Accession Number : ADA188573

Title :   Evaluating the Performance of the LPC (Linear Predictive Coding) 2.4 kbps (Kilobits per second) Processor with Bit Errors Using a Sentence Verification Task.

Descriptive Note : Interim rept. Oct 85-Sep 86,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s) : Schmidt-Nielsen, Astrid ; Kallman, Howard J

PDF Url : ADA188573

Report Date : 30 Nov 1987

Pagination or Media Count : 17

Abstract : The comprehension of narrowband digital speech with bit errors was tested by using a sentence verification task. The use of predicates that were either strongly or weakly related to the subjects (e.g., A toad has warts./ A toad has eyes.) varied the difficulty of the verification task. The test conditions included unprocessed and processed speech using a 2.4 kb/s (kilobits per second) linear predictive coding (LPC) voice processing algorithm with random bit error rates of 0%, 2%, and 5%. In general, response accuracy decreased and reaction time increased with LPC processing and with increasing bit error rates. Weakly related true sentences and strongly related false sentences were more difficult than their counterparts. Interactions between sentence type and speech processing conditions are discussed. Keywords: Intelligibility; Voice communications; Speech recognition; Speech transmission.

Descriptors :   *COMPREHENSION, *INTELLIGIBILITY, *SPEECH RECOGNITION, *SPEECH TRANSMISSION, *VOICE COMMUNICATIONS, *WORDS(LANGUAGE), ACCURACY, ALGORITHMS, CODING, DIGITAL SYSTEMS, ERRORS, LINEAR SYSTEMS, NARROWBAND, PREDICTIONS, PROCESSING, RATES, REACTION TIME, RESPONSE, SPEECH

Subject Categories : Voice Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE