Two-dimensional loaded wire grid for modelling dielectric objects and its application in the implementation of Luneburg lenses

In this study, the performance of two-dimensional (2D) loaded wire grids for modelling the dielectric objects is investigated. In addition, the loaded wire grid is applied to realise a 2D Luneburg lens. First, the accuracy of the loaded wire grid for 2D problems is validated by calculating the fields scattered by an infinite dielectric cylinder illuminated by a line source, and comparing the results with the analytical solution. The effect of the permittivity of the objects on choosing the grid period and of applying the equal area rule to determine the radius of the wires on the accuracy of the far field radiation is investigated. Based on the results on the accuracy of the loaded wire grid, a 2D Luneburg lens is implemented. The issues such as the losses in the lens, the use of a coarse mesh to reduce the number of the wires, the performance of the lens across a frequency bandwidth, and the control of the side lobe level and back radiation are studied.