LONG-RANGE SURFACE-INSENSITIVE PASSIVE RFID TAG

A passive RFID tag that provides long-range reception, even when mounted on a conductive material or a human body. The antenna of the RFID tag is a loop antenna perpendicular to the mounting surface;it may be formed from a tubular sheet of conductive material to reduce conductive losses. An illustrative rectangular loop 1 inch wide by 0.15 inches high by 0.625 inches deep provides a high effective antenna aperture in a compact RFID tag. Multiple mounting positions may be provided for an RFID chip and for a resonating capacitor. Selection of different mounting positions for these components may allow tuning of impedance and resonant frequency without changing components, providing for simpler and more cost-effective manufacturing. The loop antenna may be formed for example from a stamped metal part with a hollow air core, from a double-sided thick PCB, or from an overlay of conductive ink onto a flexible material. 无源RFID标签，即使安装在导电材料或人体，也能提供远程接收。RFID标签的天线是垂直于安装表面的环形天线；它可以由管状导电材料片构成，以减少导电损耗。1英寸宽、0.15英寸高、0.625英寸深