Stochastic Characterization of Naval Aircraft Electromagnetic Vulnerability - ElectroMagnetic Susceptibility Threshold Analysis Techniques by Estimati

Military aircraft come replete with interconnected electronic systems (e.g., communication, radar, and navigation systems). As the operating frequencies broaden and systems become more complex, their proper functioning is increasingly threatened by electromagnetic interference (EMI) from high-power external sources encountered in their operating environments as well as internal sources. Because experimental testing of these systems’ EMC in their operational environments comes late in the acquisition process, simulation tools are needed to gauge their system-level immunity to EMI as early as possible in the program in order to minimize acquisition cost and timeline. For such tools to be useful, they must be capable of accounting for the complexities encountered with this problem. This includes computing the fields within aircraft cockpits, cabins and equipment bays as well as currents on objects such as avionic systems and their interconnecting cables. Computations must be done over a broad frequency range representative of the operational EM environments and a nearly infinite number of source geometries fields on and within these complex structures. Significant uncertainty arises due to the complexity of both the physical structures and the variability of the electromagnetic sources to the point of rendering computational electromagnetic (CEM) codes an inefficient means of addressing this problem. The geometrical complexity of critical electronic systems and cabling found on military aircraft and other systems has increased to the point where classical methods of analysis and numerical computation no longer give satisfactory results for EM coupling, propagation, compatibility and other issues of practical concern. Moreover, these systems face a broad range of intentional and unintentional EMI sources and threats. This effort is aimed at developing new computational technologies, called EMSTATES, that permit the characterization of EMI phenomena in complex systems while accounting for their stochastic nature and uncertainties in their composition and input-output characteristics. A key component of this tool is its ability to quantify the results in a stochastic sense in order to facilitate weapon system performance risk assessments. This effort focuses on methods to combine reverberation and mode-stir measurement insight with electromagnetic field sampling statistics to the current problem.