125kHz/13.56MHz無線射頻身份識別系統之研製
王尹辰 · 2004
Recently RFID system had been adopted widely in many applications, but the key components are still supplied by the international manufactures. Only a few of local companies have this capability to develop the key components of RFID system. In this thesis, we had accomplished two RFID Systems, which may be applied to access control, parking management and interactive toys. 125kHz RFID system is designed by dual band and dual antenna architecture. The reader contain two antennas, one is for transmitting signal for transponder, and the other one is for receiving respond signal from transponder. Transponder is charged by the reader through the air with 250kHz magnetic signal, then transponder will respond ID code by DPSK modulation at 125kHz. Reader will filter, amplify, and demodulate the signal to analyze the responding code. This design can be operated within the distance of 25 cm. And the 13.56MHz RFID system is especially designed for short range and low cost application, using PWM modulation at 13.56MHz, this design can work within the distance 10 cm. The technology involved in this thesis is very wide including antenna, filter, amplifier, and demodulator circuit for reader and transponder. All system from system spec to circuit design and testing use our own design or co-operate with local IC design companies.