Cooperative interception with double-line-of-sight-measuring

Estimation and guidance scheme is presented, which enables two missiles tracking single target cooperatively. Each missile is equipped with an infra-red sensor and measures the LOS angle only. The two missiles form a measuring baseline relative to the target in space and share measured information with each other, enabling that each identifies the target state based triangulation method. However, the observability of this double line-of- sight measuring relative navigation method is weak if the separation angle between both line-of-sight vectors is small. This paper proposes a guidance law that modulates the line- of-sight angle through a performance index. Using this guidance law, the missile with large initial ling-of-sight angle maximizes this index. Whereas the other one minimizes it. Simulation results show that the proposed estimation and guidance scheme improves the homing accuracy and can yield hit-to-kill performance.