Active Protection System - Softkill Measures

Softkill Measures

Softkill measures are applied when it is expected that a sensor-based weapon system can be successfully interfered with. The threat sensor can be either an artificial one, e.g., a solid-state infrared detector, or the human sensory system (eye and/or ear).

Softkill measures generally interfere with the signature of the target to be protected. In the following the term signature refers to the electromagnetic signature of an object in either the ultraviolet (wavelength: 0.3-0.4 µm), visual (0.4-0.8 µm), or infrared (0.8 - 14 µm) spectral range as well as cm-radar range (frequency: 2–18 GHz), mmw-radar (35, 94, 144 GHz) and finally sonar range (either 50 Hz - 3 kHz and/or 3– 15 kHz).

One or more of the following actions may be taken to provide softkill:

• Reduction of signature
• Augmentation of signature

Softkill countermeasures can be divided into on-board and expendable countermeasures. Whereas on-board measures are fixed on the platform to be protected, expendable measures are ejected from the platform.

Preemptive action of countermeasures is directed to generally prevent lock-on of a threat sensor to a certain target. It is based on altering the signature of the target by either concealing the platform signature or enhancing the signature of the background, thus minimizing the contrast between the two.

Reactive action of countermeasures is directed toward break-lock of a threat already homing in on a certain target. It is based on the tactics of signature imitation, augmentation, or reduction.