Low-cost Projectile Detection and Warning System

Reference#: P02243

The current global climate necessitates protection against attacks from anti-aircraft assaults for both military and civilian aircraft. Many of the currently available counter measure systems work by using an Infrared Counter Measure (IRCM) approach however, the deployment of an IRCM system is prohibitively expensive due to the waveband of light used to do the missile detection. Further, due to the method of detection with these imagers, large amounts of clutter and false signals in the band must be accounted for and processed out. This not only adds to the space, weight, and power requirements, it also greatly adds to the cost. Other approaches, such as the use of technology in the visible near infrared (VNIR) spectral regions have struggled to reject the solar and manmade visible background while at the same time sensing the light from the missile or projectile's plume.

Researchers at the Johns Hopkins Applied Physics Laboratory (APL), in cooperation with The Eddy Company, have developed and successfully tested an affordable system that uses technology in the visible near-infrared spectral region for a silicon-based missile warning system that has both cost and performance benefits.

The APL/Eddy sensor system includes a custom optical assembly, a magneto-optical filter (MOF), a camera assembly and a processor assembly. The key enabling technology is a Wide-Eye magneto-optical filter (MOF)

The MOF technology was originally developed as a tool for studying the sun. The Eddy Company had designed and fabricated narrow field of view MOFs for solar physics and other civilian applications. As the result of this collaborative effort, the design of the MOF cell was changed dramatically to enhance filter throughput as well as decrease operating power, which allows operating conditions on typical military and civilian applications. The traditional length of 5" was shrunk down to around 1.5" and is continually being perfected for shorter path lengths. The system can now operate in a wide field of view surveillance mode (100-degrees by 100 degrees) that is needed for applications such as aircraft self-protection. In parallel with this, the filter has been ruggedized to withstand operating conditions on typical military and civilian applications. This miniaturization and ruggedization has not been achieved before and is what allows the use of MOF technology in a new generation of VNIR missile detection system.

The significance of the APL/Eddy approach in conjunction with an IRCM package is the ability to provide missile warning both during the day or night with extremely low false alarm rates using low cost visible sensing technology. This new system will see a cost savings of more than an order of magnitude as compared to typical IRCM systems while maintaining similar performance. Other applications of this technology include warning systems for grand-based or fixed installations, RPG detection, and explosives detonation detection.

Patent Status: U.S. patent(s) 7570426 issued.

Mr. E. Chalfin
Phone: (443) 778-7473

Additional References:

Link to U.S. Patent and Trademark Office