Wave height measurement using a short-range FMCW radar for unmanned surface craft

This paper describes a radar system designed for deployment on an unmanned surface craft under development in the Autonomous Ocean Systems Laboratory of Memorial University. The radar system includes two sub-systems: one a long-range radar that detects sea-surface objects a few kilometers away, the other a short-range frequency modulated continuous wave radar. This short-range radar not only detects the near obstacles but also senses the sea state to enhance the navigation safety of the unmanned surface craft. The short-range radar provides a useful complement to the blind zone of the long-range radar and largely determines the survival of the unmanned surface craft in oceans. The design of the short-range system and the experimental results obtained from both wave tank and seasurface tests are presented. The results show that the short-range radar are able to estimate the sea-state by measuring wave height.