Accession Number:

ADA179849

Title:

Intelligibility of ICAO (International Civil Aviation Organization) Spelling Alphabet Words and Digits Using Severely Degraded Speech Communication Systems. Part 1. Narrowband Digital Speech.

Descriptive Note:

Interim rept. Oct 85-Sep 86,

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s):

Report Date:

1987-03-31

Pagination or Media Count:

24.0

Abstract:

The Diagnostic Rhyme Test DRT is widely used to evaluate digital voice systems. Would-be users often have no reference frame of interpreting DRT scores in terms of performance measures that they can understand, e.g., how many operational words are correctly understood. This research was aimed at providing a better understanding of the effects of very poor quality speech on human communication performance. It is especially important to determine how successful communications are likely to be when the speech quality is severely degraded. This report compares the recognition of ICAO spelling alphabet words ALFA, BRAVO, CHARLIE, etc with DRT scores for the same conditions. Confusions among the spelling alphabet words are also given. Two types of speech degradation were selected for investigation narrowband digital speech the DoD standard linear predictive coding algorithm operating at 2400 bitss with varying bit-error rates and analog jamming. The report will be in two parts. Part 1 covers the narrowband digital speech research, and Part 2 will cover the analog speech research.

Subject Categories:

  • Voice Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE