BAE Systems has completed the first phase of a DARPA program focused on reducing heat in high-power radio frequency electronics.
BAE Systems has completed the first phase of a DARPA program focused on reducing heat in high-power radio frequency electronics and will continue the work under Phase 2.
The company’s FAST Labs research and development organization is working under DARPA’s Technologies for Heat Removal in Electronics at the Device Scale (THREADS) program, which seeks to address thermal constraints in RF transistors, particularly those made from gallium nitride (GaN).
“We look forward to advancing to Phase 2 of the THREADS program,” said Isaac Wildeson, principal investigator at BAE Systems’ FAST Labs.
“The progress we’ve made during Phase 1 validates our approach to material and process enhancements and brings us closer to unlocking the full potential of RF-based systems for our warfighters.”
BAE Systems received a $12-million THREADS contract in 2024.
Heat on High-Power RF Systems
RF power amplifiers are used in systems including radar, communications equipment, and electronic warfare platforms.
Increasing their output can improve detection, transmission, and engagement ranges, but higher power also generates additional heat that can reduce performance and device life.
DARPA launched THREADS to address that problem at the transistor level. The program focuses on reducing thermal resistance within RF devices and improving the transfer of heat away from high-power transistor areas without degrading RF performance.
Its targets include X-band transistors and power-amplifier test devices with substantially higher power density than current production GaN amplifiers.
GaN has become important for military RF systems because it can provide higher power density than older semiconductor technologies such as gallium arsenide. However, managing the heat generated by high-power GaN devices remains a key engineering challenge.
THREADS Program
DARPA said in June that Phase 1 performers had demonstrated an approximately fivefold increase in RF power density compared with current state-of-the-art devices, corresponding to roughly a doubling of radar range.
Phase 2 will seek to further increase power and improve thermal performance while examining the RF power levels most relevant to future military systems.
BAE Systems’ THREADS work is being conducted at its Microelectronics Center in Nashua, New Hampshire. The company manufactures GaN and gallium arsenide integrated circuits there for defense applications.
The company is conducting the research with Modern Microsystems and researchers from Penn State University, Stanford University, the University of Notre Dame, and the University of Texas at Dallas.
BAE Systems has said improved thermal management could eventually allow RF systems to operate at higher power without requiring larger equipment.
The company previously estimated that resolving the thermal limitations addressed by THREADS could nearly triple the range of some RF-based systems, although the actual operational benefit will depend on the system and how the technology is integrated.
