Patent ID: 7492909

Claim:
A method for acoustic transducer calibration in a portable communications device comprising the steps of: providing a source of pseudo random acoustical noise to a characterized external speaker source separate from the portable communications device; directing the pseudo random acoustical noise to an input of an internal microphone used with the portable communications device; adjusting first coefficients in at least one digital signal processor connected to the internal microphone for a desired microphone frequency response based upon the input of pseudo random acoustical noise; discontinuing the source of pseudo random acoustical noise from the external speaker source; applying the source of pseudo random acoustical noise to an internal speaker source in the portable communications device; increasing the amplitude of the pseudo random acoustic noise such that it can be detected by the internal microphone; adjusting second coefficients in the at least one digital signal processor for a desired internal speaker frequency response based upon the input of the pseudo random acoustical noise; returning the portable communications device to an operational mode; and utilizing a filter between the source of pseudo random acoustical noise and the external speaker to compensate for irregularities in the frequency response of the external speaker.