Universal Vocoder Using Variable Data Rate Vocoding
Rept. for 1 Oct 2010 - 20 Feb 2013
NAVAL RESEARCH LAB WASHINGTON DC
Pagination or Media Count:
To help achieve universal secure communications interoperability in the Department of Defense DoD, one intermediate goal has been the development of a universal voice encoder vocoder that can seamlessly encode speech at a wide range of variable and fixed data rates to suit a wide range of DoD communication equipment. This report describes the most recent advancements in achieving this goal. Four of the most important areas of improvements presented are 1 Significant improvements were made to the variable data rate VDR vocoder that make it much more robust in less than ideal environments. 2 Error control coding is now extended to all VDR modes. 3 Fixed rate vocoding modes based directly on the VDR encoding method were designed so that transcoding between these options can be done directly and with very little degradation in voice quality. 4 Heavily error protected, fixed rate modes were designed. These modes can be used as fail-safe modes to ensure communicability when channels deteriorate to previously unusable levels.
- Numerical Mathematics
- Computer Programming and Software
- Voice Communications