Using a low-noise interferometric fiber optic gyro in a pointing, acquisition, and tracking system

Heritage pointing, acquisition, and tracking (PAT) systems have relied on optical tracking with a cooperative remote terminal to stabilize the line-of-sight of optical communications links. A hybrid approach, using new interferometric fiberoptic gyro (IFOG) technology to sense and correct local angular disturbances, blended with optical tracking, is shown to yield two significant advantages over traditional all-optical tracking: (1) line-of-sight stabilization over a very wide disturbance frequency range, down to extremely low frequencies (<<1 Hz), without the need for any optical signal power or cooperation from the remote terminal, and (2) a significant reduction in signal power required for the optical tracker. This paper will present fundamental performance analyses of a hybrid IFOG/optical tracking system and will derive simple design rules that the system designer can use to architect an optimal hybrid IFOG/optical PAT system. In addition, flow-down benefits that can simplify PAT system hardware will be discussed.