This paper outlines a study into deployment of a parallel processing scheme on an FPGA to meet the needs of high bandwidth processing in adaptive optics wavefront sensing. By exploiting a multi-stage pipeline approach we have significantly reduced the processing time needed to perform the wavefront sensing operation. The paper details the design, implementation, and performance testing results of the proposed FPGA-based wavefront sensing system.

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Stationary high-bandwidth experiments with a portable lasercom (laser communication) system were performed over a wide range of scintillation indices (< 0.1 to 1) at the Department of Energy's Nevada Test Site in the summer of 2003. Active alignment was performed with a quad-cell tracking detector at the transmitter transponder and a conical-scan tracking beam at the receiver transponder. During good scintillation conditions, 2-km 10-Gb/s and 11-km 2.5-Gb/s capabilities were demonstrated at error-free bit-error rates over continuous intervals on the order of half an hour. The experimental transponder configuration, which had 2.5-cm transmit-side and 8-cm receive-side aperture diameters, is described and test results are presented. Modifications to the stationary beacon-tracking transponder system that support a semi-autonomous (aided-pointing), mobile, lasercom capability are discussed.

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Several applications require agile and accurate positioning of a high power laser beam. Agile positioning is generally accomplished via manipulation of some jointed support apparatus such as a robot arm. The size and weight limitations of high power lasers prevent placement of the laser at the final node of the robot arm.Historically, high power laser beams have been guided from the laser to the final node through a fiber optic link or through alignment-sensitive mirror trains. The use of fiber optics constrains the laser wavelength, the laser beam quality, and the degree of motion per arm joint; complex mirror trains may constrain motion also and they require frequent re-alignment.Hughes has developed a continuous, automatic, closed loop, alignment system for robot arm