AWR1642: RF Loss through Glass (car windows)

Regarding the transmissivity of glass (and smoke):  In the link you sent me the object being detected was very close to the radar (10-40cm).  At this distance, the return signal should be huge, which means you could tolerate a lot of RF attenuation and still see the signal.  It would be a more realistic test if the object were near the detection limit of the radar, or at least some point more than 5m away.  In other words, this test data does not quantify the amount of loss the signal has through glass or smoke.  Do you know if there is any other test data that shows a more “real world” measurement?  I really doubt people are using this radar primarily to detect motion of objects which are only 6-12” away, other than for gesture detection.  

Those plots are quite interesting.  However, none of them provide the “baseline” case, which would so the received signal strength when there is no blocking object between the radar and the object of interest.  In the link you sent, the experimenters did a great job of describing how they test the unobscured object, and the add the obscuration.  In this second article, they just go straight to the obscured object, with no regard for a baseline comparison point.  So the reader has no way of quantifying the loss due to obscuration.  Although it does provide great insight into the amount of refraction vs. reflection for the radar signal.

Do we have a general reference that can be used which has the reflectivity, penetration & absorption of various materials? Also, do we have any guide, best practice, or other information regarding the packaging/enclosure of mmWave radar antennas.

Hi Team,

Any update?

Thanks,

Siby 

Hello Siby,
The attenuation of the 80Ghz RF signal would depend on the exact material used and the manufacturing process used. You can find online material on studies done on different materials, one reference paper is : arxiv.org/.../1703.08030.pdf where common indoor materials like glass, wall, door , steel etc. have been studied for a 73Ghz signal. The performance should be very close for the 80Ghz signal as well.

Regards,
Vivek

Hi Vivek,

Thanks for the article. However, this doesn't touch upon the question of "Best practices/guide or other information regarding packaging/enclosure of mmWave radar antennas"?

Please forward that information as well.