New techniques for automatic speaker verification using telephone speech

This paper describes new techniques for automatic speaker verification using telephone speech. The operation of the system is based on a set of functions of time obtained from acoustic analysis of a fixed, sentence‐long utterance. These time functions are expanded by orthogonal polynomial representations and compared with stored reference functions. After dynamic time warping, a decision is made to accept or reject an identity claim. Three sets of experimental utterances were used for the evaluation of the system. The first and second sets each comprises 50 utterances by 10 customers each and a single utterance by 40 imposters recorded over a conventional telephone connection. The third set comprises 26 utterances by 21 customers each and a single utterance by 55 imposters recorded over a high quality microphone. The first and third sets were uttered by male speakers, whereas the second set was uttered by female speakers. Reference functions and decision thresholds were updated for each customer. The eval...