Patent ID: 9686608
Date: 2017-06-20
CPC Classifications: G01H,H04M,H04R

Claim:
1. An acoustic coupling sensor for a portable electronic device, the acoustic coupling sensor comprising: an acoustic transmitter, an acoustic sensor, a reference signal generator coupled to the acoustic transmitter and configured and arranged to generate a reference signal having a frequency band limited relative to audio signal transmissions by the acoustic transmitter, at least one further acoustic sensor, and a level detector configured with circuitry and coupled to the acoustic sensor, the level detector being configured to combine signals representative of the reference signal as received by the acoustic sensor and the at least one further acoustic sensor and to output a control signal which is indicative of a value or level of acoustic coupling between the acoustic transmitter, the acoustic sensor and the at least one further acoustic sensor, and wherein in operation, the reference signal generator is operable to transmit the reference signal to the acoustic transmitter, the acoustic transmitter is operable to transmit the reference signal along with an audio signal and the acoustic sensor is operable to detect an acoustic level of the transmitted reference signal; and a computer processor configured and arranged to adjust a gain of another audio signal input to the acoustic transmitter responsive to an output control signal being indicative of a change in the reference signal level being greater than a threshold value.