Packing a punch

There's a powerful substance called gallium nitride working inside many new technologies, from smart light bulbs to quick-charging cellphones to the lasers.

Also known as GaN, the semiconductor material boosts power in all kinds of devices. The first missile to harness the power of GaN tech is GEM-T, short for the Guidance Enhanced Missile – Tactical Ballistic Missile, a mainstay of the Patriot™ air and missile defense system. But not all GaN is created equal; Raytheon Technologies spent more than $300 million developing the sophisticated GaN tech for the defense sector.

GEM-T, used against attacking aircraft and tactical ballistic and cruise missiles, now packs a GaN transmitter that never needs to be recertified over the 45-year life of the missile.

“Our GaN is what’s breathing new life into these transmitters,” said Christine Walsh, program manager for an international Patriot program.

Those years — nearly two decades — have been spent pushing the limits of power and efficiency of GaN in the company's Department of Defense-accredited Trusted Foundry, where high performance GaN amplifiers are made.

How it works

Transmitters connect the missile with the ground system, allowing it to control the weapon during flight. The GaN version in GEM-T uses solid state instead of the conventional traveling wave tube design, which requires a supply of parts and recertification to match the life of the missile. The new versions with GaN do not.

The new transmitter has the same form, fit and function as the old one. It’s also tough, doesn’t require additional cooling, and is ready to operate within seconds of powering up. 

The tech is ready for the U.S. Army, according to Jason Rathbone, former missile integrated product team lead for the Patriot product line.

“Today,” he said, “the legacy transmitters on the current GEM-T missiles need to be periodically rebuilt and recertified, so replacing the old one with the new solid-state transmitter is a smart move.”

Production lines are ready

Patriot maker Raytheon, a Raytheon Technologies business, is ramping up production of the GEM-T missile under a number of international contracts. The new transmitter, which was designed to allow future innovations, is well on its way to completing its qualification programs and will be continually tested during future flight tests.

The first live fire flight test consisted of firing one GEM-T missile at a target in a complex environment at the White Sands Missile Range in New Mexico.

“The system tracked the target, processed the engagement, launched the missile, intercepted and killed the target,” said Brian MacDonald, former director of testing for Patriot. 

Radars and missiles are just the beginning, as GaN technology also has the potential to replace any radio frequency application that requires high power and efficiency in a small space. That includes radio data links, active seekers and proximity fuzes.