The third Harris navigation payload has been fully integrated onto GPS 3 Space Vehicle 3, pictured here, and the fourth payload was delivered Oct. 29. Photo: Lockheed Martin.

Harris Corporation delivered the advanced navigation payload for the fourth GPS 3 Space Vehicle (SV04) to Lockheed Martin on Oct. 29. Harris delivered two payloads in 2017 and has committed to delivering four more in 2018.

Harris is under contract with Lockheed Martin for 10 GPS 3 navigation payloads. The first payload is fully integrated on the U.S. Air Force’s first GPS 3 satellite, GPS 3 SV01, which was declared available for launch in September, with an expected launch in 2018.

Lockheed Martin has also fully integrated Harris’ second, third and fourth navigation payloads on GPS 3 SV02, SV03 and SV04. The fifth payload for SV05 is in process of environmental testing.

At the heart of Harris’ navigation payloads is a Mission Data Unit (MDU), featuring a 70-percent digital design that links atomic clocks, radiation-hardened computers and powerful transmitters — enabling signals three times more accurate than those on current GPS satellites, according to the company. These payloads also boost satellite signal power, increase jamming resistance by eight times and help extend the satellite’s lifespan.

In November, Harris announced that it had completed development of a fully digital MDU for the GPS 3 satellites 11 and beyond. The new SV 11+ payload design will provide enhanced capabilities and increased performance for the Air Force.