The measured insertion loss for each fiber device under emulated atmospheric conditions with D/r0 between 2 and 30 is presented. a 30 μm core diameter multimode fiber butt-coupled to a 16 multi-element, SNSPD array.a multi-plane light conversion device to split the light from a 30 µm core diameter fiber into 7 separate, 15 μm core diameter few-mode fibers butt-coupled to 7 single-element SNSPDs, and.This paper compares insertion loss of the fiber device for two different architectures: To increase the amount of light that can be delivered to the detectors, NASA Glenn Research Center is considering many different fiber/detector architectures. However, commercial off the shelf superconducting nanowire single photon detectors (SNSPDs) are currently limited in area, which limits the core size of the fibers that can efficiently couple to the detectors. The larger the core, the more modes supported. The number of modes supported by a fiber depends on the size of the core. When using fiber coupled single photon detectors, the efficiency of the transmittance is constrained by the modes supported by the fiber. The acquisition time is measured to be less than 60 seconds, with a probability of acquisition success > 99%.Ī key challenge of photon counting optical communication is delivering light with atmospherically distorted wavefronts from the telescope to detectors efficiently. The prototype was designed such that it has an acquisition fieldof-view of 2 deg and tracking field-of-view of 0.5 deg. Replacing the FPA (that typically performs the acquisition function) enables minimization of SWaP in the laser communication terminal design, which is crucial in CubeSat laser communications. Our design fits within 1U (10 cm x 10 cm x 10 cm) with a 6.4 mm diameter MEMS FSM and 1 mm quad detector. In this paper, we present a patent pending method and reference design that implements both acquisition and tracking functions using a MEMS (Micro-Electro-Mechanical-System) FSM and quad detector. Conventional FSMs (fast steering mirrors) and FPAs (focal plane arrays) are too large to be incorporated into CubeSats, which are inherently constrained by low SWaP (Size, Weight, and Power) limits. To increase the laser beam pointing accuracy, active acquisition and tracking of the beam from the counter terminal should be performed. Current CubeSat Laser Communications relies on spacecraft body pointing with thrusters or reaction wheels, resulting in mediocre laser beam pointing accuracy.
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