(U) Applications of Miniaturized Atomic Magnetic Sensors in Military Systems

A new generation of miniaturized ultra-high sensitivity atomic magnetometers is being developed and integrated into military systems. These new systems aggregate advances in micro-electromechanical systems, atomic physics, optics, electromagnetics, and data acquisition methodologies for record-level performance in terms of total magnetic field sensitivity while attaining large reductions in size, weight, and power. Very small scale sensors (on the order of a few cubic centimeters) have been demonstrated in both scalar and vector modes and integrated into designs for various defense applications. The focus of our work is on the practical integration of these sensors into operational platforms. There are a number of implications for utilizing these sensors in working environments such that signal-to-noise ratios, detection probabilities, and false alarm mitigation are optimized. The challenges of developing working sensor modules and platforms that operate effectively in the Earth's magnetic field for various military target detection, localization, and characterization missions are significant. We examine the mitigation of platform and environmental noise as well as the development of sensor arrays and associated data acquisition systems. Variations of and enhancements to conventional low frequency magnetometry are investigated through preliminary experimental data in addition to modeling and simulations. In particular, we discuss unique deployment concepts for sensor control, target geolocation, and data processing. Emphasis is placed on prototypes with specific bandwidth sensitivity tailored to a subset of platforms (small unmanned ground, unmanned undersea and unmanned aerial vehicles) and targets of interest. Applications include configurations for undersea and underground threat detection particularly those associated with stationary or mobile explosives and compact metallic targets such as munitions, improvised threat devices, submarines, and other hazardous objects. We show the potential of current and future features of miniaturized magnetic sensors including very high magnetic field sensitivities, bandwidth selectivity, source field control, and array processing.