Bluetooth Proximity Detection

Python code for getting the RSSI value of a Bluetooth device by address. Based on the value returned, can determine the proximity of the device.

This code was adapted from this Github by Daniel Agar.

Requirements

This code requires the bluetooth and python-bluez modules to be installed. On Ubuntu/Debian systems, this can usually be done with the following commands:

sudo apt-get install bluetooth
sudo apt-get install python-bluez

Note: Your system must also have a Bluetooth adapter.

Installation

git clone https://github.com/ewenchou/bluetooth-proximity.git
cd bluetooth-proximity
sudo python setup.py install

Examples

test_address.py

This is a simple script to scan and output the RSSI value of a Bluetooth address in a loop. This can be used to test if the code is working on your setup and also to output the detected RSSI values as you move your Bluetooth device closer/further from the Bluetooth adapter.

Use Ctrl + C to exit the script or wait until number of loops has finished.

python test_address.py <bluetooth-address> [number-of-loops]

bluetooth_scanner.py

An example script that uses threads to scan for bluetooth addresses in a loop and invokes a callback function when the RSSI value is within a specified threshold.

Edit the script and set the BT_ADDR_LIST variable to the list of bluetooth addresses to scan.

Use Ctrl + C to exit the script.

python bluetooth_scanner.py

lnsm.py (Log Normal Shadowing Model)

An example script to scan & output the distance between two bluetooth devices using the RSSI value . The distance between the two devices is calculated using the Log-Normal Shadowing Model/Log-Distance Pathloss Model.

Use Ctrl + C to exit the script or wait until number of loops has finished. Recommended number of loops = 30

python lnsm.py <bluetooth-address> [number-of-loops]

Notes

• The RSSI values returned will differ depending on your Bluetooth devices and your surroundings (e.g. are there walls/obstructions, multiple floors, etc).
• Use the test script mentioned above to see what values are returned in your setup.
• RSSI values may be positive or negative integers. You can use the absolute value (i.e. always positive) if you see both.