Guidance of weapon systems relies on sensors to analyze targets signature. Defense weapon systems also need to detect and then identify threats also using sensors. One important class of sensors is millimeter waves radar systems that are very efficient for all weather detection. But such sensors systems are so complex that they need simulation to be tested in a large variety of operational conditions. And the synthetic environment, which means physical target and its background (terrains, buildings, vegetation and other entities) rather than just the target itself, is very import for such sensors system simulation.