Enhanced Full Rate

Enhanced Full Rate or EFR or GSM-EFR is a speech coding standard that was developed in order to improve the quite poor quality of GSM-Full Rate (FR) codec. Working at 12.2 kbit/s the EFR provides wirelike quality in any noise free and background noise conditions. The EFR 12.2 kbit/s speech coding standard is compatible with the highest AMR mode. Although the Enhanced full rate helps to improve call quality, the codec consumes about 5% more energy and so it is recommended for use only when in a poor reception area.
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