Telephone speech recognition applications at IRST

This paper presents work performed at IRST on automatic telephone speech recognition. The work focuses on development and installation of some systems that allow delivery of automatic services over the telephone. In particular, both a collect call service, for continuous digit recognition, and a voice dialing by name system is described. Both systems use phone-like units, first trained on wideband databases and then refined on telephone speech material collected at IRST. For each application, a test database was collected in the field, for which the results are given. A comparison between some techniques for increasing the robustness with respect to channel and noise effects is included. Finally, research activities aimed at developing dialogue models are summarized.