The talisman will make use of BlueTooth for both communication bridged to the internet and also to detect the proximity of the talisman to beacon units.
To confirm the use of the RSSI (Radio Spectrum Signal Strength) and determine the available accuracy and range a device was built.
The Bluetooth Proximity device has an internal microprocessor, BlueTooth Module and a 2 line LCD.
After starting, each row in the LCD shows the signal strength reading for each of two example beacons. This shows that it is possible to detect when the talisman is within proximity of one or more beacon units.
The beacon units are very simple and contain a low cost bluetooth module that is simply permanently powered via a wall plug pack or other USB power source. There is no requirement for the beacon to contain any microprocessor or to connect to the internet.
To test the proof of concept the two beacon should be plugged into a USB power source, and placed in two rooms around a house. Then the LCD display unit should also be powered via the USB cable and moved around to allow observing the possible detection range and accuracy.