Antenna device

An antenna device comprising:

• a casing having a positioning structure;
• a circuit board disposed in the casing;
• and
• an antenna disposed in the casing and comprising a main body portion and a connection portion connected to each other, wherein the connection portion is connected to a surface of the circuit board, the main body portion is extended on a plane defined by a first axial direction and a second axial direction, the first axial direction is perpendicular to the surface, the second axial direction is parallel to the surface, and the main body portion is positioned on the positioning structure and separated from the circuit board,
• wherein the casing comprises an insulating case and a metal case, the circuit board and the antenna are disposed in the insulating case, the metal case is assembled to the insulating case and covers at least part of the circuit board, and the positioning structure is formed on the insulating case,
• wherein the insulating case has a first accommodating space and a second accommodating space adjacent to each other, the first accommodating space accommodates the circuit board, the second accommodating space accommodates the antenna, and the circuit board is completely located outside the second accommodating space.