Tesat Delivers Optical Terminals for Lockheed Martin GPS Optical Crosslink Demo

German space communications firm Tesat-Spacecom has delivered its latest generation of optical communication terminals to Lockheed Martin for a high-profile demonstration involving Global Positioning System (GPS) satellites. The effort is part of a broader push by the U.S. Space Force and industry partners to integrate resilient, high-throughput laser-based crosslinks into future satellite constellations.

Optical Crosslinks Aim to Revolutionize Satellite Communications

Traditional radio frequency (RF) links have long served as the backbone of satellite communications. However, RF channels are increasingly congested and vulnerable to jamming or interception. In contrast, optical inter-satellite links (OISLs)—based on laser communications—offer several key advantages:

• Higher data throughput: Laser links can transmit data at rates exceeding 10 Gbps.
• Reduced latency: Direct point-to-point connections between satellites minimize routing delays.
• Enhanced security: Narrow beamwidths make interception and jamming significantly harder.
• Spectrum independence: Optical links bypass crowded RF spectrum allocations.

The U.S. Department of Defense (DoD), particularly through the Space Development Agency (SDA), has prioritized OISLs in its proliferated low Earth orbit (pLEO) architecture. Now that focus is extending into medium Earth orbit (MEO), where GPS satellites operate.

Tesat’s Terminals: Flight-Proven Hardware with Strategic Relevance

Tesat’s SCOT80 (Small Communication Optical Terminal) is at the core of this delivery. The terminal is designed for small- to medium-sized spacecraft and supports bidirectional laser communication with data rates up to 10 Gbps over distances exceeding 5,000 km in LEO-to-LEO or LEO-to-MEO configurations.

The company has already fielded over 20 such terminals across various missions—including on the European Data Relay System (EDRS), NASA’s Laser Communications Relay Demonstration (LCRD), and multiple commercial constellations such as OneWeb and Telesat Lightspeed.

This latest delivery marks Tesat’s first direct involvement in a U.S.-led demonstration involving GPS-class MEO platforms—a significant milestone as the Pentagon evaluates how best to integrate OISLs into legacy positioning infrastructure.

Lockheed Martin’s Role in GPS Modernization

The demonstration is being led by Lockheed Martin under contract with the U.S. Space Force’s Space Systems Command (SSC). The company builds the current generation of GPS III and GPS IIIF satellites—both of which feature increased anti-jam capabilities, improved accuracy, and greater resilience against kinetic or cyber threats compared to their predecessors.

The integration of optical crosslinks represents a potential leap forward in how these satellites communicate—not only with ground stations but also with each other—enabling faster propagation of ephemeris updates, clock corrections, or even encrypted command-and-control messages across the constellation without relying solely on terrestrial relays.

A Step Toward Interoperable Multi-Orbit Architectures

This demonstration aligns closely with broader DoD goals around multi-orbit interoperability—connecting assets across LEO, MEO, GEO and even cislunar domains using secure mesh networks enabled by OISLs.

The SDA’s Tranche 0 and Tranche 1 Transport Layer satellites already use Tesat-derived terminals under Northrop Grumman and York Space Systems platforms. Extending similar capabilities into MEO via this Lockheed-led demo could pave the way for seamless inter-orbit relay chains that span tactical ISR feeds from LEO drones all the way up to strategic navigation signals from MEO-based GPS nodes.

Operational Implications and Next Steps

If successful, this test could inform future requirements for both military PNT systems and commercial satcom operators seeking hardened alternatives to RF-only architectures. It also reinforces Tesat’s position as one of only a few global providers capable of delivering flight-qualified OISL hardware at scale—a capability increasingly sought after by NATO-aligned space programs looking to reduce reliance on Chinese or Russian suppliers in sensitive domains like secure comms or missile warning networks.

No launch date or specific satellite platform has yet been disclosed by Lockheed Martin or SSC regarding when this demo will occur. However, given that initial deliveries have been completed as of October 2025, an orbital test campaign could plausibly begin within calendar year 2026 depending on integration timelines and launch vehicle availability.

A Competitive Field—but Few Proven Players

Tesat competes primarily with Mynaric (Germany/US), General Atomics Electromagnetic Systems (GA-EMS), CACI-LGS Labs (formerly SA Photonics), BridgeComm Inc., and Airbus’ own internal developments in laser comms hardware. While many firms have demonstrated lab-scale prototypes or short-range air-to-ground links using free-space optics (FSO), far fewer have achieved sustained inter-satellite performance under vacuum conditions at operational ranges above 1,000 km.

This gives Tesat a credibility edge—especially given its extensive heritage on EDRS-C/AlphaSat missions operated by ESA—and positions it well for upcoming DoD procurement cycles focused on resilient space transport layers under Joint All-Domain Command & Control (JADC2) mandates.