Key To Uhf High-speed Passive Electronic Tag And Reader Technology Development

In this thesis, some of the key parts about Tag and Reader of high-speed ultra-high frequency (UHF) passive RFID system are conducted the related researchs. Its pre-technology stocks are CS-1 vehicle identification system working on 2.45GHz which has been successfully developed. To achieve low-power consumption, high data rate low-cost requirements, In the article, The following work in the key-technologies aspect of the system are carried out:1. The development of the tag's transceiver circuit was accomplished, including rectifier circuit and the frequency-multipling modulator circuit. With the aid of the computer-aided design software, the two circuits are carried out a complete modeling and design. And the microwave rectifier rectifies output voltage of 2.19V, also, rectifier's efficiency achieves 27.1%. The frequency-multipling modulator has obtained better swith ratio (SR=17dB) at the expense of input VSWR, and under shorting the input end of Modulation signal, its output power can reach -16.2dBm.2. The development of tag's antenna was carried out. Under satisfying the gain not being smaller than 3dB, the stack structure antenna of tag was developed. Comparing with the ordinary microstrip antenna, the horizontal area of this structure of tag's transceiver antenna are reduced 60.9% and 65.5% respectively.3. The development of the fornt-end of reader's receiver was accomplished. Firstly, the proposal to be used of the reader's reciever is given; and then the downward transmission link from tag to reader is analyzed; lastly, each parts of the reciever's front-end is designed and tested. And to reduce the signal crosstalk between the receiver and transmitor of the reader, the stopband antennuation of the front-end bandpass filter was optimized so that the antennuation at 910MHz is more than 80dB.