Abstract: A wireless communication system for use in aircraft includes a wireless headset having at least one ear cup with a housing. A first ultra wideband transceiver is disposed in the ear cup housing. A base station includes a second ultra wideband transceiver. The second ultra wideband transceiver wirelessly communicates with the first ultra wideband transceiver.

Abstract: A method of operating a microphone system includes providing first and second microphones associated with a same human speaker. An analog ambient noise signal is received from the first microphone. An analog speech signal is received from the second microphone. The analog ambient noise signal is converted into a digital ambient noise signal. The analog speech signal is converted into a digital speech signal. Digital noise cancellation is performed on the digital speech signal dependent upon the digital ambient noise signal. The digital noise cancellation is performed by digital circuitry. The noise canceled digital speech signal is inputted into an intercom system. A low power condition of the microphone system and/or a failure of the digital circuitry is sensed. In response to the sensing step, an analog-based intercom signal is inputted into the intercom system. The analog-based intercom signal is dependent on the analog speech signal and substantially independent of the analog ambient noise signal.

Abstract: Systems and methods for adaptive feed-forward noise cancellation. The system includes a plurality of reference microphones, an error microphone, a secondary path module, an adaptation controller, and a canceller filter. A finite impulse response (“FIR”) based plant model is converted to an infinite impulse response (“IIR”) based plant model using balanced model reduction. Due to the inherent instability of the adaptive IIR filter, the Schur-Cohn stability test is applied to the denominator coefficients of the IIR filter transfer function to determine the stability of the noise cancellation system. A secondary path of the noise cancellation system is identified in an on-line manner in the secondary path module. If the energy level of the communication signal (e.g., a music signal) is strong, secondary path identification is performed. The adaptation controller controls the updating of the IIR transfer function based on the stability determination and the secondary path.

Abstract: A method of operating a microphone system includes providing first and second microphones associated with a same human speaker. An analog ambient noise signal is received from the first microphone. An analog speech signal is received from the second microphone. The analog ambient noise signal is converted into a digital ambient noise signal. The analog speech signal is converted into a digital speech signal. Digital noise cancellation is performed on the digital speech signal dependent upon the digital ambient noise signal. The digital noise cancellation is performed by digital circuitry. The noise canceled digital speech signal is inputted into an intercom system. A low power condition of the microphone system and/or a failure of the digital circuitry is sensed. In response to the sensing step, an analog-based intercom signal is inputted into the intercom system. The analog-based intercom signal is dependent on the analog speech signal and substantially independent of the analog ambient noise signal.

Abstract: Systems and methods for adaptive feed-forward noise cancellation. The system includes a plurality of reference microphones, an error microphone, a secondary path module, an adaptation controller, and a canceller filter. A finite impulse response (“FIR”) based plant model is converted to an infinite impulse response (“IIR”) based plant model using balanced model reduction. Due to the inherent instability of the adaptive IIR filter, the Schur-Cohn stability test is applied to the denominator coefficients of the IIR filter transfer function to determine the stability of the noise cancellation system. A secondary path of the noise cancellation system is identified in an on-line manner in the secondary path module. If the energy level of the communication signal (e.g., a music signal) is strong, secondary path identification is performed. The adaptation controller controls the updating of the IIR transfer function based on the stability determination and the secondary path.

Abstract: A wireless communication system for use in aircraft includes a wireless headset having at least one ear cup with a housing. A first ultra wideband transceiver is disposed in the ear cup housing. A base station includes a second ultra wideband transceiver. The second ultra wideband transceiver wirelessly communicates with the first ultra wideband transceiver.