Atmospheric transmission from an instrument measuring scatter at 1550 nm

The Naval Research Laboratory (NRL) has extensively investigated atmospheric effects on maritime lasercomm in both long term research studies and short term system demonstrations. A current effort is underway in the ONR Tactical Line-of-Sight Optical Communications (TALON) program to better characterize atmospheric transmission at 1550 nm in multiple climates to enable prediction of communication link performance. In order to allow long term unmanned measurements in these multiple climates, NRL developed a scattering-based 1550 nm transmission sensor similar in function to commercial visible wavelength visibility monitors. After the system was built and calibrated, it was deployed to a number of sites with various climate types to collect data over a 1-month period for each site. This paper describes the development of the instrument and the software. It also presents some of the collected data.