Patent ID: 7336931

Claim:
An electrical device comprising in combination: analog conversion circuitry having an input and an output, the analog conversion circuitry is provided for converting a first input signal within a first frequency range applied to the input to an output signal within a second frequency range different from the first frequency range at the output; a signal adding means for adding at least a portion of the output signal as a second input signal to the first input signal, wherein the analog conversion circuitry is capable of converting the second input signal back to the first frequency range; a characteristic deriving means provided for deriving at least one characteristic of the electrical device from the frequency converted second input signal; and an analog transmit device having a first circuit electrically connected to the input of the analog conversion circuitry and a second circuit electrically connected to the output of the analog conversion circuitry, the first circuit being provided for supplying the first input signal and the second circuit being provided for transmitting the output signal, wherein the characteristic deriving means is formed by characterization block connected to the output of the analog conversion circuitry, the characterization block is provided for supplying signal correction data to the first circuit.