In simplest terms, RSSI is the measure of strength of a radio signal in a wireless environment. It is the measured in decibel milliwatts (dbm).
As a rule of thumb, the higher the RSSI, the stronger the signal. RSSI tells us whether the signal is getting stronger or weaker and we can use this fact to our advantage by approximating the proximity of the broadcasting Bluetooth Low Energy device.
Since you now understand what RSSI is, then, not going into too much detail, we can safely say that, if given a list of RSSI values, then just by looking at these values we can already guess whether the broadcasting BLE device is nearby or far away. We will elaborate on this fact through the following RSSI values:
Figure 1: Typical RSSI values
Can you already guess what do these RSSI values mean?
Note
Don't worry if you do not understand how these RSSI values were generated; we will be covering that in detail when we design the tracking app.
Well, first things first: if you haven't already...