Double-frequency dual-purpose remote metal-resistant RFID passive tag

The invention discloses a double-frequency dual-purpose remote metal-resistant RFID passive tag which comprises a dielectric slab, wherein feed network attaching layers different in electrical length are arranged on the front surface and the back surface of the dielectric slab. A tag chip and a tuning capacitor are arranged on the lateral face of the double-frequency dual-purpose metal-resistant tag, and the tag chip is connected with the tuning capacitor through a parallel circuit and connected with a feed network through a serial circuit. The double-frequency dual-purpose remote metal-resistant RFID passive tag has the advantages of being long in read distance, free of interference of metal environment, low in cost, capable of working in American frequency and European frequency and wide in application range.