Capacitive measurement system with increased robustness against electro-magnetic interference

摘要

A method for capacitive sensing comprises the steps of tagging a transmitting signal by modulating a sub-carrier on said signal using state of the art modulation techniques; demodulating said subcarrier out of useful/received signal to prove validity of said signal.

主权项

1. A method for capacitive sensing, said method comprising the steps of
generating a control signal and supplying said control signal to a transmitter, said control signal causing said transmitter to generate a transmitting signal; detecting a response signal, said response signal being responsive to a transfer behaviour of a transfer channel for said transmitting signal; determining at least one characteristic of said transfer behaviour from said response signal;said method further comprising the further steps of:
tagging said transmitting signal by modulating a sub-carrier signal on said transmitting signal; validating the result of said determining step by demodulating said sub-carrier signal out of said response signal.