BluetoothProximity

This is a basic iOS application that was built to log information from the Bluetooth receiver and other sensors on iPhones. The purpose of logging the data is to understand the Bluetooth radio propagation channel between devices in everyday use. By collecting this data, algorithms can be developed that use knowledge of the phone's state, along with the Bluetooth Received Signal Strength Indicator (RSSI), to determine if a Bluetooth device is close or far away.

At a basic level, the RSSI decreases proportionally to the square of the distance between the transmitter and receiver. With knowledge of the transmitter power, the RSSI gives insight into the path loss, and thus the range. However, when a phone is in a pocket or masked by the body, the path loss can be much larger. By using this app to collect data in different scenarios, we hope to design a proximity detector with a high probably of detection and low probability of false alarm.

On first launch, approve the use of Bluetooth and allow location and motion services (logging GPS and other sensors can by optionally configured). If you're having issues recording data, make sure that you've enabled access to location services, Bluetooth, and motion & fitness (under the privacy settings of your phone).