A signal processing device is provided that includes a modulation unit that produces an amplitude element as well as a phase element from components that are applied thereto. A correction device is also provided, in which at least one of the components is supplied and is compared with an ideal nominal value. This is used to produce a correction factor, which is multiplied by the component which has been compared with the nominal value. The correction factor determined is used to correct any offset or distortion of the components produced by analog circuits.