Quantum cryptography without optical fibers

Summary form only given. Current limitations on the range of quantum cryptography systems using optical fibers could be eliminated if it were possible to transmit and receive single photons between a ground station and a satellite, and between two satellites, which would allow the operation of a global network for secure communications. We are currently investigating the feasibility of such systems, with the initial goal of demonstrating secure communications between two ground stations in open air during daylight hours.