A base sheet 12 has a structure that stably couples a particular chip measuring 1 mm or less on paper with an antenna line by only disposing the chip and antenna line in such a manner that the chip and antenna line are close to each other, without electrically bringing the chip and antenna line into contact with each other. The base sheet 12 includes a chip 11 having a spiral coil 13 with at least one turn disposed on a surface of the chip, or inside the chip and near the surface thereof and an antenna line 14 having a conductor part 14A orbiting around the coil 13A of the chip 11 or directly over or directly below the coil 13A so that the conductor part is magnetically coupled with the coil 13A. This base sheet has a structure that stably couples even a chip measuring 1 mm or less on paper or the like with an antenna line by only disposing the chip and antenna line in such a manner that the chip and antenna line are close to each other, without physically bringing the chip and antenna line into contact with each other.