Active Acoustic Jitter Suppression for the Airborne Laser

The Airborne Laser (ABL) system has extremely tight jitter requirements. Acoustic disturbances, such as those caused by the pressure recovery system of the high power laser, are a significant jitter source. At present, plans for acoustic mitigation rely on passive approaches. There is, however, some uncertainty whether these approaches will provide sufficient attenuation. CSA Engineering proposes to develop active acoustic jitter suppression technologies for application to elements of the ABL optical train. The suitability of the numerous acoustic suppression techniques will be assessed. Conceptual designs using the most promising of these suppression techniques will be performed for several ABL components and subassemblies. Structural-acoustic simulations of the optical elements integrated with models of the host aircraft will be used to evaluate performance levels of these acoustic suppression designs. The predicted attenuation levels, and the physical practicality and modularity of the designs will be used in an overall ranking. At least one design will be selected for further evaluation in a hardware demonstration. In the demonstration, a mockup of the optical element will be constructed and tested for acoustically induced jitter. The measured jitter reduction with the acoustic suppression applied will provide an indication of levels of improvement that are realistically achievable.