A remotely interrogated sensor for mechanical quantities is presented which is based on the combination of magneto-elastic and magneto-impedance effects. As a consequence, strain inside the sensor element results in a change of the radar reflectivity. The corresponding measurement system and the strategies of signal processing are discussed in a view of an application as a tire sensor. Using this system, it is currently possible to wirelessly detect strains up to 0,2% with a band width of approximately 2 kHz.