Oh, I believe you. What is static sensing getting you in the kitchen? If you turn it way down does the sensor not stay active with people standing in the kitchen?
Yes, this is a case. Before I was using MS in a Kitchen assuming it is impossible to be motionless
in this area. Well, my wife managed to do something being almost motionless. To deal with this
issue I had to install 2 MS and set lights off delay time to 15min. The same was done in a Bathroom.
(except it was 4 MS and even bidet seat sensing was involved).
Now single mmWave are doing very nice job in both places. And off delay time is down to 1min.
It's is a big deal if you're unaware that it's possible. If you don't know something is possible, you're not going to know to look for it if you're troubleshooting activations when there is no one in the room or next room in front of it. A central purpose of this forum is to make it easier for folks to adopt and use HA. There are a lot of people w/out experience w/mmWave sensors that are going to come across these topics and aren't going to know/expect that a sensor can sense "backwards," so sharing that info is a very good idea. Last I'll say on this.
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Settle down there camper. I'm not sure I'm taking away your rights or trying to silence you. I'm simply saying for the rest of us we know that most any sensor has bleed and a little sensing 8" behind the Linptech for the most part isn't going to impact much. You are breaking out the big guns here when they are not needed.
Well, I did not test Linptech for back sensing in deep details but square shaped sensor
has about the same sensitivity from both sides (front and back). This makes perfect
sense because internal patch antenna is facing front but has no any shielding from
the back. And that is why putting relatively big metal plate (or plastic covered with
coper foil) behind the sensor makes a difference (but unfortunately does not remove
back sensitivity completely).
Yea, I saw your other thread when you are showing pics of the same location with the 5.8ghz sensor.
How does this one do for you?
As I mentioned before I am/was experimenting with many different mmWave sensors.
Few already thrashed. I am still keeping 2xFP2 (too expensive to trash) but very unlikely
these will be ever used (they produced very unreliable results). I have very good
experience with these square sensors but they don't like C8 altogether. I replaced one
in a Kitchen with Linptech only because Linptech has no pairing problem with C8.
In a Bathroom I will keep a square one because it looks much better (near unnoticeable).
After all these trials I ended up with single Linptech in a Kitchen, single square one in
a Bathroom plus one Linptech and two squares in a spare drawer. Because of very high
back side sensitivity I don't see where these spare sensors could be used.
Cool graphic - what's the scale for distance?
No scale given. —- I would guess that rings are 1/2 meter on 6 meter setting. —-
I put my sensor on one side of an uninsulated drywall wall.
It sensed me on the other side, BUT Motion was not triggered.
Motion was only triggered when I was on the front side (and sides) of the sensor.
The distances reported on the back side, through the wall, were about a meter too far.
Not a rigorous analysis.
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This is only half of it. Unless backside is shielded, patch antenna doesn't know what is front and what is back. And this is a reason why these sensors have backside sensitivity.
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But it seems smart enough that it (appears to) only trip motion from the front.
It makes sense in an apartment I guess. Lots of issues with multi-family with technology. I have maybe the opposite end of the space spectrum. For me a little back side sensing makes no difference. If I mount these on a ceiling, bookshelf, most walls I'm not getting within 8" of the device.
I have 6 different MMwave sensors all sold to be as 24ghz. Half have been 5.8ghz. They all seem to work fine. No pairing issues at all.
So how is this device doing? How do you compare it with the Linptech? That you could configure the radar with Bluetooth seemed attractive.
Thanks for the details. I'm going to join my second Linptech this week and play around w/backside sensing to see what kind of results I get.
This one is not paring with C8. It is sensitive near 360 degrees. It is noisy (reporting distance every sec).
The HA sees it immediately via BT connection and sensor could be configured and used
without any pairing. This means any nearby neighbor with active HA can use it. The BT is enabled by default but I am sure it can be disabled. Because of all the above features I
am not considering to use this one.
But from the other side pair of these little boards is around $8. If BT connection is OK it
could be used just with any 5V PS and requires very small DIY housing.
I considered getting an LD24010B and swapping it into the Limptech or one of the mains models for the board that's already in them. That way I can potentially not have to deal with the baseboard zigbee etc and can control and configure the radar board over bluetooth. If the serial communication is compatible with the baseboard programming or it's really just a drop in replacement maybe I get more control for tuning the radar.
Very good chance it is but I am to...o lazy to dig in deeper in this details.
Could have fooled me 
One thing I noticed on my Limptech that other testing could look out for is after making some configuration changes I lost distance reporting. I had to initialize to get them back. I don't know yet what caused the change.
Well, the actual 24ghz sensors dont penetrate surfaces nearly as easily as the 5ghz sensors. I found that I could eliminate the backside pickup pretty easily using a dense object (in my tests, I used a full roll of 3" gaff tape) or some aluminum foil. This is the Linptech sensor.
The 5.8ghz sensors seem to pick up from the backside much easier and it's also much more difficult to block it.
A real shield for 24ghz mmwave would probably more than the price of of these devices especially when you are trying to keep the device small. There are some magnetic metal impregnated polymer sheet types, but they are over $100 for a 10"x10" square.
For example this kind of thing might be used with a 5.8ghz radar:
