ELECTRONIC ARTICLE SURVEILLANCE TAG DEACTIVATION

摘要

A method and system for producing an electromagnetic field that exhibits a strong near field that is sufficient to deactivate an electronic article surveillance, EAS, tag and a weak far field that is insufficient to deactivate the EAS tag are disclosed. According to one embodiment, two half-wavelength dipoles spaced apart by about a half-wavelength are excited by oppositely phased signals.

主权项

1. A near field antenna, comprising:
a first antenna element having a dimension that is about a half wavelength of an excitation frequency, the excitation frequency carried by a first signal applied to the first antenna element with a first relative phase; and a second antenna element having a dimension that is about a half wavelength of the excitation frequency, the first signal being applied to the second antenna element with a second relative phase of about 180 degrees from the first relative phase, the second antenna element being substantially parallel to the first antenna and being displaced from the first antenna element by about a half wavelength of the excitation frequency.