Folker Hoffmann, Matthew Ritchie, Francesco Fioranelli, Alexander Charlish, Hugh Griffiths
Bottom Line Up Front
I rate this 7.9.
Super cool experiment, I’m frankly shocked that it works as well as it did. I wish I had radars to play with, and results from slightly less cooperative UAVs. Clearly lots of opportunities for ’next steps’ with this exact hardware setup. I want one.
Figure Anarchy
I know LaTeX and maybe even IEEE insist on letting figures roam the countryside however they please, but good lord, this paper is just a description of figures and none of them are anywhere near the text describing them. 4 of them (called 2 figures, because 1 label applies to multiple figures for maximum confusion) are half way through a page with nothing else other than citations on it. Also raster figures that are just lines and text so I can’t even zoom. Minus 1 point just for this madness.
Summary
Intro
Unmanned Aerial Vehicles. Very scary. We can’t get experimental data from multistatic radar systems. First experimental validation of multistatic tracking of a UAV using micro doppler for clutter surpression.
NetRAD system is used for experimental trials.
NetRAD
3 identical separate nodes
- 2.4GHz.
- Linear up-chirp modulation with 45MHz bandwidth,
- 0.6 microseconds pulse duration,
- 23dBm transmitted power,
- 5kHz Pulse Repetition Frequency.
- (Whole UAV micro-Doppler signature is included in unambiguous region)
- Horizontally polarized antennas with 10 degrees beam-width in elevation and azimuth, and;
- 24dBi gain.
Drone
Drone is a DJI Phantom Vision 2+. Ground truth comes from GPS.
Constant False Alarm Rate Detector
Trees cause noise in the 100m bins. Ignore it.
Micro-Doppler Discrimination
UAV can rapidly change velocity and also hover, making it difficult to separate from cluttrer based on Doppler shift alone. Micro-Doppler means it isn’t lost with lower radial velocity.
UAV Tracking
Extended Kalman Filter. 4 degrees of freedom drone, just a 2d Cartesian vector. Wow, UAV process noise is taken as 100m^2/s^3. I’m surprised this works. Nothing else remarkable, but certainly nothing that feels as oddly specific as I was expecting, quite general.
Results
They fly right along the beam, but have very impressive tracking.
Discussion and Extensions
- Keeping UAV in the cross of two beams is tricky.
- Multiple tragets
- 3d instead of 2d
Conclusion
Despite no angular info, high quality tracks.