NTIA Technical Report TR 13-493
Intelligibility of the Adaptive Multi-Rate Speech Coder in Emergency-Response Environments
December 2012
David J. Atkinson, Stephen D. Voran, and Andrew A. Catellier
Abstract: This report describes speech intelligibility testing conducted on the Adaptive Multi-Rate (AMR) speech coder in seven different environments simulating emergency response conditions and especially fireground conditions. The intelligibility testing protocol was the Modified Rhyme Test (MRT). Conditions included background noises of various types, as well as a mask associated with a self-contained breathing apparatus. Analog FM radio transmission and Project 25 digital radio transmission were also included in the test as reference points. Test participants were persons employed as first responders in public safety fields. Through statistical analysis of 31,500 MRT trials we are able to draw conclusions on speech intelligibility for AMR speech coding relative to analog and digital radio reference points for each of the seven different operating environments.
Keywords: AMBE; AMR; analog FM; LMR; fireground; MBE; MRT; P25; public safety; SCBA mask; speech coder; speech intelligibility; subjective testing
To request a reprint of this report, contact:
Lilli Segre, Publications Officer
Institute for Telecommunication Sciences
(303) 497-3572
lsegre@its.bldrdoc.gov
|
For technical information concerning this report, contact:
Stephen D. Voran
Institute for Telecommunication Sciences
(303) 497-3839
svoran@its.bldrdoc.gov
|
Disclaimer: Certain commercial equipment, components, and software may be identified in this report to specify adequately the technical aspects of the reported results. In no case does such identification imply recommendation or endorsement by the National Telecommunications and Information Administration, nor does it imply that the equipment or software identified is necessarily the best available for the particular application or uses.
Back to Search Results