Combining Bluetooth Low Energy and IEEE 802.15.4 on a Single Chip Solution - A feasibility study

Abstract

This thesis has looked on the feasibility to run Bluetooth Low Energy and IEEE 802.15.4 in parallel on a single-chip solution. Due to the increasing number of small devices that are interconnected and connected to the Internet, also referred to as the "Internet of Things", there is of interest to ensure a reliable network structure between those. Bluetooth Low Energy alone cannot provide such structure, but IEEE 802.15.4 and its related protocols provide functionality such as self-healing mesh and industrial reliability.

In this study, there has been done a research on theory about wireless communication technology and the specified protocols. The focus has been on its lower layers in the stack. This includes its frame structure and how links are established between nodes in the network. Based on the gathered theory, it was created two conceptual frameworks for combining a beacon-enabled IEEE 802.15.4 network and Bluetooth Low Energy.

As implementation platform, Nordic Semiconductor's nRF51 was chosen. Due to no support for the physical layer of IEEE 802.15.4, Atmel's AT86RF231 transceiver was used to imitate support. The Concurrent Timeslot API on Nordic Semiconductor's SoftDevice was used to schedule the protocols in parallel.

The frameworks were tested with different priority parameters on the scheduled timeslots and the Bluetooth module in connection or advertisement. Transmitted IEEE 802.15.4 frames were logged in Wireshark by using a USB-dongle from Atmel. To communicate with the Bluetooth module, Nordic Semiconductor's Master Control Panel and a dedicated USB-dongle were used.

Results and observations from the tests indicates that it is feasible to run both protocols in parallel, but it is challenging to meet the requirements for both protocol's specification. A generalization of suggested solution should therefore be parametrized in order to make it configurable for different scenarios.