Acceleration of Ray-Based Radar Cross Section Predictions Using Monostatic-Bistatic Equivalence

摘要

An approach is presented to simulate the monostatic scattering properties of complex shaped realistic objects in a very efficient way. To achieve this, the calculation of the radar cross section (RCS) in the high frequency regime based on the well known shooting and bouncing rays (SBR) technique is considerably accelerated by the use of the monostatic bistatic equivalence principle. Instead of performing independent simulations for all required aspect angles, the concept is based on the idea of additionally exploiting bistatic information for some neighboring aspect angles. This information is obtained relatively cheaply during the SBR process and it can be favorably exploited under certain conditions, mainly that the bistatic angle is small and the object is sufficiently smooth. In this case, the results of the geometrical ray tracing, which consumes a large part of the computational resources for complex shaped objects is reused multiple times with only low additional computational resources. The basic principles and benefits of the methodology are discussed as well as its limitations and drawbacks. Different generic simulation examples are used to show the general applicability of the method and to examine the degradation of the results depending on the applied bistatic angle. Based on these experiences, a passenger car model is simulated at 10 GHz and a considerable reduction of the computational effort by a factor of 32 is estimated for the complete multiaspect simulation problem.