Undersea Laser Communications Field Test at the Naval Undersea Warfare Center (NUWC)

Abstract : MIT Lincoln Laboratory conducted a successful field demonstration of narrow-beam laser communications (lasercom) from March 28-April 1, 2016 in the Narragansett Bay, RI, in collaboration with the Naval Undersea Warfare Center (NUWC) Newport. The demonstration achieved real-time communication through turbid harbor waters utilizing a green (515 nm), low-power commercial laser and commercial detectors. Using a single-photon sensitive commercial photo-multiplier tube (PMT), we demonstrated communication rates between 0.7 and 8.7 megabits per second (Mbps) with a sensitivity of better than 1.5 detected photons per bit. In the second communication demonstration, we used a wideband width commercial avalanche photodiode (APD) to achieve 125 Mbps communication rates. In addition to the communication demonstration, high resolution imaging cameras characterized the laserbeam propagation through the harbor waters, providing valuable data to inform lasercom systems design.The field test was a successful proof of concept demonstration providing key milestones toward a high performance lasercom terminal suitable for a mobile undersea platform.