Abstract: The present invention is characterized by an antenna device including: a circuit board; a circuit pattern formed by a conductor on a surface of the circuit board; and a minute loop antenna mounted on the circuit board and formed in a loop shape by a conductor having two end portions, wherein the circuit pattern includes at least a feeder circuit configured to supply power to the minute loop antenna, and a ground, and the minute loop antenna is mounted on the circuit board such that: the conductor having the two end portions is connected at one end thereof to the feeder circuit and connected at another end thereof to the ground; a loop surface of the conductor having the two end portions is perpendicular to a plane on which the circuit pattern is formed; and a normal line passing through the loop surface does not pass through the circuit pattern.

Abstract: The present invention is characterized by an antenna device including: a circuit board; a circuit pattern formed by a conductor on a surface of the circuit board; and a minute loop antenna mounted on the circuit board and formed in a loop shape by a conductor having two end portions, wherein the circuit pattern includes at least a feeder circuit configured to supply power to the minute loop antenna, and a ground, and the minute loop antenna is mounted on the circuit board such that: the conductor having the two end portions is connected at one end thereof to the feeder circuit and connected at another end thereof to the ground; a loop surface of the conductor having the two end portions is perpendicular to a plane on which the circuit pattern is formed; and a normal line passing through the loop surface does not pass through the circuit pattern.