Patent ID: 7633179

Claim:
A passenger detection apparatus comprising: a plurality of sensors arranged on a seat in a vehicle; a plurality of shield cables corresponding to the sensors, wherein each shield cable has a shield and a core wire, wherein one end of the core wire is connected to the corresponding one of the sensors; a measurement signal output device for outputting a measurement AC signal; a current detection device for detecting a current output from the measurement signal output device; a canceling signal output device for outputting a capacitance canceling AC signal, which has the same phase and the same level as those of the measurement AC signal; a first selection device for selectively applying one of the measurement AC signal and a DC voltage to the other end of each shield cable; and a second selection device for selectively applying one of the capacitance canceling AC signal and a second signal, which has a different waveform from that of the measurement AC signal, to the shield of each shield cable.