A passive/active dual mode radar concept

This work considers the concept of passive radar in conjunction with an active fallback component. The Active Fallback Component (AFC) could take a number of forms, some of which will be discussed here. The success of any sensor depends on its performance and robustness. To improve robustness in a conflict situation, tactics such as sensor relocation are routinely employed so as to deny the enemy fixed targeting locations. In conflict, it is expedient to assume that fixed broadcast infrastructure would be targeted and destroyed. This would, therefore, render passive radars relying solely on broadcast illuminators of opportunity redundant. In other words, passive radars, assuming they would be deployed, would not be robust against the destruction of broadcast infrastructure, which could occur. This work will propose an active component to be used in conjunction with passive radar which can supplement it under normal conditions, and which can be used as a fallback if primary illumination is unavailable. The active component in essence is an additional means of aiding the survival of the covert sensor infrastructure.