The Effects of Background Noise on the Performance of an Automatic Speech Recogniser

Ambient or environmental noise is a major factor that affects the performance of an automatic speech recogniser. Large vocabulary, speaker-dependent, continuous speech recognisers are commercially available. Speech recognisers perform well in a quiet environment, but poorly in a noisy environment. Speaker-dependent speech recognisers require training prior to them being tested, where the level of background noise in both phases affects the performance of the recogniser. This study aims to determine whether the best performance of a speech recogniser occurs when the levels of background noise during the training and test phases are the same, and how the performance is affected when the levels of background noise during the training and test phases are different. The relationship between the performance of the speech recogniser and upgrading the computer speed and amount of memory as well as software version was also investigated.