Measurement of VSWR and Matched Impedence for Liquid UHF RFID Applications

In this paper, a multiple printed dipole reader antenna is designed for Ultra High Frequency (UHF) near field Radio Frequency IDentification (RFID). The antenna is looped to produce in-phase current which makes its applicable to small size and pure near-field application requirement. It is mainly used for liquid container tagging system. The designed antenna is analyzed in terms of impedence matching. S parameter simulation of multiple printed dipole antenna is simulated for design with impedence and without impedence. Further the antenna gain is also taken into consideration and analyzed. The antenna is designed with Agilent ADS (Advance Design System).