Patent ID: 8878550
Filing Date: 2014-11-04
Classification: B60R,E05F,E05Y,G01V,H03K

Abstract:
1. A sensor device for detecting an object in a detection area near an automotive vehicle comprising: a sensor pad, an impedance variation of the sensor pad being used to detect an object in the detection area; a back focus plate disposed behind the sensor pad relative to the detection area; a first surrounding focus plate arranged around the sensor pad; a signal generator driving the sensor pad and the back and first surrounding focus plates with a first set of signals having a predetermined constant phase, frequency and voltage amplitude; at least a second surrounding focus plate arranged around the first surrounding focus plate, the second surrounding focus plate being driven with a second set of signals, the second set being different from the first set of signals; the impedance of the sensor pad being controlled by a driven rail impedance measuring system which includes an inverter, an oscillator, a power supply rail driver with two DC voltage offset follower amplifier outputs for the power supply rails of the inverter and switches that change the pad function from receiver to transmitter/impedance measurer by turning on and off the oscillator drive to the input of the power supply rail driver of the inverter.