Advanced Tactical Cryocoolers for UAV Applications

Cryogenic electronics have the potential to revolutionize digital communications from Unmanned Aerial Vehicles (UAVs), but must operate at cryogenic temperatures. Commercial cryocoolers are large and inefficient and are unable to meet size, weight, and power requirements for UAVs. Our approach and the innovation is a reverse turbo-Brayton cryocooler that provides refrigeration at 4.2 K and rejects heat at 77 K through boil-off of liquid nitrogen. The cryocooler is predicted to reduce size, weight, and input power by at least an order of magnitude as compared to the current state-of-the-art 4.2 K cryocooler. The nitrogen boil-off rate is reasonable, enabling missions of up to nominally 8 hours using a small dewar of liquid nitrogen. Successful completion of this program will dramatically improve digital communications from UAVs. During the Phase I project, we will finalize specifications for the cryocooler; design the cryocooler and cryostat; determine the size, weight, and input power for the overall cryogenic system; and perform a proof-of-concept test on a critical cryocooler component. During Phase II, we will build and test a critical cryocooler component or a complete cryocooler.