Optical fiber connected millimeter-wave radar for FOD detection on runway

Since the Concorde supersonic aircraft accident in 2000, the threat of Foreign Object Debris (FOD) on airport runways has been focused on. The FOD detection system is expected to prevent such the tragedy. In order to keep the airport runways clean and safe, authors are developing radar to detect small metallic objects on the airport runway surface. Millimeter-wave radar is the first candidate for this purpose because of its high detection resolution. However, the radar surveillance range is generally limited due to the high frequency attenuation and the low power devices. This paper proposes a new concept of FOD detection millimeter-wave radar using a Radio over Fiber (RoF) system. The concept overcomes the attenuation problems by connecting a local signal generator and the millimeter-wave radar module with optical fibers. The optical fiber propagation loss is much less than the free space propagation loss of radio frequency (RF), thus the completely new FOD detection system can be composed by applying the RoF system. Measurements of a prototype system, 94 GHz millimeter-wave radar connected by optical fiber, show the possibilities for the new airport application especially in terms of detection sensitivity.