A Wideband Single-Fed, Circularly-Polarized Patch Antenna With Enhanced Axial Ratio Bandwidth for UHF RFID Reader Applications

A wideband single-fed, circularly-polarized patch antenna with enhanced axial ratio bandwidth for RFID reader application is proposed. The antenna consists of a modified half E-shaped patch, a near-field resonant parasitic (NFRP) patch, and four rotated vertical metallic plates on the ground plane. The metallic plates surrounding the main radiator of the modified half E-shaped patch antenna are fabricated vertically on the ground plane. The operating frequency of the antenna decreases substantially with the vertical metallic plates, which is important for miniaturization of RFID applications. With an elliptical slot and a cut on the modified half E-shaped patch, antenna impedance bandwidth and CP performance both improve. A truncated corner patch as an NFRP element can generate an additional CP radiation mode and further enhances the axial ratio and impedance bandwidth. The measured results show that the antenna has an impedance bandwidth of 14.2% (833–960 MHz), a 3-dB AR bandwidth of 9.0% (846–926 MHz), and an average gain of 7.3 dBic over a 3-dB AR bandwidth. The proposed antenna has a compact size and a low profile ( $0.45\lambda _{0}\times 0.45\lambda _{0}\times 0.074\lambda _{0}$ ).

[1]  K. Chung,et al.  A circularly polarized stacked electromagnetically coupled patch antenna , 2004, IEEE Transactions on Antennas and Propagation.

[2]  K. Chung.  A Wideband Circularly Polarized H-Shaped Patch Antenna , 2010, IEEE Transactions on Antennas and Propagation.

[3]  Jyun-Ming Lin,et al.  A Circularly Polarized Ring-Antenna Fed by a Serially Coupled Square Slot-Ring , 2012, IEEE Transactions on Antennas and Propagation.

[4]  Zhongbao Wang,et al.  Single-Fed Broadband Circularly Polarized Stacked Patch Antenna With Horizontally Meandered Strip for Universal UHF RFID Applications , 2011, IEEE Transactions on Microwave Theory and Techniques.

[5]  Xianming Qing,et al.  Asymmetric-Circular Shaped Slotted Microstrip Antennas for Circular Polarization and RFID Applications , 2010, IEEE Transactions on Antennas and Propagation.

[6]  Chow-Yen-Desmond Sim,et al.  A Slot Loaded Circularly Polarized Patch Antenna for UHF RFID Reader , 2012, IEEE Transactions on Antennas and Propagation.

[7]  Nasimuddin,et al.  Compact Asymmetric-Slit Microstrip Antennas for Circular Polarization , 2011, IEEE Transactions on Antennas and Propagation.

[8]  Dan Wu,et al.  Compact and Wideband Directional Circularly Polarized Distributed Patch Antenna With High Efficiency , 2017, IEEE Access.

[9]  L. Wang,et al.  A New Technique to Design Circularly Polarized Microstrip Antenna by Fractal Defected Ground Structure , 2017, IEEE Transactions on Antennas and Propagation.

[10]  Jyun-Ming Lin,et al.  Circularly Polarized Ring-Patch Antenna , 2012, IEEE Antennas and Wireless Propagation Letters.

[11]  Zhenghe Feng,et al.  Low-profile circularly polarised patch–ring antenna with compact feeding network , 2017 .

[12]  Qiang Liu,et al.  Low-Cost Compact Circularly Polarized Directional Antenna for Universal UHF RFID Handheld Reader Applications , 2015, IEEE Antennas and Wireless Propagation Letters.

[13]  Ikmo Park,et al.  Broadband RFID tag antenna with quasi-isotropic radiation pattern , 2005 .

[14]  Anil Kumar Gautam,et al.  Design of Koch Fractal Circularly Polarized Antenna for Handheld UHF RFID Reader Applications , 2016, IEEE Transactions on Antennas and Propagation.

[15]  Yuanan Liu,et al.  Compact broadband circularly-polarised directional universal GNSS antenna with symmetric radiation pattern and stable near-zenith coverage , 2017 .

[16]  Hosung Choo,et al.  Design of planar RFID tag antenna for metallic objects , 2008 .

[17]  Yahya Rahmat-Samii,et al.  Circularly polarised half E-shaped patch antenna: a compact and fabrication-friendly design , 2016 .

[18]  I. J. Bahl,et al.  Microstrip Antennas , 1980 .

[19]  Rowdra Ghatak,et al.  A novel hexagonal wideband circularly polarized stacked patch microstrip antenna , 2015 .

[20]  Shao Yong Zheng,et al.  Design of Wideband Circularly Polarized Antenna Using Coupled Rotated Vertical Metallic Plates , 2018, IEEE Transactions on Antennas and Propagation.

[21]  Kwok L. Chung,et al.  Broadband artistic antenna array composed of circularly-polarized Wang-shaped patch elements , 2017 .

[22]  K. Wei,et al.  A Broadband Slot Antenna With Unidirectional Circularly Polarized Radiation Patterns , 2017, IEEE Antennas and Wireless Propagation Letters.

[23]  Chow-Yen-Desmond Sim,et al.  A circular patch antenna with parasitic element for UHF RFID applications , 2015 .

[24]  C. Y. D. Sim,et al.  Equilateral triangular patch antenna for UHF RFID applications , 2014 .

[25]  Xianming Qing,et al.  A wideband circularly polarized stacked slotted microstrip patch antenna , 2013, IEEE Antennas and Propagation Magazine.

[26]  D. M. Pozar,et al.  Microstrip antennas , 1995, Proc. IEEE.

[27]  Manos M. Tentzeris,et al.  A Novel Circularly Polarized Antenna With Coin-Shaped Patches and a Ring-Shaped Strip for Worldwide UHF RFID Applications , 2015, IEEE Antennas and Wireless Propagation Letters.

[28]  Hua‐Ming Chen,et al.  Proximity-Fed Circularly Polarized Slotted Patch Antenna for RFID Handheld Reader , 2013, IEEE Transactions on Antennas and Propagation.

[29]  Chow-Yen-Desmond Sim,et al.  Slits Loaded Circularly Polarized Universal UHF RFID Reader Antenna , 2015, IEEE Antennas and Wireless Propagation Letters.

[30]  Yi-Wen Hsu,et al.  Broadband circularly polarized antenna with moon-shaped parasitic element , 2016 .

[31]  Mei Li,et al.  A Bandwidth-Enhanced, Compact, Single-Feed, Low-Profile, Multilayered, Circularly Polarized Patch Antenna , 2017, IEEE Antennas and Wireless Propagation Letters.

[32]  Wei Hong,et al.  A Broadband Circularly Polarized Patch Antenna With Improved Axial Ratio , 2015, IEEE Antennas and Wireless Propagation Letters.

[33]  Xianming Qing,et al.  A Universal UHF RFID Reader Antenna , 2009, IEEE Transactions on Microwave Theory and Techniques.