We analyze the jamming/deception performance of an active decoy against ground tracking radars on dynamic combat scenarios. Based on the movement and the interference flow of an airborne platform, the trajectories of the active decoy is accurately calculated by solving 6-degree of freedom equations of motion. On realistic combat scenarios, numerical simulations are examined to analyze the jamming performance of the decoy for various movements of the platform and RF specifications of the active decoy. Effective jamming/deception area against the ground tracking radars is estimated from the simulation.