Improved RFID tags

The system and method for using an ultrahigh frequency frequency RFID tag together with the substrate used since a metallic base and a liquid are included are offered. Or it consists of the material which has double 素磁気 amplitude permeability briefly and is used by itself -- or a dielectric isolator material and 組合わ -- the RFID isolator used is 介挿 (ed) between a RFID tag and a substrate. As substitution, the dielectric constant in a border plane with a substrate is high, and material which has at least two different dielectric constants is 介挿 (ed) between a RFID tag and a substrate so that low [the dielectric constant in a border plane with a RFID tag]. This material can be a single material which has a dielectric constant slope, or may be a layer in which many are more separate than 2 or it which has a dielectric constant which is different as substitution although each layer is uniform, and is sandwiched together.