An antenna includes a feed element, a ground element, and a slot therebetween. The feed element includes a feed end wall and first and second feed side walls extending from the feed end wall at first and second corners. The ground element includes a ground end wall and first and second ground side walls at first and second corners. The slot includes a first slot portion between the first feed and ground side walls, a second slot portion between the second feed and ground side walls, and a third slot portion between the feed and ground end walls. The third slot portion is continuous between the first slot portion and the second slot portion.