US Patent 7827846 Monitoring of wearing surface layer thickness

A method of wear level determination and an associated product. Multiple Radio Frequency IDentification (RFID) tags are distributed within a thickness of a wearing surface layer of a tire. The multiple RFID tags include first RFID tags that have not been worn away, second RFID tags that have been worn away, and a special RFID tag that has not been worn away. A measure of wear of the wearing surface layer of the tire is determined from data received from the first RFID tags and from a table in the special RFID tag. The product includes the wearing surface layer of the tire, the multiple RFID tags, and a mechanism for determining the measure of wear of the wearing surface layer.