There is no way to get this information directly using the Accuware Wi-Fi Location Monitor or Bluetooth Beacon Tracker API. Despite this, there is a simple formula called Haversine formula, which returns the distance in meters between two points expressed in lat/lng. Using the Haversine formula you can directly calculate the distances between the location of any device detected and any node. There are countless implementations in different programming languages of the Havarsine formula. At this link you can find an online implementation of the Haversine formula.