Raytheon says that it is ahead of its U.S. rivals in developing gallium nitride (GaN) technology for active, electronically scanned array (AESA) radars and electronic warfare systems, following a number of performance and manufacturing demonstrations.

“I can’t think of any reason you’d stay with GaAs [gallium arsenide] for any new system,” says Steve Bernstein, GaN program manager in Raytheon Integrated Defense Systems’ Advanced Technology Group. The company is already basing its Next Generation Jammer and Air & Missile Defense Radar programs for the U.S. Navy on GaN.

GaN tolerates higher power densities than GaAs and generates higher radio frequency (RF) output power from the same size module, Bernstein says. It operates at higher voltages and therefore converts DC electrical power to RF energy more efficiently, reducing both power and cooling requirements for equal performance. “It is more affordable at the component and system level,” Bernstein notes.

Recent milestones include Pentagon certification for Raytheon’s production process at Manufacturing Readiness Level 8, which clears the way to making components for low-rate initial production systems. The company says it is the only U.S. contractor to achieve MRL 8 so far.

Under the Defense Advanced Research Projects Agency’s Wide Bandgap Semiconductor program, Raytheon has demonstrated high-efficiency power amplifiers and transmit/receive modules. The company also has tested complete transmit/receive (T/R) integrated multichannel modules (Trimms) that combine T/R modules with power, cooling and thermal management subsystems. In one test, Trimms were assembled into a demonstrator array that ran for 1,000 hr., and in another, a single GaN Trimm was installed in an operational GaAs array and operated successfully.