Satellite and Mobile Networks: A battle of bits
The 5G revolution
5G is the next generation of mobile and wireless broadband technology expected to overtake 4G in terms of latency, number of devices connected, access speeds, remote coverage availability as well as energy consumption. Large-scale adoption of 5G with the high number of connected devices at an ultra-fast and highly reliable connectivity will reduce the time it takes for multiple sensors to collectively take decisions to the order of a few milliseconds enabling technologies like autonomous car, virtual reality, artificial intelligence and smart cities that can only be fully implemented once the data network catches up with the technological advancements.
Satellites for 5G with a focus on mobility markets
While much emphasis is being laid on the terrestrial means of coverage in the deployment of 5G, satellite technology and high-altitude platform systems will also play a pivotal role to complement the fixed and terrestrial backhaul networks. Realistically, terrestrial 5G will not be able to reach the coverage of 4G even in the next decade, with the requirement of a much denser network of base stations which will be achieved in large part via small cells. All industry analysts agree that marine areas beyond the reach of terrestrial networks will continue to rely on satellites, feeding the maritime and aeronautical markets. The same applies for remote underserved regions where satellites can be used to connect 5G base stations to small cell stations in rural communities.
With increasingly higher data rates (of up to 1 Gbps) and lower latencies, satellites can be integrated into the 5G solution to address some of the key challenges in providing truly ubiquitous coverage as well as supporting IoT. However, there are some complications with this integration. Satellites orbiting the Earth are located at a much larger radius than the typical distance between a cell phone and its serving base stations, introducing delays in data transmission. The long distance also adds pressure to the link budget and despite powerful antennas and power amplifiers, the user equipment will most likely have to deal with a lower signal-to-noise ratio. This would require better coding and modulation choices which in turn might lower the data rate further. LEO orbits do a better job at tackling latency but the shorter orbiting period requires frequent switchover from one satellite to another causing disruptions in data transfers, and ultimately implying the need for additional redundancies in the system.
Stepping away from the technical challenges are competitors with the presence of cellular technologies in the aeronautical market. For continental flights, Air-to-Ground (ATG) networks have been active for several years, with Gogo as the leading provider in the North American market. However, an increasing number of airlines and service providers have been reconsidering their connectivity options following low-speed performances, prompting Gogo to diversify its offerings to include satellite services with better data rates, branded as its 2Ku inflight connectivity solution and known to have been sold to Delta and American Airlines. Gogo also concluded an agreement for the lease of HTS capacity onboard Eutelsat 10B as part of a multi-year contract signed in October 2019 to bolster high-speed in-flight connectivity over the Middle East (with peak antenna speeds of 70 Mbps), immediately leading to Qatar Airways’ commitment in November 2019 to the installation of 2Ku on 70 of its aircrafts, allowing for occasional video streaming and an adequate level of browsing as early as 2020.
According to Euroconsult’s estimates, as an increasing number of operators get into the emerging HTS market in the coming years, the total number of ATG terminals onboard commercial aircrafts is projected to go down with a 5-year CAGR of -1%, primarily driven by a sharp decline of -7% in the North American market where they will be replaced by VSAT terminals whose higher data rates will allow airlines to meet the growing connectivity needs of passengers. With a smaller data rate requirement per aircraft, ATG remains a promising option for the business aviation vertical, as the total number of terminals is projected to reach upwards of 10,000 by 2028, corresponding to a 10-year CAGR of 7.1%. North America will remain the largest business aviation market with its long established ATG infrastructure, followed by Europe through the expansion of the European Aviation Network, an integrated satellite and ATG network developed by Deutsche Telekom and Inmarsat.
Despite the multiple requirements that have been flooding the upcoming 5G network, it is clear that no single technology can sustainably meet all these conditions, neither are they all required for every single 5G application. Quite the reverse, several organisations have acknowledged that what is needed from 5G is to successfully adapt to the requirements of different applications. There are times when the latency benchmark will restrict satellite usage but not all applications are critically latency sensitive. Satellites offer advantages that are critical to 5G attaining its goals of built-in redundancy, cost-effectiveness, and especially remote area coverage to maintain communications for maritime, aeronautical and other transportation networks.
Bridging the gap between theory and implementation
To prove that the two technologies do not necessarily have to be at odds with each other, Gilat announced earlier this year that it has successfully demonstrated the delivery of 5G services via one of Telesat’s Phase 1 LEO satellite through a high throughput modem. Web browsing, video chatting, simultaneous streaming of 8K video, and transfer of 4K video to the edge of the 5G network were part of the experiment. More recently, the Korean telco KT Corp announced that its satellite-operating subsidiary KT SAT has successfully executed a 5G data transmission experiment using satellite connection. The operator transmitted real-time streaming data and live video footage from its Kumsan Satellite Service Center to the 5G edge cloud by using satellite backhaul links. These demonstrations highlight the possibility of achieving seamless and high-performance connectivity that meets the stringent 5G standards and pave the way for future collaboration between satellite operators and key 5G stakeholders.
Euroconsult. (September 2019). PROSPECTS FOR IN-FLIGHT ENTERTAINMENT AND CONNECTIVITY, 7th edition. Paris: Euroconsult.
Winee Lutchoomun is a Consultant at Euroconsult with expertise in satellite connectivity. Her daily activities include research, data analysis and contribution to consulting missions.