e perimeter of the black cylinder denes a geofence for the nan- cial district of Manhattan, NYC.
Drones are nowadays used by companies, governments as well as organizations – but are expected to revolutionize many areas in the future. From commerce to law enforcement, construction, agriculture, rescue missions, disaster relief and more, these unmanned aerial vehicles come in various sizes and configurations which are either completely autonomous or partially controlled by remote human operators.
The technology is leading to a rapid adoption of drones in many applications, as well as growing interest in using drones for myriad tasks such as applications of information gathering, as well as applications of cargo transport and delivery.
In fact, these two are among the most important tasks, because of the following:
From this, we can conclude that the number of drones in the skies is growing – and the Federal Aviation Administration (FAA) estimates that by 2020 it will grow even more, with more than 3 million drones present in the USA only.
A group of authors is focusing on this massive growth of drones and seeing it as a critical challenge. In their paper, they focus on UAV traffic management and the need for geofencing in the sky, where herding drones are complementing with technologies such as the blockchain and 5G.
As the authors note in the paper, the geofencing use for drones are set to define the limits of a geographical space.
“Often, geofencing is used to define an area on a 2-dimensional map, e.g., to provide notifications when a cellular device enters or leaves the defined area. However, in the case of air-traffic, there is a need to define constraints in a 3-dimensional space.”
Obviously, flying objects such as drones need to keep a safe distance from buildings, trees and other drones as obstacles. This is why the authors promote two types of geofences – ones which define the boundaries of a flight space and the ones which aim to prevent aerial vehicles from entering a certain space.
The perimeter of the black cylinder defines a geofence for the financial district of Manhattan, NYC
The green line is a planned flight trajectory. The gray buffer defines the flight zone for the aircraft.
Drones fly in their allocated space. Positioning and geofences are supported by 5G antennas and GPS.
In traffic management, drones are allocating a flight space for the time of the flight to each drone, according to the constraints defined by the geofences and the buffers around the flight trajectories.
The authors here focus on centralized as well as decentralized traffic management and suggest an approach to “coordinate the flight-space allocation in a decentralized way is by using a blockchain – as a decentralized, tamper-proof and transparent ledger, managed by peers, connected by a peer-to-peer network.”
A blockchain for drones can be used to reach consensus in a decentralized environment, where each drone would try to add to the blockchain a request for the space required for its mission at the time of the flight.
On the other hand, the authors also propose a method that uses 5G networks for positioning, especially in urban areas where geofencing can be implemented effectively. As they originally put it:
“We envision the use of the emerging 5G networking technology for that. 5G networking technology is the next generation of cellular networks. It is designed to provide much higher speed—larger bandwidth and smaller latency—higher reliability and the ability to serve a larger number of users, in comparison to 4G. To do that, the radio spectrum is partitioned into bands, with different frequencies—from low to extremely high.”
The general conclusion is again revolved around the problem of air traffic control for a sky crowded with drones. Given the variety of current and potential uses of drones and the rapid growth in the number, there is an acute need to manage drone traffic.
Therefore, the authors suggest a system that is based on a partition of the sky using geofences – and a system that “can allocate the flight space for drones and support admission control.”
Citation: “Geofences in the sky: herding drones with blockchains and 5G”, Tamraparni Dasu, Yaron Kanza, and Divesh Srivastava, SIGSPATIAL ’18 Proceedings of the 26th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, Pages 73-76, https://dl.acm.org/citation.cfm?id=3274914