Antenna structure for a near-field communication device

摘要

A near field communication (NFC) communicator includes a housing, an NFC controller and an antenna circuit located in the housing. The antenna circuit enable inductive coupling of a near field electromagnetic signal with another antenna circuit in near field range. The antenna circuit includes an antenna element to generate the electromagnetic signal. The communicator also includes a receiver circuit located in the housing for extracting data from modulation induced in the electromagnetic signal which is caused by the inductive coupling of the near field electromagnetic signal with another antenna circuit, a transmitter circuit to generate the near field, a load modulator to modulate the near field to the reader and an energy harvesting circuit to power the rest of the circuit from the external field. A ferrite sheet is located in the housing such that a gap is maintained between the antenna element and the ferrite sheet.

主权项

1. A near field communication (NFC) communicator, comprising:
a housing: an antenna circuit located in said housing to enable inductive coupling of a near field electromagnetic signal with another antenna circuit in near field range, said antenna circuit including an antenna element to generate the electromagnetic signal; an NFC controller circuit located in the housing for generating the near field electromagnetic signal, extracting data from modulation induced in the electromagnetic signal caused by the inductive coupling of the near field electromagnetic signal with another antenna circuit, and energy harvesting; a shielding arrangement located in the housing and disposed between the antenna element and a receiver circuit such that a gap is maintained between the antenna element and the shielding arrangement, the shielding arrangement including a high magnetic permeability sheet disposed between the antenna element and the receiver circuit; and a nonconductive material located between the antenna element and the high magnetic permeability sheet.