Frequency shifted active target for use in FMCW radar systems

Active target based FMCW radar location systems have niche short range applications which include maritime navigation with the berthing of ships and other vessels and avoiding obstacles such as oil rigs. For these types of systems the target return decays at a greater rate than the background clutter, thus making target detection difficult. In this paper, a technique is explored, based on frequency shifting the radar echo within the target, which serves to translate the position of the of the received target return to a higher frequency where the clutter is greatly reduced. It is shown, by means of a suitable design and simulation, that this approach may readily be used to achieve a much greater operating range in these types of location systems.