Abstract: The invention relates to a system having an emitter for emitting a first microwave radiation, a receiver for detecting a second microwave radiation derived from the first microwave radiation and a control system connected to the emitter and the receiver. The first microwave radiation is emitted at a plurality of points in time at different frequencies assigned to the points in time. The correlation of point in time and frequency is random or pseudo-random. Alternatively or additionally, at the point in time, the length of the time period for an emission or reception is random or pseudo-random. The invention further relates to a method for suppressing interference in frequency-modulated radar systems.

Abstract: The invention relates to a transponder circuit comprising a high-quality resonator and a demodulator. After being demodulated, the AM-modulated signal emitted by an emitting and receiving appliance has a frequency corresponding to the resonance frequency of the high-quality resonator, for exciting the high-quality resonator. Said transponder circuit also comprises a rectifier, an energy accumulator and a semiconductor circuit which are connected downstream of the resonator. The input impedance of the high-quality resonator is adapted to the loaded impedance of the semiconductor circuit in such a way that a supply voltage for the semiconductor circuit is obtained in the energy accumulator by means of the impedance transformation. Data and/or measuring values can be retrieved and/or updated in a non-contact manner by radio by means of the transponder circuit.

Abstract: The invention relates to a transponder circuit comprising a high-quality resonator and a demodulator. After being demodulated, the AM-modulated signal emitted by an emitting and receiving appliance has a frequency corresponding to the resonance frequency of the high-quality resonator, for exciting the high-quality resonator. Said transponder circuit also comprises a rectifier, an energy accumulator and a semiconductor circuit which are connected downstream of the resonator. The input impedance of the high-quality resonator is adapted to the loaded impedance of the semiconductor circuit in such a way that a supply voltage for the semiconductor circuit is obtained in the energy accumulator by means of the impedance transformation. Data and/or measuring values can be retrieved and/or updated in a non-contact manner by radio by means of the transponder circuit.