Neighbor Discovery in Wireless Networks: Moving from two to the Multi-Device and Asymmetric Case

• Applicant: Dr.-Ing. Philipp Heinrich Kindt
• Subject Area: Security and Dependability, Operating-, Communication- and Distributed Systems
• Term: from 2022 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 492661503

The Internet of Things relies on energy-efficient wireless communications for achieving sufficiently long battery runtimes, or for being able to power devices using energy harvesting. However, the procedure for establishing a first wireless contact, called neighbor discovery, remains to be very energy-hungry. This particularly aggravates applications, in which such a procedure needs to be carried out continuously for detecting new devices in the environment.For establishing a first contact, every device transmits packets regularly to the channel, and regularly schedules reception windows for detecting incoming transmissions from other devices. For saving energy, the devices sleep whenever they don't participate in the communication. As soon as a packet is sent while another device is carrying out a reception window, a first contact has been established. The main goal is to minimize the latency until which a first contact can be established in the worst-case. Towards this, the schedule of packets and reception windows needs to be optimized. For the case of one transmitter and one receiver, an optimal solution is known for this problem. However, when multiple devices discover each other simultaneously, colliding packets become predominant in this procedure and existing solutions are no longer optimal. Furthermore, even for the case of only two devices, no optimal protocols that allow each device to adjust its energy-budget autonomously are known. Both scenarios are highly relevant in the Internet of Things, with its growing number of heterogeneous devices with different energy requirements. Goal of this project is creating the theoretical foundations for an efficient neighbor discovery procedure in such scenarios. Based thereupon, we develop practical protocols with a significantly higher performance than existing solutions. We furthermore evaluate our results using discrete event simulations and real-world experiments using wireless radio hardware.

• DFG Programme: Research Grants