Diffraction of Radio Waves for Ad Hoc Network in a Building by an Elliptical Dielectric Column at the End of an Obstacle

We investigate a new method by which radio waves of GHz band, such as the UWB, have enough electric field strength to establish ad hoc network among mobile terminals in a room or in a building even deep in the geometrical shadow. An improvement of 30 dB at 10 GHz and a high electric field strength almost independent of the UWB frequency are reported in this paper with a simple and effective alignment of an elliptical dielectric column at the end of a finite wall which makes the geometrical shadow of radio waves, e.g. an opening to the next room or to the floor in a building. The theoretical calculations were performed by the 2-D FDTD method.