Phased Array Laser Predicted Atmospherics Through Intelligent Non-common path Exploitation (PALPATINE)

High Energy Laser (HEL) systems require exquisite beam pointing and stabilizationĀin order to deliver lethal effects on target, commonly on the order of a microradian. Achieving this control traditionally requires many large optics, sensors, alignment lasers, and other large and expensive components. Ultimately this results in traditional beam control systems requiring up to half of the volume of the entire HEL system, making it the largest subsystem by volume.Ā With the invention of high-speed phase modulators, coherently combined laser systems offer the potential for high-speed electronic steering which can replace much of the beam control system. Such systems can currently be categorized into two families. Tiled array systems are coherently combined laser emitters that have a traditional common mode common path beam control system after the emitter. The primary reason for the beam control system under this architecture is to track the target and provide atmospheric turbulence measurements into the phased array emitter. This has been shown to perform quite well but doesnÆt solve any of the SWAP goals of this topic. On the other end of the spectrum are hill climbing phased arrays that optimize the light received back into power in the bucket detectors. This works for simple targets that obey the relationship that more light reflected back equates to a smaller more intense laser spot on the target, such as a ball bearing. However, modern military threats are rarely simple metallic spheres and complex targets such as unmanned aerial vehicles and cruise missiles require careful aimpoint selection such that critical components are targeted. This is a critical flaw in these architectures in that they are incapable of true aimpoint selection and simple maximize the amount of light returned to the power in bucket sensors. EO Solutions (EOS) with our academic partner, Dr. Jeremy Bos, at Michigan Technological University (MTU) will create a true phased array low SWaP Laser Weapon System (LWS) with on-gimbal integration by utilizing a bistatic beam director architecture utilizing many small apertures arranged as a Shack-Hartmann Wavefront Sensor to sense the necessary atmospheric compensation terms to enable exquisite aimpoint selection and maintenance. Through utilization of our ongoing work on a AFRL STTR (FA945123PA034, Topic #AF22D-T003) on predicting atmospheric wavefronts using neural networks we will sense the wavefront in a ring around the laser and predict the corresponding wavefront that the laser will see. This will allow full electronic wavefront correction and beam steering in a low SWAP non-common path beam control system resulting in a true high energy laser panel. Under this architecture the beam control sensing is agnostic to the HEL used enabling for integration into a wide variety of systems, but during the design phase we will plan for a coherently combined phased array as we believe this offers the most performance and SWAP advantages.