Chip Rfid Tags And Design

As an emerging auto identification technology, RFID (Radio Frequency Identification) has the character of small volume, high capacity, long life, reusability and so on. When combining with internet and communication technology, RFID can realize object tracing and information sharing on a global scale.The cost of transponder is a major bottleneck in the application and development of RFID technology, which can have a wide application only if the cost of transponder reduces. The research and design of chipless RFID tags in ultra high frequency in this paper is based on this background. The cost of chipless tags is generally much lower than that of other tag types due to the absence of the microcontroller and on-board battery source. This paper is organized as follows.1) A novel phase-encoded chipless RFID transponder is presented. The transponder comprises three microstrip patch antennas, which are loaded with open circuited high impedance stubs. The antennas are resonant at nearby frequencies, and when excited with their respective resonant frequency signals, they re-radiate backscattered signals with distinct phase characteristics. This phase information is encoded as hexadecimal bits for the proposed chipless RFID tag.2) A novel chipless RFID system based on planar multi-resonators. It consists of a receiving tag antenna, multi-resonating circuit and a transmitting tag antenna. The reader sends out a multi-frequency interrogation signal and the chipless transponder attenuates particular frequencies which creates a unique spectral signature. It uses spectral signatures to encoded data and hence provide a unique ID for every tagged object.3) A novel chipless RFID system based on multi-resonant dipole antenna. The novel transponder consists of a linearly polarized circular monopole antenna coupled to an orthogonally polarized novel dual multi-resonant dipole antenna. The dual multi-resonant antenna has a gain of over 5 dB for all polarization of the interrogation signal. A 6-bit prototype transponder has been presented and the simulation results verity that the cross polar radar cross section corresponds with the return loss of the multi-resonant antenna.