Is Laser Communications the Key to the Future of Satellite and NTN Networks?

In recent years, a growing technology being implemented in Satellite Communications (SatCom) involves using the optical spectrum (1 Terahertz (THz)), which transmits information through lasers and optical telescopes instead of radio waves and transmitters. This technology, known as Laser Communications (lasercom) or Free-Space Optical (FSO) communications, allows for higher data rates. As a result, missions can send and receive more information in a single transmission compared to traditional radio wave systems. The National Aeronautics and Space Administration (NASA) estimates that data rates for FSO are 40X higher compared to traditional Radio Frequency (RF( communication, particularly when comparing the Ku-band 5 Gigabits per Second (Gbps)) to optical (200 Gbps) bandwidth.

While FSO communications has been gradually developed over the past 30 years, it has been commercial satellite network Starlink's successful implementation of Optical Inter-Satellite Links (OISLs) routing network traffic that has energized the market. As a result, OISLs have now become highly sought after for new Low Earth Orbit (LEO) constellations, such as Amazon’s Project Kuiper, Telesat Lightspeed, the European Union’s (EU) Infrastructure for Resilience, Interconnectivity and Security by Satellite (IRIS2), and the Space Development Agency’s (SDA) Proliferated Warfighter Space Architecture (PWSA). Even emerging Non-Terrestrial Network (NTN) platforms, such as High-Altitude Platform Systems (HAPS) operating at 18-Kilometer (km) to 25-km altitudes in the stratosphere, are being explored to support the emergence of Space-Air-Ground Integrated Networks (SAGINs) leveraging FSO communications, considered an indispensable component of potential future 6G networks.

The development and use case expansion of FSO communications for NTNs has become a promising evolutionary path toward layered, multi-path low-latency communications via SAGINs. In this respect, it is anticipated that 6G networks will leverage a converged terrestrial and NTN architecture, where satellites connect user devices to the telco core network. In this way, optical connections will be crucial for transferring data between connected satellites and HAPS, ensuring seamless handoff to ground networks. Critically, this new non-terrestrial transport layer helps build redundancy and offers a potential alternative to subsea cables, with the added benefit of lowering NTN Capital Expenditure (CAPEX) due to reduced ground station infrastructure requirements and enhanced data transport capabilities. Moreover, the ability to support new emerging communications technologies over NTNs, such as Quantum Key Distribution (QKD) and Post-Quantum Cryptography (PQC), makes the deployment of satellite optical networks increasingly attractive.

While FSO communications is susceptible to atmospheric turbulence, orientation errors, and beam scintillation effects, as noted in ABI Insight “Embracing Light: The Satellite Industry’s Transition from RF to Optical,” the industry is exploring remedies through software-defined network selection schemes for HAPS, ground stations, and interconnected satellites. Such a scheme would enable NTN optical networks to select the most suitable platform in space, in the air, and on the ground to connect and overcome impacts to connectivity. Such a network would require significant optical space and air assets, and a proliferated optical ground network to support ground station selection capabilities. While numerous companies, such as Mynaric (Germany), Cailabs (France), BridgeComm (United States), and Laser Light Communications (United States) are emerging to support direct-to-Earth communications for optical communications, Optical Ground Terminals (OGTs) remain an emerging technology.

Despite these factors, NTN networks continue to deploy satellite-based regenerative and optical payloads as the benefits and revenue potential from enhanced data transport are significant for mesh networking and delivering Direct-to-Cellular (D2C), broadband, and Internet of Things (IoT) applications. The impact of optical communications in NTNs is further explored in ABI Research’s latest report, The Future of Satellite Networking: Laser Communications in Space (PT-2610), where it is estimated that end-user revenue generated from transporting network traffic over laser satellite networks will equate to US$15.2 billion by 2027.

With optical communication links able to serve the unique connectivity needs of commercial and defense sectors, ABI Research projects that satellites with lasercom payloads will see a surge in deployments from over 4,000 satellites in 2024 to 12,600 by 2027. Companies in the lasercom ecosystem can take some of the following actions to capitalize on the opportunity:

• Explore the Government and Commercial Sectors: The government and defense sector will have some of the most advanced deployments of laser satellite communication systems, with examples such as PWSA and IRIS2. Third-party terminals are the preferred purchasing option for these networks, making terminal vendors a key partner. The commercial sector may also present opportunities, as networks leveraging lasercom are still evolving and new connectivity platforms, such as HAPS using Optical-Inter-HAPS-Links (OIHL), alongside LEO satellite systems, will stimulate demand.
• Prioritize Scalability and Interoperability for Terminals: The satellite industry is expected to see a sizable increase in users around the world, as users adopt satellite broadband at home and even D2C services directly from their iPhone or Android devices. The user segment is rapidly evolving, and organizations will need to have agile systems that cater to the evolving needs of this segment. This requires that technology solutions in both the space and ground segments be interoperable with various generations of technology, particularly optical terminals. Vendors of optical terminals should prioritize developing scalable and interoperable solutions that allow systems to connect across different generations and technology platforms. This approach will enhance the optimization and cost-effectiveness of laser networks in the long term.
• Embrace Partnership Opportunities: Given the complexity and scale of OISL satellite networks, terminal vendors and network operators should consider fostering partnerships with other industry players. This could include working with network operators, service providers, or even other terminal manufacturers to develop integrated solutions and expand their market reach. Connecting the data center, Artificial Intelligence (AI), and government markets (like connecting NASA, the European Space Agency (ESA), and the China National Space Administration (CNSA) assets) would be a strong strategy for collaboration and expanding revenue streams.
• Enable OISLs with Regenerative Payloads: Enabling OISLs is heavily dependent on regenerative payloads, which handle onboard data processing between laser links. This capability allows data to be routed and retransmitted across multiple hops within the mesh network, reducing dependence on ground stations. Therefore, satellite manufacturers and operators should consider regenerative payloads from layer 1, 2, and 3 perspectives when designing new systems to enter this market.