Predicting the Channel Access of Bluetooth Low Energy

TL;DR

This paper introduces a passive listening method to estimate and predict BLE device channel access, enabling other networks to avoid collisions in crowded 2.4 GHz environments.

Contribution

It presents a novel algorithm to identify BLE connections, reconstruct their parameters, and predict future channel access without prior knowledge.

Findings

Successfully identified unknown BLE connections

Reconstructed connection parameters accurately

Predicted future channel access to reduce collisions

Abstract

Bluetooth Low Energy (BLE) is one of the key enablers for low-power and low-cost applications in consumer electronics and the Internet of Things. The latest features such as audio and direction finding will introduce more and more devices that rely on BLE for communication. However, like many other wireless standards, BLE relies on the unlicensed 2.4 GHz frequency band where the spectrum is already very crowded and a channel access without collisions with other devices is difficult to guarantee. For applications with high reliability requirements, it will be beneficial to actively consider channel access from other devices or standards. In this work, we present an approach to estimate the connection parameters of multiple BLE connections outside our control and knowledge by passively listening to the channel. With this, we are able to predict future channel access of these BLE connections that can be used by other wireless networks to avoid collisions. We show the applicability of our algorithm with measurements from which we are able to identify unknown BLE connections, reconstruct their specific connection parameters, and predict their future channel access.