Tajin Md Abu Saleh, Dandekar Kapil R
Electrical and Computer Engineering, Drexel University, Philadelphia, PA 19104, USA.
IEEE Access. 2020;8:187365-187372. doi: 10.1109/access.2020.3031296. Epub 2020 Oct 15.
The growing research interest in passive RFID (Radio Frequency Identification)-based devices and sensors in a diverse group of applications calls for flexibility in reader antenna performance. We propose a low-cost, easy-to-fabricate, and pattern reconfigurable UHF (Ultra High Frequency) RFID reader antenna in the RFID ISM band (902-928 MHz in the US). The antenna offers a 54 MHz bandwidth (890 - 944 MHz) and 8.9 dBi maximum gain. The proposed reconfigurable antenna can radiate four electronically switchable radiation beams in the azimuth plane. The antenna is LHCP (Left Hand Circularly Polarized) with axial ratio (AR) in the ranging from 0.45 dB to 7 dB in the RFID ISM band. Simulation and measurements are presented, and they are in good agreement. The proposed reader array performance is compared against a commercially available reader antenna. The pattern reconfigurable UHF RFID reader antenna not only increases the coverage area for conventional RFID applications but also opens the door to on-body RFID sensor implementation and indoor localization applications.
在各种应用中，对基于无源射频识别（RFID）的设备和传感器的研究兴趣日益浓厚，这就要求读取器天线性能具有灵活性。我们提出了一种低成本、易于制造且图案可重构的超高频（UHF）RFID读取器天线，工作在RFID工业、科学和医疗（ISM）频段（在美国为902 - 928 MHz）。该天线提供54 MHz带宽（890 - 944 MHz）和8.9 dBi的最大增益。所提出的可重构天线能够在方位平面内辐射四个电可切换的辐射波束。该天线为左旋圆极化（LHCP），在RFID ISM频段内轴比（AR）范围为0.45 dB至7 dB。文中给出了仿真和测量结果，二者吻合良好。将所提出的读取器阵列性能与一款商用读取器天线进行了比较。这种图案可重构的UHF RFID读取器天线不仅增加了传统RFID应用的覆盖区域，还为人体上的RFID传感器实现和室内定位应用打开了大门。
