Accession Number:

ADA244340

Title:

ANDVT Rate Conversion Algorithm (from 2400 b/s to 1200 b/s)

Descriptive Note:

Final rept.,

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s):

Report Date:

1991-12-27

Pagination or Media Count:

28.0

Abstract:

The 2400-bs linear predictive coder LPC is currently being widely deployed to support tactical voice communication over narrowband channels. However, lower-data-rate voice encoders are needed for special applications improved performance in high-bit-error conditions and implementation of integrated voicedata systems. In this report, we generated a rate-conversion algorithm to compress voice data rate from 2400 bs to 1200 bs. Rate reduction is effected outside the Advanced Narrowband Digital Voice Terminal ANDVT, requiring no modification to the ANDVT software and hardware. This is a cost-effective way of obtaining 1200 bs voice data ANDVT users for special communication requirements. Speech intelligibility at 1200 bs as measured by the Diagnostic Rhyme Test is 90.4, which is only 1.7 points below that of the 2400 bs LPC. Thus, 1200 bs speech will be acceptable as 2400 bs speech. Author

Subject Categories:

  • Voice Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE