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Variable Rate Multi-Mode Wideband (VMR-WB)
The Variable Rate Multi-Mode Wideband (VMR-WB) codec was standardized by 3GPP2 for cdma2000® wideband telephony and multimedia streaming services and is supported in the CableLabs® PacketCable™ 2.0 specification. Designed by Nokia and VoiceAge, VMR-WB is based on the AMR-WB/G.722.2 codec and includes one mode of operation that is interoperable with it.
Wideband spread spectrum (CDMA) systems use rate sets comprised of 4 bit rates referred to as full-rate (FR), half-rate (HR), quarter-rate (QR), and eighth-rate (ER). CdmaOne and cdma2000 systems support two rate sets, referred to as Rate-Set I and Rate-Set II.
VMR-WB operates in four modes in Rate-Set II and one mode in Rate-Set I. Modes 0 to 3 operate in Rate-Set II. Modes 0, 1, and 2 are specific to CDMA systems (i.e., TIA/EIA/IS-95, cdma2000), with mode 0 providing the highest quality and mode 2 the lowest average data rate (ADR). Mode 3 is interoperable with AMR-WB/G.722.2 at 12.65 kbps and below. Mode 4 is compliant with Rate-Set I, with an ADR slightly lower than mode 2 and equivalent or better quality. Applications include wideband telephony (cdma2000 wireless networks, Wi-Fi, VoIP, satellite telephony, video telephony), conferencing, wideband multimedia services in cdma2000 wireless networks, streaming audio over the internet, audio storage and playback, voicemail and store-and-forward messaging. For licensing IPR, please contact licensing@voiceage.com. Applications
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