The data are made of nine sets of measurements of four chipless RFID tags. The first two are made of 2600 measurements made at 160 centimeters (distance between the tag and the antenna) without (first) and with (second) initial background subtraction. The third set is made of 5600 measurements made in the range of 50 – 140 centimeters. The next six sets are measurements made to test models trained with the third set. All the measurements are made in the monostatic configuration.