This paper presents two novel UHF RFID near-field reader antennas with uniform vertical electric field distribution. The two antennas have the following common characteristics. First, the radiating parts of the two antennas are simulated and fabricated by the microstrip lines and work using the leakage wave principle of microstrip lines. Second, the end of microstrip lines match the load to form a traveling wave mode of operation, so the two antennas have broadband characteristics. Third, both antennas are fed in a coaxial manner at the center of the antenna. The simulation and measurement results can show that the proposed three-branch antenna and four-branch antenna achieve good impedance matching in the range of 883–960 MHz and 870–960 MHz, respectively, and achieve uniform distribution of the vertical electric field component in a certain area. The reading areas of the three-branch antenna and the four-branch antenna are 70 mm × 70 mm × 90 mm and 100 mm × 100 mm × 120 mm (length × width × height), respectively. Due to the introduction of the ground plate, the antenna gain is low, which meets the design requirements of near-field antennas.

中文翻译：

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垂直电场分布均匀的新型UHF RFID近场阅读器天线

本文介绍了两种具有均匀垂直电场分布的新型UHF RFID近场阅读器天线。这两个天线具有以下共同特征。首先，用微带线模拟和制造两个天线的辐射部分，并利用微带线的泄漏波原理进行工作。其次，微带线的末端与负载相匹配以形成行波工作模式，因此这两个天线具有宽带特性。第三，两个天线以同轴的方式馈入天线的中心。仿真和测量结果表明，所提出的三分支天线和四分支天线分别在883–960 MHz和870–960 MHz范围内实现了良好的阻抗匹配，并实现了垂直电场分量的均匀分布。某个区域。三分支天线和四分支天线的读取区域分别为70 mm×70 mm×90 mm和100 mm×100 mm×120 mm（长×宽×高）。由于引入了接地板，天线增益很低，可以满足近场天线的设计要求。