An antenna structure includes an asymmetric antenna, an antenna feed and a ground plane connected to the asymmetric antenna via the antenna feed. The ground plane includes radials which radiate from the antenna feed. Each of the radials includes: a first conductive element having a first end and a second end, the first end being conductively connected to the antenna feed, a second conductive element conductively unconnected to the first conductive element and to the antenna feed, and a resistor connecting the second end of the first conductive element to the second conductive element.