US Navy adds M-Code GPS to shield carrier landings from jamming threats at sea

BAE Systems has secured a $16 million award to modernize GPS guidance aboard U.S. Navy aircraft carriers. Collins Aerospace awarded the contract for an M-Code upgrade to the Navy’s Joint Precision Approach and Landing System (JPALS).

The work will introduce a newer military GPS capability to a system that helps pilots land on carriers with high precision. BAE Systems will supply its DIGAR-500M digital GPS anti-jam receiver for the upgrade.

JPALS must maintain accurate navigation when aircraft approach moving carrier decks. Its guidance system supports recoveries during difficult weather and other challenging operating conditions.

M-Code adds GPS protection

M-Code is an encrypted military GPS signal designed to improve resistance against jamming and spoofing. The upgrade will give JPALS access to that signal while preserving existing capabilities.

BAE Systems already supplies the GPS equipment used by JPALS. Those systems currently rely on Selective Availability Anti-Spoofing Module (SAASM) receivers.

The DIGAR-500M will support both SAASM and M-Code operations. That dual-mode capability allows the Navy to manage aircraft with different GPS configurations during the transition.

Such flexibility matters aboard carriers, where multiple aircraft types can operate from the same deck. The system can support precision approaches without requiring an immediate fleet-wide equipment change.

M-Code also adds another layer of protection to navigation signals that aircraft depend on during carrier recoveries.

Digital beamforming fights jamming

The DIGAR family uses digital beamforming to counter interference targeting GPS receivers. Its architecture can steer up to 24 beams simultaneously. Those beams allow the receiver to manage interference across different directions. That capability can help maintain positioning and navigation when hostile systems attempt to disrupt GPS signals.

GPS interference presents a particular challenge for military aviation. Losing reliable navigation information during a carrier approach could complicate an already demanding flight operation.

BAE Systems developed DIGAR for airborne and maritime platforms requiring protected positioning, navigation and timing. The product line also covers applications involving precision weapons and embedded navigation systems. The Navy’s JPALS upgrade will apply that technology directly to carrier aviation.

Carrier landings need precision

JPALS serves as a precision landing aid for Navy aircraft operating around carriers. It helps guide aircraft toward the correct landing area during recoveries. Carrier landings leave pilots little room for navigation errors. Weather, limited visibility, and electronic interference can further complicate the approach.

M-Code integration aims to strengthen the navigation link under those conditions. It also gives JPALS a path toward modernized GPS architecture as older SAASM equipment remains in service.

Molly O’Brien, BAE Systems’ program manager for Airborne GPS, said the upgrade will reinforce JPALS against evolving threats. Work on BAE Systems’ military GPS products will take place at its Cedar Rapids, Iowa, engineering and manufacturing facility.

The $16 million effort therefore centers on a relatively small receiver upgrade with a significant operational role. The Navy wants its carrier aircraft to retain dependable navigation when the final approach matters most.

Source: https://interestingengineering.com/military/m-code-gps-navy-carrier-landings