Abstract: A planar antenna fitted with a reflector of small shape and small depth. A reflector 21 of planar shape is provided at the rear face of a radiator 20 of planar shape made of a triangular loop element. The side sections 21b on both sides of the reflector 21 are bent towards the radiator 20 and the separation .alpha.2 between the leading edges of the side sections 21b and the side edges of the radiator 20 is thereby reduced. In this way, an excellent electrical characteristic of the planar antenna 2 fitted with a reflector and can be achieved by reducing the separation D2 of the radiator 20 and reflector 21.

Abstract: A planar antenna fitted with a reflector of small shape and small depth. A reflector 21 of planar shape is provided at the rear face of a radiator 20 of planar shape made of a triangular loop element. The side sections 21b on both sides of the reflector 21 are bent towards the radiator 20 and the separation ?2 between the leading edges of the side sections 21b and the side edges of the radiator 20 is thereby reduced. In this way, an excellent electrical characteristic of the planar antenna 2 fitted with a reflector and can be achieved by reducing the separation D2 of the radiator 20 and reflector 21.

Abstract: An apparatus for detecting the position of the center of rotation of a hub of each wheel of a vehicle, the hub having secured thereto a plurality of laterally extending hub bolts. The apparatus comprises a position-correcting member movable toward and away from the hub bolts so as to be capable of coming into engagement with a first one of the hub bolts and to rotate the hub until a second one of the hub bolts adjacent to the one hub bolt comes into engagement with the position-correcting member, thereby to adjust the angular position of the hub bolts to a desired orientation. There is further provided a position detector movable along the correcting member toward the first and second hub bolts in engagement with the correcting member until it comes into engagement with one of these hub bolts, thereby to detect the position of the contacted hub bolt. The position of the center of rotation of the hub is calculated on the basis of the amounts of displacements of the correcting member and the detector.