Abstract: The invention relates to a transponder that is mounted on a tire. The transponder includes at least one transponder chip and a transponder antenna and is embedded in a substrate which is connected to an inner side of the tire with the aid of an element. The aim of the invention is to provide a transponder with the highest possible durability. To achieve this, the connecting element is a material strip which is only fixed to the inner side of the tire in one sub-section.

Abstract: In a method for monitoring tire air pressure of the wheels of an automobile, longitudinal force of the tires-slip test data pairs are measured and recorded for at least one wheel, while the automobile is being driven. A corresponding evaluation unit determines a compensation curve for the recorded longitudinal force of the tires-slip test data pairs, along with an associated offset value based on a zero point in a longitudinal force of the tires-slip performance graph. From the offset value, the respective wheel radius relationship between at least one driven and one non-driven wheel can be calculated, and from this the relative tire pressure of the wheels can be determined.