Terrestrial Radio Frequency Effect Modeling And Simulation Studies

The simulation of RF environment is an important part in radar electronic combat(EC) simulation system, while simulation of RF environment effects is one of its important components. Based on the type of environment, RF environment effects can be divided into three categories: terrain effects, atmosphere effects and weather effects. This dissertation has studied the effects caused by terrain environment on the propagation of RF signal. The effects includes land clutter, multipath and diffraction. The land clutter is useless signals for target detection caused by land terrain. The multipath effect is some kind of interference which is caused by wave reflection on terrain. The diffraction effect is the phenomenon of wave propagation into shadow region.The mechanism of clutter and clutter models have been analysed, with special attention to the modeling method of statistical clutter. Land clutter data from the MIT Lincoln Lab(MIT-LL) has been analysed and classification of land terrain has been introduced. The techniques for the division of ground patch units and the estimation of shadow regions are analysed. The ZMNL method has been studied and used for generating Weibull random sequence. An engineering method for clutter modeling and simulation is suggested. The mechanism of multipath and diffraction effects is explained. Calculations of path-differences in different cases have been analysed. Calculations of propagation factor in interference region, diffraction region and transition region has been studied. Method of determination of transition region is introduced. Realizations of the two models have been studied.The design and realization of RF environment model has been analysed in detail. This model was created for radar electronic combat simulation system on JMASE platform. Designed and realized using OO method, the RF environment was characterized by modularization, simple interface, expandability, and easy substitution of effects models. The clutter model and the multipath-diffraction model above have been realized as sub models of the RF environment model. In the end of this dissertation, some simulation scenario has been designed and the results have been analysed, which validates the effects model created.