zuverlu00e4ssigkeitswertung of decoded signalblu00f6cken on speech recognition in wireless ubertragungkanu00e4len

摘要

A method and apparatus for performing automatic speech recognition (ASR) in a distributed ASR system for use over a wireless channel takes advantage of probabilistic information concerning the likelihood that a given portion of the data has been accurately decoded to a particular value. The probability of error in each feature in a transmitted feature set is employed to improve speech recognition performance under adverse channel conditions. Bit error probabilities for each of the bits which are used to encode a given ASR feature are used to compute the confidence level that the system may have in the decoded value of that feature. Features that have been corrupted with high probability are advantageously either not used or are weighted less in the acoustic distance computation performed by the speech recognizer. This novel approach to decoding of ASR features is referred to herein as "soft feature decoding," and produces dramatic improvements in ASR performance under certain adverse channel conditions. IMAGE