Patent ID: 8345015

Claim:
A sensor apparatus for determining a spatial position or movement of limbs, the apparatus comprising: a transmitter electrode, a voltage generator for applying an alternating voltage to the transmitter electrode, a first receiver electrode, a second receiver electrode, and a third receiver electrode, and first, second, and third impedance transformers each having a high impedance input each receiving a voltage from the first, second, and third receiver electrode, respectively, a mean value circuit coupled with the outputs of the first, second, and third impedance transformers; a first differential amplifiers for generating a differential value between the output of the first impedance transformer and the output of the mean value circuit; a second differential amplifiers for generating a differential value between the output of the second impedance transformer and the output of the mean value circuit; a third differential amplifiers for generating a differential value between the output of the third impedance transformer and the output of the mean value circuit.