A novel method to improve gain and tune impedance of RFID tag patch antenna

Abstract

The effect of ground plane's extension of RFID tag patch antenna on its gain and impedance is discussed. The ground plane's extension at radiating slot can effectively improve gain and will visibly change impedance together with that at non-radiating slot. A general variation law of antenna performance with ground extension is proposed. It's convenient and low-cost to get higher gain and desired impedance through proper ground extensions along both directions rather than designing ground plane meaninglessly. This paper takes an existing RFID patch antenna as an example to verify the proposed theory is effective. © 2012 Springer-Verlag.