| 摘要 |
A method is disclosed for effecting electronic article surveillance with a first high frequency signal and a second lower frequency signal, the second signal having a modulation characteristic therewith. Generally rectangular tag devices are attached to said articles for receipt of such signals and for reradiation thereof. The method involves the fabrication of the tag devices by the steps of: (a) providing first and second circuit elements to be of type exhibiting fixed inductive and capacitive reactances; (b) providing a third circuit element to be of type exhibiting voltage dependent capacitive reactance and forming an electrical series circuit of the first, second and third circuit elements; and (c) configuring the first and second circuit elements with respective geometric diversities, whereby the first circuit element extends longitudinally of the device and is of first transverse dimension, and whereby the second circuit element extends longitudinally of the device at least in part jointly spacedly with the first circuit element and is of second transverse dimension substantially exceeding the first transverse dimension, thus effecting predominant different receipt by the first and second circuit elements of the first and second frequency transmitted signals. |
