RFID tag having antenna with co-planar radiation pattern

摘要

An radio frequency identification (“RFID”) system and RFID tag that include a substrate body having a surface where the substrate body defines a plane of the tag, an RFID integrated circuit disposed on the surface of the substrate body, and an antenna that has an antenna pattern, which is disposed on the substrate body and in electrical communication with the RFID integrated circuit, the antenna generating a radiation pattern with maximum gain along an axis that is substantially coplanar with the tag. The antenna can include a first antenna portion and a second antenna portion, the first antenna portion having a first antenna end and a second antenna end, the first antenna end of the first antenna portion in electrical communication with the RFID integrated circuit and the first antenna portion forming an antenna pattern in a counterclockwise direction, and the second antenna portion having a first antenna end and a second antenna end, the first antenna end of the second antenna portion in electrical communication with the RFID integrated circuit and the second antenna portion forming an antenna pattern in a clockwise direction.

主权项

1. An radio frequency identification (RFID) tag, the tag comprising:
a substrate having a first surface and a second surface opposite to the first surface, the substrate defining a plane of the tag; a conductive element disposed on the first surface of the substrate; an RFID integrated circuit disposed on the second surface of the substrate; and an antenna having an antenna pattern, the antenna disposed on the second surface of the substrate and in electrical communication with the RFID integrated circuit, the antenna having a first clockwise dipole element forming a first spiral and a second counterclockwise dipole element forming a second spiral, the antenna and the conductive element arranged to generate a radiation pattern having a maximum gain along an axis that is substantially coplanar with the plane of the tag that is greater than a maximum gain along an axis that is substantially orthogonal to the plane of the tag, the radiation pattern exhibiting a null substantially orthogonal to the plane of the tag.