I performed multiple setups with 4 anchors and 6 anchors system but have the same results. Please help me understand the following. If I put the tag on my chest and walk in the area (40m x 40m) I get missing data and with high variations in the path, but If I hold the tag 4-5 inches away from my chest I get perfect results and too many position-points- WHY?. Do you think it is because the body absorbs the signal OR when I move tag further it is able to maintain a line of sight with anchors efficiently?
This is related to LOS (Line of Sight) and Non LOS.
Some reading on the topic…Have a look here - The APS0006 Series talks about this.
I was able to understand 10-15% of the content ::). I cannot understand that this is not 100% NLOS case as tag can always see at least one anchor. What happens if I install 16 anchors in 40m x 40 meter area such that at any time, at any angle each tag sees at least three anchors. Would it overcome the behavior?
If you google “EM ENERGY ABSORPTION IN THE HUMAN BODY
TISSUES DUE TO UWB ANTENNAS” you find a paper from M. Klemm and G. Troester.
It basically says (at least, that’s what i conclude from it) that if the antenna is very close to the body more of the signal is absorbed by the body and thus your signal strength degrades