In recent years, cellular and LTE communications have become attractive key enablers for BVLOS (beyond visual line of sight) UAV (unmanned aerial vehicle) command, control and communications. Many drone developers and service providers are looking to cellular connectivity to fill in the gaps where other wireless technologies may be unable to serve sophisticated drone applications that require unprecedented bandwidth and range.
In many parts of the world, particularly in urban and industrial regions, cellular networks provide a high degree of coverage, and drones operating within certain areas have excellent connectivity potential. Cellular networks operate on regulated portions of the spectrum, and so providers must run and maintain their networks according to strict regulations. This ensures a high degree of reliability, which is essential for the acceleration of commercial drone operations, and especially for the evolution of BVLOS.
5G vs 4G
5G connectivity offers a significant increase in data throughput over 4G, as well as substantially reduced latency. The use of 5G massively improves the utility of small SWaP (size, weight and power) drones, which lack the onboard resources to perform the computationally intensive calculations required for sophisticated AI-enabled applications such as image classification. With the enhanced bandwidth and response time provided by 5G, drones will be able to shift this processing burden to cloud computing centers located on the edge of the network. These computers can take care of the “heavy-lift” processing and return the results to the drone even before it lands.
The challenges of LTE drone connectivity
While cellular drone connectivity shows an amazing potential to revolutionize the industry, there are a number of challenges that still need to be resolved. According to Ericsson, less than 15% of the world’s population was served by 5G at the end of 2020, and even 4G is not completely ubiquitous, with 95% population coverage not expected until 2027. This means that long-range BVLOS drone missions require a solution that can manage multiple cellular networks as well as a backup RF system, in order to cover all the bases when cellular “dead zones” are encountered.
Another challenge is that of interference. While drones that fly at altitudes above buildings, trees and other obstacles can “see” more cellular base stations due to the lack of obstacles, this enhanced signal level comes at the cost of increased interference. This interference is due to the increased likelihood of the drone now having line of sight to non-serving base stations as well as the serving station.
A potential solution to both these problems is the use of a 3D map of cellular reception levels that allows mission planners to predict the communications conditions that will be encountered by the drone during the flight. Detailed information about the presence of network connectivity and the signal strength, and how these change with altitude as well as horizontal travel, could be used to plan successful drone missions. While the industry waits for near-ubiquitous LTE coverage, this information can be used by autonomous and BVLOS drones to successfully carry out a wide range of missions, such as delivery, utility drone inspection and mapping, with the greatest possible safety.
The state of the art in cellular mapping
While cellular reception mapping for drones is currently very much in its infancy, and the data for most areas is unlikely to be available for some time, network providers and drone companies are beginning to put in the work. Examples include:
-Vodafone has trialed its Radio Positioning System (RPS) for drones in Barcelona, with the aim of creating an aerial mobile coverage map of the city.
-Skyward and Verizon are working together to capture data on how drones connect to the Verizon wireless network in the United States under a variety of conditions and operational ranges, including BVLOS.
– IBM’s “Project Skittles” aims to develop a visual representation of how connectivity strength for wireless technologies such as 4G and 5G vary across large spaces.
-Ericsson has deployed drone-mounted network scanners in Finland to characterize levels of 5G coverage, with the data showing highly repeatable results.
Harnessing the power of cellular drone connectivity with Halo
If you are looking to take advantage of cellular connectivity to power your current or future BVLOS drone operations, Elsight’s Halo is the ideal connectivity platform. Able to utilize up to four different LTE/5G carriers simultaneously, Halo offers advanced bonding technology that aggregates these multiple cellular links together with other IP links over Wi-Fi or Ethernet. The result is a robust drone command and control (C2) and data solution that constantly checks for compromised channels arising from loss of reception and automatically reroutes to the most suitable channel for your application’s particular needs.
Halo has also added a new state-of-the-art feature, cellular mapping, that allows users to map and record cellular reception levels simultaneously for all LTE/5G networks in use by the device. This makes it an indispensable tool for drone operators planning flight routes based on cellular reception levels, as well as for network carriers looking to characterize and adjust their reception levels to better serve the UAV industry.