On the implementation of ASR algorithms for hand-held wireless mobile devices

The paper is concerned with the implementation of automatic speech recognition (ASR) based services on wireless mobile devices. Techniques are investigated for improving the performance of ASR systems in the context of the devices themselves, the environments that they are used in, and the networks they are connected to. A set of ASR tasks and ASR system architectures that are applicable to a wide range of simple mobile devices is presented. A prototype ASR based service is defined and the implementation of the service on a wireless mobile device is described. A database of speech utterances was collected from a population of fifty users interacting with this prototype service in multiple environments. An experimental study was performed where model compensation procedures for improving acoustic robustness and lattice rescoring procedures for reducing task perplexity were evaluated on this speech corpus