Solutions for implementing a Multihop Topology for Bluetooth Low Energy

2015

While the Bluetooth Low Energy standard is able to provide unmatched accessibility and

power consumption, it lacks proper support for multihop topologies, which severely limits its

applicability in scenarios where the network is expected to cover distances beyond the reach

of a single device's radio range.

This thesis addresses the topology-shortcoming in the Bluetooth Low Energy standard by

analyzing challenges related to the design of a mesh network topology extension for the

existing standard, and presents solutions for an implementation.

During the design process, a wireless network simulator is designed and implemented, in

order to provide the candidate with an additional tool for development. The simulator is

published as an open source project on the repository hosting website GitHub, in hopes of

future usage in other similar design processes. The simulator becomes a central part of the

design process during development, as it provides fast feedback to the candidate regarding

the quality of the various solutions attempted. At the end of the design phase of the project,

the simulator features a full-

edged implementation of the design, which is published along

with the simulator.

As part of the work conducted to qualify various approaches to network structure, a network

backbone formation algorithm is designed and compared to existing solutions for the subject.

The algorithm performs well compared to its competitors, but fails to provide consistent

network wide backbone connectivity.

Towards the end of the thesis work, the solution design is implemented for the nRF51 series

microcontroller by Nordic Semiconductor. The nRF51 implementation is focused on providing

a solid basis for future development, and is expected to be extended upon during the

candidate's future cooperation with Nordic Semiconductor.

While the nal design presented in the thesis paper fails to meet the initial expectations to

functionality, which were proven far too ambitious for the time allocated for the project, the

candidate is condent that the solutions that are implemented provides all the performance

and functionality that can be expect from the solution, and will be able to act as a basis for

a design that could compete with all existing solutions for the intended application areas.

This thesis work is conducted in cooperation with Nordic Semiconductor ASA, represented

by David Edwin, and builds upon the candidate's prestudy on the topic.

NTNU