Loop antenna having better directivity in low range of angle of elevation

摘要

In a loop antenna including a circuit board, a cylindrical body standing on a surface of the circuit board, and a loop antenna element formed on the cylindrical body along the peripheral surface, a tubular insulator member is placed with some space around the cylindrical body. A conductor ring is formed on the tubular insulator member along the peripheral surface, and is placed on an intermediate position between the surface of the circuit board and the plane formed by the loop antenna element. A conductor wall is placed with some space around the cylindrical body on an intermediate distance between the surface of the circuit board and the plane formed by the loop antenna element into height.