Design of Compact Circularly Polarized Antennas for UHF RFID Reader

• Main Authors: CHAO,PO-TANG, 趙柏瑭
• Other Authors: CHEN,HUA-MING
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/u9kdp6

碩士 === 國立高雄應用科技大學 === 光電與通訊工程研究所 === 104 === In this thesis, the study mainly focuses on the design of antennas for UHF RFID reader for local specification (Frequency: 922-928 MHz).There are three antennas in this thesis. The advantage are high gain , low profile and minimization of those three antennas. The first one is high gain antenna using microstrip coupling slot to the upper in Chapter 2. The perturbation component was coupling the high gain performance to the polarization structure. In Chapter 3, the second design antenna with a T-shape slit exciting two resonant modes with 90° phase difference for a good circular-polarization radiation. The result in a broadband characteristics , which is suitable for highly restricted space. A compact circularly polarized patch antenna with Swastika shape is proposed Chapter 4. The two near-degenerated resonant modes for circular polarization are produced by adding two strips of unequal side on the diagonal angles. The advantage of this antenna is matching impedance easily. These antenna in this thesis are designed for ultra high frequency (UHF) radio frequency identification (RFID) reader applications. The discussion of the proposed RFID antennas cover all the details of the measured and EM simulation results.