This includes electrical noise from other electrical equipment as well as interference from devices using the same 2.4GHz frequency. Least blocking are glass (but not bulletproof), wood and plastics.īlocking can be caused by wireless noise as well and physical obstructions. Next comes water that you might not think would be a problem but, as people are made up of 60% water, bodies blocking Bluetooth signals can be a significant factor. Metal obstructions or metal-based surfaces such as metal-reinforced concrete cause the most blocking followed by other dense building materials such as plaster and concrete.

We often get questions asking what kinds of things can block Bluetooth signals and enquiries about the relative blocking of different materials. Author Support Posted on ApCategories Beacons, Eddystone, iBeacon, RSSI, RSSIStability Finding the Nearest Beacon

Beacons that move more between channels can cause more rapidly varying received signal strength (RSSI). Different radio frequencies experience different constructive and destructive interference at different physical locations. We experienced and mitigated similar behaviour in our LocationEngine™. The channels use different radio frequencies that, in turn, results in fading of the signal at different distances. Moving obstacles, for example people, will cause significant variation in RSSI.īluetooth LE advertising moves pseudo-randomly between radio channels. However, you should keep in mind that environmental factors can often cause variation much larger than the 4 to 6 dBm found in this test. RSSI varying without a change of distance might cause more spurious triggering. Signal stability is more important when you are using the RSSI to infer distance, either directly from the RSSI itself or indirectly via, for example, the iOS immediate, near and far indicators. Firstly those with very stable RSSI and secondly those with an RSSI that had a standard deviation between about 4 and 6 dBm. We found that beacons belonged to one or two groups. Smaller bars are better and represent beacons

Rssi signal