Antenna element and antenna device

An antenna element configured to be fixed on a printed circuit board with a ground conductor, wherein:

• the antenna element and the printed circuit board form an antenna device when the antenna element is fixed on the printed circuit board;
• the antenna element comprises an upper conductor and at least one pair of legs;
• when the upper conductor is viewed along an up-down direction, the upper conductor has an outer periphery whose shape is line-symmetrical with respect to a line passing through a center of the upper conductor;
• when the upper conductor is viewed along the up-down direction, one of the legs of the pair protrudes in a first orientation while a remaining one of the legs of the pair protrudes in a second orientation;
• the first orientation from the center of the upper conductor is opposite to the second orientation from the center of the upper conductor;
• each of the legs of the pair extends downward in the up-down direction;
• the upper conductor is provided with at least one pair of recessed portions;
• the recessed portions of the pair correspond to the legs of the pair in a one-to-one relationship;
• when the upper conductor is viewed along the up-down direction, one of the recessed portions of the pair is recessed in the second orientation while a remaining one of the recessed portions of the pair is recessed in the first orientation;
• each of the recessed portions is juxtaposed with its corresponding leg in a direction intersecting with a first direction which is defined by the first orientation and the second orientation;
• the antenna element comprises two feeding portions;
• and
• when the upper conductor is viewed along the up-down direction, an imaginary line connecting the center of the upper conductor with one of the two feeding portions forms a 90 degree angle with an imaginary line connecting the center of the upper conductor with a remaining one of the two feeding portions.