Patent ID: 7978146

Claim:
A coil antenna to be provided in a casing of a portable electronic apparatus, the casing having a plate shape and having a first main surface and a second main surface that faces the first main surface and is substantially parallel to the first main surface, the coil antenna comprising: an RFID substrate; and a plurality of coil units, each of the plurality of coil units including a winding, and each of the plurality of coil units being connected to the RFID substrate; wherein the winding of one of the plurality of coil units and the winding of another of the plurality of coil units are disposed on opposite sides of a virtual center line extending in one of a long-axis direction and a short-axis direction of the main surfaces of the casing; and the windings of the plurality of coil units are connected to one another by a conductor, such that winding directions of the windings of the plurality of coil units are the same.