GPS military code installs complete at master control sites

The United States Space Force’s Space and Missile Systems Center on July 27 completed the military code (M-code) Early Use (MCEU) hardware and software upgrade to the GPS Operational Control System (OCS).

Completion of the upgrade is a major step toward Operational Acceptance of the long-awaited GPS M-code.

Photo: U.S. Air Force photo/Dennis Rogers

The encrypted M-code signal enhances anti-jamming and anti-spoofing capabilities for the warfighter. M-code signals are currently available on all 22 GPS Block IIR-M, IIF and III space vehicles currently on orbit.

The installs were completed at the Master Control Station at Schriever Air Force Base, Colorado, and Alternate Master Control Stations at Vandenberg Air Force Base, California.

The MCEU upgrade allows the OCS Architecture Evolution Plan to task, upload and monitor M-code within the GPS constellation, as well as support testing and fielding of modernized user equipment.

Operational Acceptance Set for November. MCEU will be in a trial period before Operational Acceptance in November. Once Operational Acceptance is granted, upcoming Military Ground User Equipment (MGUE) will be able to leverage the M-code signal-in-space to provide more secure position, navigation and timing (PNT) to warfighters.

“Working closely with Lockheed Martin and our other mission partners — with the common national goal of providing enhanced PNT signal security and safety always in sharp focus — means we’re able to deliver the right mission capability faster to our warfighters,” said Lt. Col. Steven A. Nielson, program manager of the MCEU project.

MCEU serves as a gap-filler for M-code operations before the entire GPS constellation’s operational transition to the Next Generation Operational Control System Block 1, which is now in development.

A key to enabling M-code is a new software-defined receiver being installed at all six Space Force Monitoring Sites. The M-code Monitor Station Technology Improvement and Capability receiver uses commercial, off-the-shelf hardware to cost-effectively receive and process M-code signals, enabling OCS operators to monitor the signals.