Radar Detection Performability under Graceful Degradation

Operational reliability has been introduced recently as a useful metric to describe the performability of a radar's signal processing system. In this paper, the concept of operational reliability is investigated for a typical radar scenario in which a phased array radar on an airborne platform is tasked with detecting a vehicle on the ground. Various background clutter scenarios are modeled in order to study the effects of clutter type on operational reliability and the associated optimal threshold. The effects of radar component degradation on operational reliability are investigated for two different radar system components: the receiver chain low noise amplifier and the phased array antenna. The gain degradation of the low-noise amplifier and element failures in the phased array antenna are modeled and applied to the operational reliability calculations under the various clutter scenarios. By adjusting the detection threshold adaptively, it is seen that the operational reliability can be optimally tuned and maximized even under graceful degradation conditions.