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NIST Special Database 21. NIST Automatic Link Establishment (ALE) Degraded Tones Per Fed-STD-1045A

Published

Author(s)

Charles L. Wilson

Abstract

This set of 12 audio disks and one CD-ROM produced by the National Telecommunications and InformationAdministration's Institute for Telecommunication Sciences is used to test high frequency (HF) Automatic Link Establishment (ALE) radios. As a follow-up to the ALE Clean Tones CD (NIST Special Database 17), they incorporate signal degradation caused by noise, multipath, and fading using the Watterson channel mode1.With these CDs, users may test HF ALE radio performance under degraded conditions specified in the Federal standard without having to purchase a propagation channel simulator.
Citation
World Wide Web-Internet and Web Information Systems

Keywords

audio tones, modem tones, NIST, radio frequencies, software recognition, sound recognition

Citation

Wilson, C. (2008), NIST Special Database 21. NIST Automatic Link Establishment (ALE) Degraded Tones Per Fed-STD-1045A, World Wide Web-Internet and Web Information Systems (Accessed June 20, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created October 16, 2008