An antenna includes a first helical arm and a second helical arm. The first helical arm is wound clockwise along a longitudinal direction of an axis of the antenna, and the second helical arm is wound counterclockwise along the longitudinal direction of the axis of the antenna. The second helical arm and the first helical arm form at least one intersecting point, a first feeding point is disposed on the first helical arm, a second feeding point is disposed on the second helical arm, the first feeding point and the second feeding point are two points symmetrical relative to the axis of the antenna, and any intersecting point of the at least one intersecting point further forms a third feeding point, where the first feeding point and the second feeding point are connected to a first feeding port, and the third feeding point is connected to a second feeding port.