Date Added: Oct 2012
The 3rd Generation Partnership Project (3GPP) along with European Telecommunication Standard Institute (ETSI) recommended new speech coding scheme, called Adaptive Multi Rate (AMR) in 2000 and 2001. The proposed scheme has two variants: AMR-Narrowband (AMR-NB) and AMR-WB (AMR-WideBand). The speech quality of AMR-WB in GSM systems is remarkably high compared with that of AMR-NB speech codec because it encompasses wider bandwidth of the speech signal, 50-7000 Hz, instead of 200-3400 Hz in AMR-NB. But there are always possibilities for improvement.