Improved Front-End Analysis in the Army System: Linear Transformations of SRUbank

摘要

Front-end acoustic analysis in early versions of the Airborne ReconnaissanceMission (ARM) continuous speech recognition system was based on the SRUbank filterbank analyser. In its default configuration, this is a conventional, high-resolution filterbank analyser with 27 critical band filters spanning the range 0 to 10 kHz and producing 100 frames per second. This memorandum reports experiments which show that recognition accuracy is improved by applying a suitable dimension-reducing linear transformation to the output of SRUbank. Experiments were conducted using several linear transformations of SRUbank, including 8, 12 and 16 cosine coefficients plus mean channel amplitude plus