Wideband transform product code vector quantization speech coder with short delays

A transform product code vector quantization speech coder has been developed. This coder is very simple, and has very short delay, which is acceptable in communication networks. The product code structure makes the system very easy to implement on a single digital signal processor chip. The coder can provide good communication speech quality in the medium coding rate range from 12 kb/s to 16 kb/s. The coder can tolerate quite high channel noise and is very robust compared with conventional adaptive transform coding systems, and therefore very useful for application in communication network environments