Frequency-coded chipless RFID tag based on hybrid coding technique

The frequency-coded chipless RFID tag based on spiral resonators has stable performance, but its size is large and its capacity is small. In this paper, we combine the spiral filter structure with defected ground structure, which can control the attenuation effect generated by spiral filter structure. It encodes data according to the differences of attenuation between traps. The tag with six resonators can only produce just 2
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IDs while the tag with six new structures proposed can produce totally 3
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IDs. The simulation results show that tag has obvious frequency characteristic and can be accurately detected by reader. Results prove that this novel structure can effectively improve the information of tag.