The Technology - AMR-WB
One of the international standards based on the patented technologies of
VoiceAge is the Adaptive Multi-Rate-Wideband (“AMR-WB”) standard for wideband speech.
AMR-WB is a wideband speech coding standard which, among other features, provides
significantly improved speech quality at a wider speech bandwidth when compared to
narrowband speech coding. AMR-WB is codified as an international standard, including as
G.722.2, which was promulgated as a standard speech codec by the ITU Telecommunication
Standardization Sector (“ITU-T”) as the “Wideband coding of speech at around 16 kbit/s using
Adaptive Multi-Rate Wideband (AMR-WB).” G.722.2 AMR-WB is the same codec as the
3GPP AMR-WB speech codec, also known as 3GPP TS 26.190.
Several speech codecs competed to serve as the foundation for AMR-WB before
the standard was officially adopted. The selection process was rigorous and extensive, involving numerous experiments covering all
applications defined for AMR-WB. During the testing, the VoiceAge codec was the only codec
to have no failures in any test condition. The VoiceAge codec was the superior codec with
respect to speech quality, technical considerations, and test results, and was the codec chosen to
be the official AMR-WB standard.
The AMR-WB standardized codec serves a variety of important, growing markets
and applications including, but not limited to, high-definition voice services (“HD Voice”) in
wireless telephony, content for media audio, and mobile voice over internet protocol (“VoIP”).
Indeed, in the mobile phone market, HD Voice is the commercial name for the AMR-WB codec.
HD Voice is a ground-breaking development in mobile phone technology, as it overcomes the
limitations of the 300-3400 Hz voiceband traditionally used in mobile telephony; AMR-WB
extends audio bandwidth to 50-7000 Hz, materially improving intelligibility over the narrowband
codec prevalent in mobile telephony.
There are numerous benefits to the users of HD Voice, including:
• Sound quality is greatly improved;
• It is easier to recognize voices and comprehend accented speech;
• It is easier to distinguish confusing or similar sounds, such as between ‘s’ and ‘f’;
• It is easier to hear faint voices and to understand speakers in environments in which
multiple speakers are speaking at the same time;
• Listening is easier and more life-like, resulting in less “listener fatigue” and reducing
miscommunications and misunderstandings;
• It is easier to understand speakers who use a speakerphone or who are in the presence
of background noise; and
• It is easier to distinguish and differentiate between multiple voices on a single call.