BRIDGING THE DIGITAL DIVIDE: ACCESS TO SATELLITE BROADBAND CONNECTIVITY
Imagine a mega-constellation of thousands of tiny low Earth orbit (LEO) satellites blanketing the Earth and beaming broadband signals to populations in rural, remote, and underserved regions. From the mountains of Nepal to the plains of Africa, envision fast, reliable satellite broadband connectivity providing or improving digital access for millions of people.
Currently, the pricing structure of these networks is too expensive for most rural populations, and satellite broadband is limited to a few markets where terrestrial solutions don’t work. Although many uncertainties remain, costs will continue to evolve with technological advances and economies of scale. If constellation providers can offer competitive pricing, consumer demand could soar, and LEOs could bring access to satellite broadband connectivity across the globe.
While cable, fiber optic, and 5G mobile fuel the next generation of digital infrastructure on Earth, LEO satellite constellations are projected, in the long run, to play a key role in supporting the global connectivity ecosystem when fully operational. LEOs are expected to stimulate economic growth, improve access to education and healthcare, and help close the digital divide.
LEOs will expand high speed internet access to landlocked developing countries, developing states, and hard-to-reach remote and rural areas. Island nations can be given a pathway via satellite to broadband internet and circumvent the enormous cost of building a submarine cable system carrying international traffic. Satellites can also provide backbone connectivity to mobile 5G cellular networks while enabling critical communication access for those most in need.
The Economics of Fiber Cable vs. Satellite
Providing broadband internet to millions of customers in a heavily populated urban environment is a lucrative business. However, building and maintaining terrestrial expansion to more sparsely populated regions is expensive. Return on investment rarely offsets the cost. Thus, terrestrial build-out to rural and remote areas can lag for years, even decades.
“For geographies without direct access to fiber optic cable infrastructure or at great distances from high capacity bandwidth, satellite connectivity is the only option available.”
Asian Development Bank (ABS)1
No matter the technology, there’s an infrastructure cost to build and operate the core network, ongoing customer equipment costs, and recurring subscriber costs for the customer.
Local, state and national funding programs can help cover some terrestrial-based infrastructure costs and service plans. The FCC’s Affordable Connectivity Program, the USDA’s ReConnect Rural Broadband Program, and the U.S. Bipartisan Infrastructure Bill provide billions of dollars to individual states, operators for infrastructure expansion, and subsidy programs to low income families. But the size and scope of the terrestrial-based plans are limited. Another, more comprehensive solution is needed.
Today, low Earth orbit (LEO) satellites are the focus of intense interest and capital investment. Mega-constellations of up to 12,000 LEO satellites are in the early stages of deployment. “If current satellite internet proposals become a reality, about 50,000 active satellites will orbit overhead within ten years,” cited McKinsey in a 2020 analysis of the commercial space industry.2
- 90% of all satellites are LEOs
- 7,500 LEOs now circle Earth (Sept. 2021)
- Orbit of 160 km to 2,000 km (60 times closer than geostationary equatorial orbits (GEOs))
- Orbit period of 88 min to 127 min (depending on altitude)
WHY SO MANY SATELLITES?
Low Earth orbit satellites pass overhead quickly, providing connectivity over a small geographic area for a brief time. The advantage of the LEO’s low orbit (2,000 km high) vs. GEO’s Earth orbit (35,000 km high) is lower latency and the subsequent reduction in the time it takes for a signal to travel round trip from ground to satellite and back down again. A lower latency reduces lag and permits faster response times for communications. However, the current generation of satellite broadband will not support the 3GPP low latency spec requirements needed for immersive gaming, video calls, streaming video, or much touted innovations such as remote robotic surgery and autonomous driving.
Mega-Constellation of Satellites
LEO constellations require an extensive network of hundreds or thousands of satellites to attain robust global coverage. Rural and remote communities, the areas most targeted by the constellations, are often the least able to afford the cost of the satellite dish equipment and data plans, necessitating government programs and subsidies as well as new business models that require deeper collaboration and standards, and interoperable, open architecture among all the players.
SPACE BUSINESS IN TRANSITION
Today’s commercial space business is moving away from yesteryear’s low volume, government-funded, one-off programs to large-scale commercial ventures employing reusable rockets and smaller, cheaper LEOs. The industry seeks adaptable and flexible solutions that are cost-effective and capable of meeting accelerated demand. New players, applications, business models, and government programs enable a dynamic competitive commercial space ecosystem.
What’s Driving the Commercial Space Satellite Industry
- Global coverage for rural, remote, and urban areas
- A drive to close the digital divide
- Cheaper launch and ground station costs smaller, lighter, and cheaper satellites
- Modern IC technology
- Advanced phased array functionality
- Development of large mega-constellations
“New satellite constellations are on the cusp of deployment, but their long-term success hinges on substantial cost reductions.”
Advances in design, manufacturing, and standardization have had the most significant effect on the satellite industry, enabling faster and more flexible deployment. Whether costs ultimately come down enough to make satellite broadband connectivity affordable is still unclear.
Reusable Rockets and Smaller Satellites
LEO satellite launches are rapidly increasing while costs are shrinking. The decreased launch cost results from a vertically integrated launch vehicle production line that is more reliable, adaptable, and efficient. With the combined savings from ride-sharing, booster reuse, and lower orbit satellite placement, the price per satellite for launch is now as little as a million dollars.
Image Courtesy NASA
Tailoring Reliability and Rad-Hardening
High reliability, radiation-tolerant semiconductors were initially required to survive for decades in the extreme conditions of space aboard NASA missions to the planets and high Earth orbit GEO satellites. But LEO satellite markets have relaxed requirements, with durations of only a few years and lower earth orbits that have reduced levels of radiation exposure.
“Today’s high volume commercial space market cannot afford, nor do they often require the more costly 'classic' components,” said Chris Chipman, Product Line Director, Aerospace, Defense and RF Products, ADI. “They can realize cost savings with ADI’s commercial-off-the-shelf (COTS) components.” Benefits include access to advanced technologies, higher levels of integration and performance, and superior size, weight, and power (SWaP). Commercial space low (CSL) offers testing and screening suitable for constellations orbiting in lower radiation environments for those requiring more protection.
Reducing Ground Stations Costs
Ground stations form the core of global networks, and a satellite dish must be within 500 miles of a ground station to access the internet. Thus, an extensive network of internet-connected ground stations is required. Reducing the cost or the number of ground stations needed is critical for an industry on a mission to bring connectivity to underserved populations in rural and remote areas.
A ground station broadcasts internet signals to a LEO satellite.
A satellite relays the signal to numerous points on Earth, employing electronically steered, phased array beamforming technology.
A satellite dish uses a passive phased array antenna to track the rapidly moving satellites and their signals as they pass overhead.
Using laser links to reduce the number of ground stations required
LEOs with laser links or optical intersatellite lasers (OISL) can reduce the number of ground stations needed for global connectivity. Laser links distribute communication traffic and route it around a constellation—between satellites—rather than pinging back and forth between ground stations and space. The routed signal is sent directly to a home antenna.
INCREASING BANDWIDTH AND OPPORTUNITY
“LEOs are forecasted to significantly increase the available internet bandwidth in remote and rural geographies not currently served by fiber optic cables,” according to the 2021 Asian Development Bank report.1 The increased bandwidth could increase economic and social development opportunities in those regions, provided that the private sector companies investing in LEO constellations have identified market opportunities that unlock long-term value to extend service to these regions.
SATELLITE BROADBAND ACCESS: TODAY, TOMORROW, AND BEYOND
Satellite networks can potentially extend the internet’s reach to places that conventional fixed and mobile networks cannot be or where terrestrial-based technologies are not economically viable.
Satellite broadband offers the promise of ubiquitous connectivity and new ways of working and living untethered from cable and fiber connections. Urban students, rural farmers, and people working in remote offshore mining rigs and ships at sea all stand to benefit. Service levels may eventually rival fiber optic cable speed and latency, enabling new applications—yet to be envisioned.
More than a dozen startups are now planning to use small satellites (LEOs) to connect with the internet of things (IoT).3 GSMA Intelligence forecasts that IoT connections, both consumer and those used in industry, will reach almost 25 billion globally by 2025.4
Space-based communications networks must integrate seamlessly with terrestrial networks to maximize their effectiveness. Significant investment is required in space communications technology and terrestrial wireline infrastructure between satellite ground stations, service providers, and data centers.
What to Expect
Given satellites’ power to transform the communications landscape and bridge the digital divide, internet providers, manufacturers, and companies from all walks of industry should consider how to prepare for the future today and investigate how to best tap into opportunities presented by the new communications frontier.
How ADI Helps Satellite Providers
As the need for data bandwidths increases, the burden to deliver end-to-end performance is becoming more complex for operators of LEO satellite networks. Speed-to-market and ease of integration are more critical than ever. The electronic content of satellites is expanding exponentially. New ambitious design solutions require reduced size, weight, power, and cost.
Analog Devices has the industry’s broadest portfolio. It gives commercial space satellite providers everything they need to simplify architecture, accelerate design, and optimize at semiconductor and integrated subsystem levels. ADI offers a complete signal chain for phased array antennae from the data converter and transceiver ICs up to the RF front end. We help customers design phased array antenna solutions where smaller components work optimally together, reducing SWaP and increasing performance.
1John Garrity and Arndt Husar. “Digital Connectivity and Low Earth Orbit Satellite Constellations: Opportunities for Asia and the Pacific.” Asia Development Bank, April, 2021
2Chris Daehnick, Isabelle Klinghoffer, Ben Maritz, and Bill Wiseman. “Large LEO satellite constellations: Will it be different this time?" McKinsey, May 4, 2020
3Christopher Mims. “Elon Musk and Amazon Are Battling to Put Satellite Internet in Your Backyard.” The Wall Street Journal, March 20, 2021
4 Sylwia Kechich. “IoT Connections Forecast: The Rise of Enterprise.” GSMA, December 16, 2019