Compact Ultra-Wideband Ground Penetrating Radar Antenna for A Cube Rover

A compact ultra-wideband (UWB) ground penetrating radar (GPR) antenna has been developed for extraterrestrial subsurface sensing from 130 MHz to 2000 MHz. The antenna was designed as a payload of a new cube rover developed by Astrobotic Technology for lunar exploration. The maximum payload dimensions of the rover are 55 cm x 23 cm x 27 cm. This innovative antenna design operates in two modes to cover an extremely wide frequency range from 130 MHz to 2 GHz. At 130 MHz the minimum realized gain is about -2 dBi which quickly increase to 2 dBi by 200 MHz and continues to increase to a maximum gain of 11 dBi at 2 GHz. A wideband microstrip balun circuit design is also presented. Finally, measurements were performed and showed good agreement with simulations.