Performance Evaluation of High Power Microwave Systems Against UAVs A Probabilistic Antenna Propagation Framework with Sensitivity Analysis

We develop a probabilistic, antenna- and propagation-centric framework to quantify the effectiveness of high-power microwave (HPM) engagements against unmanned aerial vehicles (UAVs). The model couples stochastic UAV kinematics, a beam-steering jitter-to-gain mapping, and atmospheric propagation (free-space spreading with gaseous and rain loss) to obtain closed-form statistics of the received pulse energy. From these, we derive analytically evaluable per-pulse and cumulative neutralization probabilities using log-normal closures and Gaussian–Hermite quadrature, and we provide a dwell-time expression under a standard pulse-independence assumption. Analytical predictions closely match large-scale Monte-Carlo simulations across broad parameter ranges. For a representative commercial threshold $E_{\mathrm{t}\mathrm{h}}={10}^{-2}\mathrm{J}$, the model predicts ${\bar{P}}_{\mathrm{k}\mathrm{i}\mathrm{l}\mathrm{l}}\gtrsim 0.4$ per pulse and $P_{\mathrm{k}\mathrm{i}\mathrm{l}\mathrm{l},\mathrm{t}\mathrm{o}\mathrm{t}}>99\mathrm{\%}$ within about $0.1\mathrm{s}$ at kHz PRF; for hardened platforms with $E_{\mathrm{t}\mathrm{h}}={10}^{-1}\mathrm{J}$, ${\bar{P}}_{\mathrm{k}\mathrm{i}\mathrm{l}\mathrm{l}}<1\mathrm{\%}$ and $P_{\mathrm{k}\mathrm{i}\mathrm{l}\mathrm{l},\mathrm{t}\mathrm{o}\mathrm{t}}<20\mathrm{\%}$ after $1\mathrm{s}$. A closed-form sensitivity (elasticity) analysis shows performance is dominated by slant range ($S_{\bar{R}}\approx -2$), with strong secondary dependence on aperture diameter and transmit power; pointing jitter and atmospheric variability are comparatively less influential in the evaluated regimes. The framework yields fast, accurate, and physics-faithful performance predictions and exposes clear antenna/propagation design levers for HPM system sizing and risk-aware mission planning.