Patent ID: 6584203
Filing Date: 2003-06-24
Classification: H04R

Abstract:
A second-order adaptive differential microphone array (ADMA), comprising:(a) a first first-order element configured to convert a received audio signal into a first electrical signal; (b) a second first-order element configured to convert the received audio signal into a second electrical signal; (c) a first delay node configured to delay the first electrical signal from the first first-order element to generate a delayed first electrical signal; (d) a second delay node configured to delay the second electrical signal from the second first-order element to generate a delayed second electrical signal; (e) a first subtraction node configured to generate a forward-facing cardioid signal based on a difference between the first electrical signal and the delayed second electrical signal; (f) a second subtraction node configured to generate a backward-facing cardioid signal based on a difference between the second electrical signal and the delayed first electrical signal; (g) an amplifier configured to amplify the backward-facing cardioid signal by a gain parameter to generate an amplified backward-facing cardioid signal; and (h) a third subtraction node configured to generate a difference signal for the second-order ADMA based on a difference between the forward-facing cardioid signal and the amplified backward-facing cardioid signal.