This paper describes a reliable methodology for radar cross section (RCS) measurement of complex small and large targets in the W band. The backscattering behavior of a small car model was measured in an anechoic chamber along with various automotive related targets in a wide gymnasium. Experimental performance in the anechoic chamber is compared to the simulation results. Our simulation model is based on deterministic scattering centers, determined by high frequency approaches, like the physical optics (PO) and the physical theory of diffraction (PTD). Nevertheless, simulations of realistic large objects are both time consuming and difficult to implement. The proposed measurement configuration enables the extraction of non-predetermined scattering points for large object modeling which will significantly decrease the simulation time for road scenarios in radar applications.