Anti-Collision of RFID Tags with Blind DS-CDMA Using ICA

We proposed an anti-collision technique for RFID uplink signals that requires only one antenna and one query using DS-CDMA blind inverse spreading technique. In order to avoid interference, the tag generates a random code for each query and spreads the data. In order to decode the signal spread with an unknown code, blind inverse diffusion is performed using independent component analysis. This eliminates the need for multiple queries and does not require complex control between reader and tag. Blind inverse spreading does not require special hardware and the protocol can be extremely simple, making it possible to create reliable and fast tags and readers at lower cost.