An Effective Fast Matching Oriented Slot Antenna Designing Method with RFID Tag Chip

One of the important factors that determine the performance of RFID (radio frequency identification) system is whether the design of the RFID tag antenna is able to achieve an effective matching between the antenna and its chip. The paper studies how the changes of antenna´s geometry parameters affect both real and imaginary part of impedance of slot antenna by using the MOM (Method of Moment) and then presents an effective method, which achieves quick and effective matching through changing the geometry parameters of the bent slot antenna. The paper further validates its method by designing a slot antenna for a set of chips at 915 MHz frequency band through simulation. The test results show that the matching between slot antenna and tag chip has high matching speed, high efficiency and excellent directivity. And the test also proves ´hat the antenna satisfies the RFID application requirements. All these results further validate the reliability of the presented matching method.