Ultra-wideband antenna performance comparison

For ground penetrating radar applications antennas with bandwidth typically 3-to-1 or greater are required. Many designs can be found in the literature but performance tends to suffer when extending the bandwidth to lower frequencies. Here the nominal frequency range is 0.3-2.3 GHz (154%) and the TEM horn is used as a reference for performance comparisons. Planar antenna designs have many advantages such as low-profile, light-weight, and ease of fabrication and integration. Various planar monopole and a slot-type antennas are compared where the results show that increasing the size can extend the bandwidth to lower frequencies but introduce radiation pattern instability at high frequency. This paper summarizes a numerical investigation using FEKO to provide antenna alternatives for multistatic radar systems. The results serve to guide the selection of broadband antenna elements for ground penetrating radar system developers.