Radio transponder and method for data transmission between a radio transponder reader and the radio transponder

A radio transponder and method for data transfer between a radio transponder reading device and the radio transponder, wherein a control unit of the radio transponder controls a change in a load impedance via a control signal having a selected switching pulse frequency and a selected switching pulse quantity to produce a response signal, where the control unit codes multiple-valued at least ternary symbols into the control signal, and where symbol values are assigned to respective switching pulse sequences each having a unique combination of switching pulse frequency, switching pulse number and phase shift such that only combinations for which the quotient of switching pulse number and switching pulse frequency lies within a predefined value range are selected.