Efficiency of a 3D Metallic Antenna on top of Finite Ground Plane and Soil

The evaluation of noise coming from the soil to the antenna is of paramount concern in radioastronomy. The noise power can be derived from the antenna efficiency calculated as the ratio of the power radiated in the air to the total power fed at the antenna ports. In this paper, we compute the efficiency of the SKALA2 antenna while accounting for the finite ground plane and the lossy soil. A Method of Moments simulation tool based on inhomogeneous plane waves is used to account for the interactions between the antenna and the ground plane in the vicinity of a semi-infinite homogeneous soil. This tool is used to obtain the antenna efficiency and directivity at zenith across frequency considering different soil permittivities and finite ground plane sizes.