Patent ID: 8189429

Claim:
An apparatus comprising: a mobile communications device housing having integrated therein: a downlink channel processor to receive an incoming signal from a far end user; a receiver or earpiece speaker coupled to an output of the downlink channel processor to receive the incoming signal from the far end user and to output a receiver acoustic signal; a first microphone located far from the receiver to pick up voice of a near end user and to output a voice signal of the near end user; an uplink channel processor to send the voice signal of the near end user to the far end user; a second microphone located near the receiver to pick up the receiver acoustic signal and to output an audio signal representing the receiver acoustic signal; and a signal processor configured to measure a frequency response which is a function of (a) the audio signal representing the receiver acoustic signal and (b) the incoming signal from the far end user, the signal processor to analyze the frequency response to detect a proximity of the apparatus to an object.