Received Signal Strength Indicator (RSSI) is another option, but Wi-Fi vendors handle it inconsistently and with varying ...

A measurement of the strength of a radio signal being received. In RFID, RSSI is used to determine a tag’s distance, as the signal is stronger from a tag that is closer to the reader antenna.

You can use any of these free tools to measure Wi-Fi signal strength, but make sure to first go through all the features, limitations, and ease of use. Apart from dBm, RSSI is also another unit to ...

while the other picked up what was left of the signal (the received signal strength or RSSI) on the other side of the walls. The result is a pretty decent image of what's inside the building.