Abstract: To address the dual guidance dilemma of physical line-of-sight occlusion and field-of-view (FOV) violation caused by highly maneuvering targets deploying infrared (IR) decoys during the terminal engagement of air-to-air missiles, this paper proposes a multi-physical-constraint circumvention guidance law against dynamic occlusion. First, considering the asymmetric dynamic diffusion characteristics of IR decoys, a refined sector-arc geometric model is established. Combined with the velocity obstacle method, an anti-occlusion control barrier function is constructed to achieve tight circumvention maneuvers with low energy consumption. Second, to resolve the physical conflict between circumvention maneuvering and FOV maintenance, the target's maximum reachable set is introduced to design a three-stage composite guidance architecture, which consists of active biased circumvention, high-gain rapid target reacquisition, and potential-field-enhanced FOV maintenance. Furthermore, the kinematic boundary conditions for successful circumvention and the finite-time convergence proof for target reacquisition are provided. Finally, the performance of the proposed guidance law is verified through nonlinear kinematic simulations and Monte Carlo runs. Simulation results demonstrate that under multi-source complex disturbances and FOV constraints, 100% safe circumvention is achieved, the successful circumvention boundary approaches the theoretical optimum, and the average miss distance converges to the sub-meter level. Moreover, the algorithm exhibits constant-time computational complexity, verifying the sound comprehensive robustness and real-time engineering applicability of the proposed guidance law.

Key words: air-to-air missile, infrared decoy, anti-occlusion guidance, control barrier function, field-of-view constraint, multi-stage guidance