Cross Polarization in Large-scale Rectangular Waveguide Slot Array Antenna with Parallel Metallic Plates

A part of constructed large-scale waveguide slot array antenna ultilized in Surface Monitor Radar(SMR) is proposed in this thesis, to which slotted rectangular waveguide with parallel metallic plates in this narrow-beam antenna is applied in order to restrain cross-polarization and obtain relative pure linear polarization so that excellent radiation performance is guaranteed. However, it is figured that the size of the parallel metallic plates can affect cross-polarization at centain frequency range we concern visibly, especially in such a large-scale array antenna,and vast slots graved in waveguide produce acceptable linear polarization but lead to severe cross polarization. Some tips to control cross polarization will be raised and datas about simulation and actual measurement will be shown in this article.