BLE signal spikes ?

[MuRa]

Hello all

the BLE module with the nRF52820 is programmed with a ble_app_uart_pca100e example from the nRF5SDK ver 17.1.0, according to the RSSI graph it seems it works , however, how to explain the spikes in the signal? Have a look at the attached pic. 

Any ideas? Where to get a good reference on the signal strength , like dBm , what does that actually mean?

Best.

[ketiljo]

The RSSI value will fluctuate a lot depending on reflections. If you move either the TX or the RX or something in between that the signals reflects off, the properties will change and you will get a different RSSI level.

[MuRa]

Thanks for your input ketiljo , so, I guess  if I leave the "device" , namely the receiver and transmitter alone, put on the table... then the RSSI value will become stable?

[ketiljo]

As long as you or anything else around you moves as well that is.