Saturday, January 22, 2011

Radar Ranging

I think I got some pretty okay ranging results. You've got to use your imagination to make it out. I resorted again to taking a screen capture of my webcam and the radar data...
video

The embedded videos are downsampled. Here's the original screen cap.
Notice that, as I scooter away, there is an increasing frequency component. As I scooter back there is a component that is decreasing in frequency. See if you can discern the difference in rising and falling slope. I'm going faster on the return than I am during the departure.

The "Spectrum" graph on the left is a low-pass filtered version of the ranging signal. This is subtracted from the current ranging information so that in the spectrogram only moving reflections are shown. Even with this, there is a lot of "clutter" in the radar image. Also, I'd like to improve the dynamic range. The higher frequency components in the ranging data are a result of reflections from farther away. These signals are attenuated due to free-space path loss. Confer, for example, with when I am right in front of the antennas and there is a significant red mass on the spectrogram.

2 comments:

  1. Gustavo can you list where you got the TX RF blocks from your radar unit?

    Thanks

    ReplyDelete
  2. Hello
    Can I know how can I start capturing the data in Python please?

    ReplyDelete