Diversity Control Among Multiple Coders: A Simple Approach to Multiple Descriptions

This memo presents a voice communication arrangement in which multiple coder-decoder (codec) pairs are coordinated to provide diversified descriptions of the source signal. This arrangement allows the system to robustly mitigate channel erasures that may occur while providing the best possible quality in the absence of channel impairments. 

Since single descriptive systems have been largely deployed in various networks, it is important that diversity systems can maintain backward interoperability. The proposed diversity control strategies achieve this by slightly modifying the legacy encoder, without the need for modifying the legacy decoder.