Title :
A Compact and Broadband Microstrip Stacked Patch Antenna With Circular Polarization for 2.45-GHz Mobile RFID Reader
Author :
Tingqiang Wu ; Hua Su ; Liyun Gan ; Huizhu Chen ; Jingyao Huang ; Huaiwu Zhang
Author_Institution :
Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
A compact and broadband microstrip stacked patch antenna with circular polarization (CP) for a mobile 2.45-GHz passive radio frequency identification (RFID) reader is presented. The proposed antenna consists of two stacked patches fed with an S-shaped impedance-matching network (IMN), which is connected by a probe. With the proposed S-shaped IMN feed technique, a good impedance matching and symmetrical broadside radiation patterns could be obtained. The CP operation could be attained simply by the upper parasitic patch rotating 90° sequentially based on the lower patch and truncating corners. Additionally, with four symmetric-L narrow slots on the patches, the compact operation could be obtained. The proposed reader antenna matching is optimized by regulating the sizes of the S-shaped IMN: Sx and Sy. Experimental results show that the reader antenna of size 58 × 58 × 11 mm3 has a 3-dB beamwidth of more than 91°. The peak gain is optimized in the frequency range from 2.31 to 2.56 GHz of larger than 6 dBi, and it achieves 6.32 dBi in the center frequency 2.45 GHz. The voltage standing wave ratio (VSWR) <; 2 impedance bandwidth is larger than 15.1%.
Keywords :
UHF antennas; antenna feeds; antenna radiation patterns; broadband antennas; electromagnetic wave polarisation; impedance matching; microstrip antennas; mobile radio; radiofrequency identification; CP; S-shaped IMN feed technique; S-shaped impedance-matching network; VSWR; broadband microstrip stacked patch antenna; circular polarization; frequency 2.31 GHz to 2.56 GHz; mobile RFID reader; passive radio frequency identification reader; reader antenna matching; symmetric-L narrow slots; symmetrical broadside radiation patterns; truncating corners; voltage standing wave ratio; Broadband; circular polarization (CP); micro strip antenna; radio frequency identification (RFID) reader antenna;
Journal_Title :
Antennas and Wireless Propagation Letters, IEEE
DOI :
10.1109/LAWP.2013.2261651