应用于感知物联网的方向图可重构超高频RFID标签天线

A Hinge-Type and Radiation-Pattern-Reconfigurable Antenna for Cognitive Internet of Things Application

摘要: 本论文提出了一款新颖的应用于感知物联网(CIOT, Cognitive Internet of Things)的方向图可重构的RFID (Radio Frequency Identification)超高频电子标签天线。该RFID超高频电子标签天线为应用于金属物品的偶极子天线，创新之处在于：1) RFID超高频电子标签天线采用汉字结构；2) 偶极子天线应用“铰链型”可旋转结构，在0˚~90˚范围内调控超高频电子标签天线的偶极子臂的夹角，进而实现电子标签天线的阻抗实部在0~90 ohm范围以及虚部在150~260 ohm范围内可调，方向图在边射(约0˚)和前向端射(约−90˚)范围内调控；3) 在该超高频天线偶极子臂夹角固定为某一特定角度(以60˚为例)的前提下，通过在”铰链型”天线的上层加一层介质和电磁带隙栅格结构(EBG, Electromagnetic Band-Gap)进一步调控方向图的辐射方向(以60˚夹角为例，可进一步调控30˚~40˚)。实际测试结果验证了RFID超高频电子标签天线的可翻转偶极子臂对方向图的调控性，以及EBG结构对方向图辐射方向的可调控性。本文探索了可重构天线在RFID超高频电子标签天线的延伸，尤其提出并验证了可翻转偶极子臂以及EBG对RFID超高频电子标签天线的方向图及方向图辐射方向的可调控性能。

Abstract: A hinge-type RFID (Radio Frequency Identification) chip antenna with reconfigurable radiation pattern is proposed for Cognitive Internet of Things (CIOT). As analyzed using FEM (Finite Element Method) the hinge-type structure enables the dipole antenna to be rotatable and by rotating the angle between the two antenna’s arms from 0˚ to 90˚, its radiation pattern can be reconfigured from 40˚ to −90˚ (assuming the axis vertical to ground is 0˚). Moreover, EBG (Electromagnetic Band-Gap) structure is applied to realize further reconfigurable radiation patterns. Specifically, taking 60˚ degree as an example, by tuning the size of rectangular hole of EBG, its radiation patterns could be tuned ±30˚. The reconfigurable radiation pattern is qualitatively verified by experiment using Tagformance measurement system.