Atom interferometric gravity sensor system

Real-time gravity measurements provide an accurate, high-resolution snapshot of the local gravity signature. Information developed from the gravity signature can be a significant contributor to battle space situational awareness, providing enhanced knowledge of the local operating environment and of the location of each operational participant in that environment. The Strategic Systems Programs (SSP) Navigation Branch (SP24) and Lockheed Martin, Maritime Systems and Sensors (MS2) have extensive experience in the development and use of gravity-measuring instrumentation. As part of the Trident Submarine Improved Accuracy Program, SP24 sponsored Lockheed Martin to develop the first submarine real-time gravity gradient system (circa 1990). This system was designed to correct an inertial navigator for gravity induced error. Following completion of this effort SP24 sponsored Lockheed Martin to develop and demonstrate additional gravity based navigation enhancements. These enhancements are currently referred to as gravity navigation and gravity collision avoidance (circa 2000). In more recent years, SP24 has been sponsoring Lockheed Martin, Stanford University, and AOSense, a Stanford University spin off, to investigate the potential of atomic interferometry to be the technology foundation for the next generation, low cost gravity sensor system. This paper describes Atom Interferometric (AI) theory, AI gravity sensor status, AI gravity system mechanization concepts and gravity based navigation enhancements such as gravity navigation and collision avoidance.