Abstract: In a digital channel of a digital wireless communication system including at least one mobile station, at least one base transceiver station in communication with the mobile station, a transcoder configured to provide a signal conversion between vocoder frames and pulse code modulation, and a mobile switching center for interconnecting the digital wireless communication system to a public switched telephone network, a method and apparatus for determining a fault in the digital channel is disclosed. The method includes generating a first set of vocoder input parameters from a speech input signal, and generating a second set of vocoder input parameters from an output signal substantially equivalent to the speech input signal as it is received at a mobile station via the digital channel. The method further includes calculating a metric based on the first and the second set of vocoder input parameters, and subsequently determining a fault in the digital channel using the metric.

Abstract: In a digital channel of a digital wireless communication system including at least one mobile station, at least one base transceiver station in communication with the mobile station, a transcoder configured to provide a signal conversion between vocoder frames and pulse code modulation, and a mobile switching center for interconnecting the digital wireless communication system to a public switched telephone network, a method and apparatus for determining a fault in the digital channel is disclosed. The method includes generating a first set of vocoder input parameters from a speech input signal, and generating a second set of vocoder input parameters from an output signal substantially equivalent to the speech input signal as it is received at a mobile station via the digital channel. The method further includes calculating a metric based on the first and the second set of vocoder input parameters, and subsequently determining a fault in the digital channel using the metric.