L3Harris’ NSA-Certified Crypto Keeps MUOS Battle-Ready for the Long Haul
In a significant advancement for military communications, L3Harris has completed a major upgrade to the security framework of the Mobile User Objective System (MUOS), the U.S. Department of War’s leading ultra-high frequency satellite network. The recent NSA certification of its enhanced Modem Transmission Security Controller (MTC) ensures that the constellation’s five active satellites, along with two additional planned satellites, remain secure, connected, and combat-ready.
MUOS facilitates secure, narrowband, beyond-line-of-sight communications for a variety of users, from warfighters on the ground to airborne and maritime platforms. Central to this mission is resilience—ensuring the effective transmission of voice, video, and data communications, even in contested environments. The upgraded MTC generates cryptographic bitstreams that power anti-jam modems at MUOS ground stations, thereby protecting command and control links to each satellite currently in orbit.
This upgrade represents more than simple technological refreshment; it is a strategic future-proofing initiative. The newly certified MTC replaces outdated first-generation ground Transmission Security (TRANSEC) devices, addressing obsolescence issues while laying the groundwork for the MUOS Service Life Extension (SLE) program. This initiative will introduce two additional satellites, prolonging the system’s operational lifecycle by an impressive 15 years.
Each MUOS satellite is already equipped with L3Harris-built TRANSEC/Communication Security (COMSEC) units. The company’s stronghold in secure, high-Technology Readiness Level (TRL) programmable crypto platforms ensures both seamless integration and interoperability. The outcome is a robust and modernized MUOS constellation, poised to meet the diverse demands of the next 15 years of military operations.
L3Harris is not only safeguarding MUOS but is also enhancing its resilience, intelligence, and readiness for the future.
Source: L3Harris (2026-06-22)
