time domain now gets realy interesting. We can see short and long bursts within the µs range:
The 2D and 3D waterfall views still have a time compression of factor 10. If we reduce that to 1 (real-time) we get a much better picture about what is going on. We can now see that the longer bursts have a length around 6µs and seem to have a own package structure:
If we now zoom into one of those bursts we get the full picture. They have some sort of coding with a pulse length of around 400ns. The 3D waterfall shows a great picture of the pulse. It shows this to be a phase modulated pulse using Barker code of length 13. Nice!
An finally a Multi Spectral view of the RF emitted by the radar. A great finger print!
Please check out our latest video showing above radar pulse decoding: Radar Pulse Decoding
