Electromagnetic Modeling And ISAR Imaging Of Missile

The research is carried out on the shape, space distribution and ballistic trajectory character of the missile with simple fake targets of the Second Artillery in order to do some basic work of targets recognition.Electromagnetic model of ballistic missile and inverse synthetic aperture radar (ISAR) imaging are studied in the thesis. Firstly, the wide-band electromagnetic character of ballistic missile is acquired on model of the equivalent multi-scattering centers. In this section, a method is proposed to calculate the radar cross section (RCS) of three dimentional curve wedge. Secondly, on the analysis of the high velocity influence on range profile, a quick estimating method of multi-LFM parameters is proposed, which can estimate the change of frequency rate caused by high velocity and then correct the influence.ISAR imaging is composed of two main steps: motion compensation and imaging processing. In the following, a new range alignment method based on iterative weighed scattering center is proposed, which can reduces the influence of the reciprocity of scatters to accomplish motion compensation. Next, the effect of targets' maneuvering moving on ISAR imaging is analysed. The traditional range-Doppler (RD) algorithm is no longer suitable to the maneuvering target imaging. In this case, time-frequency analysis must be taken for every range cell to obtain Range-Instantaneous Doppler (RID) imaging. A combined time-frequency methed and a reassigned method are proposed in the thesis to use in RID technique, which not only reduces the interference terms but also keeps good time-frequency concentration.In the end of the thesis, ISAR imaging of multi-targets, taken ballistic missile and fake targets for example, is given to prove the feasibility of recognition of ballistic missile and fake targets.