An antenna system includes an antenna element having two antenna feeds and a shared connection to a ground plane. A first antenna portion has a first resonant frequency length of at least one first wavelength formed from a first feed together with the shared ground connection. A second antenna portion has a second resonant frequency length formed from a second feed together with the shared ground connection. First and second slots are respectively positioned between the shared ground connection and the respective first and second feeds such that the slots create inductances. At least a portion of the ground plane is located directly beneath at least a portion of the first and second slots. The first and second slot inductances together with the ground plane capacitances form one or more filter components to isolate the first and second resonant frequencies in the antenna element.