FREE SPACE OPTICS FOR LINE-OF-SIGHT & SATELLITE COMMUNICATIONS

The use of lasers in communications as a reliable alternative (or adjunct) to traditional Radio Frequency (RF) communications is highly problematic due to natural attenuative and refractive atmospheric effects on optical laser signals. Variable water droplet characteristics and cloud densities lead to substantial scattering of optical energy and scrambling of the signal encoded in laser filaments. Atmospheric turbulence creates signal fluctuations and wavefront distortions that severely degrade signal coupling efficiency resulting in excessive measured bit error rates which are unsuitable for high-speed communications. Overcoming these natural barriers has been a focus of the USAF, DoD, and US government research for decades in conjunction with commercial telecom and satellite communications companies. Our Free Space Optical (FSO) technology is designed to defeat adverse atmospheric effects including precipitation, particulates, and atmospheric turbulence. This point-to-point technology can be deployed in all desired Beyond Line of Sight (BLOS) configurations for Space-to-Space (S2S), Space-to-Air (S2A), Space-to-Ground (S2G), and Space-to Maritime (S2M)áconnectivity. Our proposed effort seeks to produceáa dual-channel light filament from a single pulse to create donut-shaped intensity profiles with a null at the center. A vortical channel generates a shock wave that displaces particulates and water droplets creating a transparent tunnel for a second channel ľ the information signal - to transit cleanly through clouds, precipitation, particulates, and atmospheric turbulence. The multiple filaments generated by this structured light mimic the core-cladding structure of an optical waveguide, protecting the information signalĺs integrity as it travels through the atmosphere. Our proposed effort seeks to: Assemble and replicate the original FSO proof-of-concept test configuration in a laboratory environment and conduct testing to establish operational performance benchmarks in preparation for outdoor range testing. Identify and characterize any possible environmental hazards and document equipment handling & operations guidelines. Produce two Optical Communications Terminals (OCTs) in a terrestrial Line-of-Site (LOS configuration). Conduct point-to-point communications tests that meet and/or exceed the performance of traditional RF/Microwave-based systems. Conduct Detectability Trials:á Conduct a series of passive and active spectrum monitoring, using both traditional spectrum analysis and IR surveillance/detection systems under various ambient light and weather conditions to determine if on-site conventional RF and infrared security monitoring systems are able to detect and/or intercept the communications signals under test. Conduct weather/environment trials for both equipment durability and system effectiveness under adverse or non-traditional conditions data, and mobility trials. áá