Lockheed Martin has secured a contract to begin engineering and manufacturing development (EMD) work on the GPS Spatial Temporal Anti-Jam Receiver (GSTAR) system for the F-35 fighter jets.

The initial contract for the EMD work is valued at $25m. GSTAR, a fully digital system, is meant for installation in the F-35 as part of the aircraft’s Block 4 modernisation phase.

The company will replace the Antenna Electronics Unit (AEU) of the F-35 with the GSTAR system.

Integration of GSTAR will deliver next-generation, anti-jam capabilities.

Lockheed Martin Rotary and Mission Systems advanced product solutions vice-president Hamid Salim said: “We are proud to be the supplier of choice for the F-35 upgrade programme and look forward to providing the GSTAR system for years to come.

“This award is a testament to our Lockheed Martin-wide focus on innovation and advanced technology for the F-35 and our warfighters.”

The Lockheed Martin-led team is focused on incorporating improvements to the stealth aircraft in areas such as sensors, engine, data links, mission systems and weapons.

GSTAR provides protection to the F-35 jet against jamming and spoofing. Key components in the system include a radiofrequency (RF) front-end, digital beamformer and receiver.

In June, Lockheed Martin was awarded a $1.8bn contract to continue Block 4 capability upgrades for the F-35.

The contract involves design maturation and development of Block 4 capabilities in support of the Phase 2.3 pre-modernisation of the F-35 for the US and other participants.