uApplication of digital terrain models to landing radar simulationv
*S.Fukuda, T. Sakai, T. Mizuno(JAXA)
A radar for navigation in future Japanese lunar/planetary landing missions is being developed in the Japan Aerospace Exploration Agency (JAXA). The C-band pulse radar provides not only altitude information but also relative velocity against the surface for precise soft landing. In this paper, simulation strategy and results of the landing radar will be shown. The simulation can estimate received power and Doppler frequencies by considering antenna beam patterns, incident angles, platform attitudes, pulse width, span loss, and surface scattering coefficients, so that algorithm selection of the velocity measurement and mode design are facilitated. While surface topographical effects are the most delicate in the simulation, we utilize actual digital terrain models (DTM) of not only experimental sites in Japan but also lunar surfaces: The lunar DTMs are created by stereo vision with a pair of SELENE/Kaguya Terrain Camera images. Consequently, the simulation can give realistic outputs against various types of surfaces.