A high resolution FMCW X-band radar sensor for vessel underway replenishment at sea applications

The accurate control of two vessels at sea whilst personnel and materials are transferred from one to the other is emerging as an important application in both military and civilian circles. This paper firstly introduces the `RadaScan´ system, explaining how X-band FMCW radar technology has been combined with the use of transponders for the very accurate measurement of range and bearing to two or more locations. The paper will then describe how these measurements are combined in to a position and heading solution that is then supplied to a `dynamic positioning´ system for vessel maneuvering control. This unique radar sensor combined with the computer control system allows one vessel to track and follow the other vessel at close quarters and in heavy sea states whilst the transfer operations are conducted.