A team of engineers from the Johns Hopkins University Applied Physics Laboratory (APL) has successfully demonstrated a high-bandwidth, free-space optical (FSO) communications system between two moving ships, proving operational utility of FSO technology in the maritime environment.
Juan Juarez, the technical lead for the team developing the technology, said APL is the first organization to successfully operate such a high-capacity optical communications capability – up to 10 gigabits per second – on the move, on board ships at sea, and in challenging near-shore environments.
"We demonstrated bandwidths that were several orders of magnitude higher than all current radio frequency [RF] communications capability on Navy vessels, and at longer ranges than previously demonstrated FSO technology for maritime applications," Juarez said. "This is the equivalent of having up to 2,000 users simultaneously watching high-definition video streams across the optical link."
The first week of testing was ship-to-shore. The team achieved more than 14 hours of link-up time, including during 4- to 6-foot high seas; 1-2 gigabits of error-free data transport at ranges greater than 25 kilometers; voice communications at greater than 35 kilometers; chat messaging out to 45 kilometers, the maximum available line of sight; and repeatable, semiautomatic reacquisitions over the entire line-of-sight range.
APL also led the DARPA Free Space Optical Experimental Network Experiment (FOENEX) to field-test high-bandwidth communications systems, integrating FSO and radio frequency (RF) technology in a mesh airborne network. "As APL proved in Trident Warrior 2017, FSO technology is finally a viable, non-RF communication technology for US Navy platforms," Juarez said.