New FSO ATP Methods for Compact Space Subsystems

Our current and future Free Space Optical (FSO) designs and performance will be presented; Acquisition, Tracking, and Pointing (ATP) will be a key focus along with the size, weight and power (SWaP) of our existing ground systems and our design targets for space applications. Without gimbals, Rislet prisms, steering mirrors, or off-optical-z-axis sensing, and with only five static non-moving optical elements, we simply move an optical fiber in the focal plane to track the input and output beam angles over the entire wide range pointing field in both azimuth and elevation. Our optical design uses only five statically mounted elements. Fine pointing accuracies are sustained over the entire field without the use of coarse pointing and control systems. The impacts on SWaP are significant, and greatly simplify the packaging and ATP control systems. Our bi-directional ground-links have operated from 1 to 10 Gbps with link distances from 1 to 10 km. The primary ground systems that were delivered had ATP fields of 10 degrees or 30 degrees in both azimuth and elevation. For the 30 degrees system, the pointing resolution is 470 nano-radian, while the 10 degrees system provides 147 nano-radian pointing resolution. We also discuss the performance of our ground links and anticipated performance for various space applications.