Prediction of Passive Intermodulation on Mesh Reflector Antenna Using Collaborative Simulation: Multiscale Equivalent Method and Nonlinear Model

We propose a collaborative simulation method for evaluation of passive intermodulation (PIM) on mesh reflector antenna. The electric field on the surface of reflector can be simulated exactly and conveniently by the multiscale equivalent method and finite-element method solver. Meanwhile, the coefficients in the nonlinear model of PIM characteristic on mesh structure are determined from the experimental results on mesh reflector sample, so that the PIM of mesh reflector antenna with the same braided form and working conditions can be calculated using the same nonlinear model. In simulation, the PIM calculations of mesh reflector samples based on the actual woven form and with dimensions of 0.25 × 0.25m2 at C-band and Ku-band have been established, indicating basically consistent to the measured results and validating the effectiveness of this method. Moreover, the PIM prediction of a mesh reflector antenna with the same woven structure is also given. These results show that this method can be utilized to predict PIM level of the mesh reflector antenna under conditions of the precise PIM measurement of mesh reflector sample, also providing reference for designing the low PIM microwave components.