Covert motion trajectories for an airborne object in the detection zone of an onboard Doppler radar station

We study the characteristic features of the detection zone for an onboard radar station for an early radar detection system operating in the impulse-Doppler mode. We show that due to these features, there exist covert trajectories such that objects flying along such trajectories are not detected by this onboard radar station. We derive differential equations that define covert trajectories, find various forms of covert trajectories, and study their properties.