Patent ID: 8798695

Claim:
A method comprising: transmitting a signal on a first antenna of a user device; measuring the transmitted signal on a second antenna of the user device; computing a magnitude of mutual coupling between the first antenna and the second antenna using the transmitted signal and the measured signal; detecting a presence of an object in proximity to the user device using the magnitude of mutual coupling; and distinguishing whether the detected object is likely to be a human body part that absorbs electromagnetic radiation or a second object type that does not absorb electromagnetic radiation using the magnitude of mutual coupling, wherein the distinguishing comprises: determining that the detected object is the human body part that absorbs electromagnetic radiation when the magnitude of mutual coupling between the first antenna and the second antenna does not exceed a first threshold value; and determining that the detected object is of the second object type that does not absorb electromagnetic radiation when the magnitude of mutual coupling between the first antenna and the second antenna exceeds the first threshold value and does not exceeds a second threshold value, the second threshold value being greater than the first threshold value.