Multiple descriptions and path diversity using the AMR-WB speech codec for voice communication over MANETs
Jagadeesh Balam, Jerry D. Gibson · 2006
We compare different source diversity methods for converstional voice communication over multiple routes in a mobile ad-hoc network (MANET). A new multiple description (MD) codec based on the AMR-WB codec, with two balanced side descriptions (6.9 kbps each) is presented. We compare the performance of the MD codec against two other diversity methods, 1) duplicating speech encoded with AMR-WB at 6.6 kbps and 2) duplicating speech encoded with AMR-WB at 12.65 kbps. We show that because of the large packet headers added to each packet by typical MANET protocols, the overhead of sending the simple path diversity methods is not much larger than the overhead for sending MD streams over different paths, and the gain in speech quality we get from duplicating AMR-WB at 12.65 kbps over sending MD codec streams is significant. We compare the speech quality delivered by each of the methods under random and bursty packet loss conditions. The quality of decoded speech is evaluated using WPESQ, a wideband extension to the PESQ algorithm.