In the beginning, there was narrowband voice, and it sucked. Then we evolved to narrowband on mobile phones, and it sucked more, due to bandwidth compression and the vagaries of RF signal strength. Rolling into Mobile World Congress (MWC) next week, Fraunhofer IIS is pushing the concept –and its codec – of "Full-HD Voice." Will mobile carriers get on board?
Fraunhofer are the people who brought the world MP3 and AAC, with the latter codec/technology serving as a baseline for a variety of products ranging from music playback to AAC-ELD, also known as Full-HD Voice. The live AAC-LLD demonstration at MWC uses two off-the-shelf Samsung Android phones making mobile calls on an LTE network provisioned by another division of Fraunhofer. A company spokesperson said the demos would be conducted at around 64 Kbps – the bandwidth you'd have for a G.711 or G.722 call.
Why is AAC-LLD so much better? It samples and delivers audio – both voice and music – up to the full range of human hearing of 20 kHz. A vanilla PSTN phone call delivers sound in a 3.5 kHz range while the most commonly used HD voice codecs in broadband and mobile, G.722 and AMR-WB, deliver sound in a 7 kHz range. If you play the bandwidth math game, AAC-LLC delivers more than four times the audio bandwidth of a landline PSTN narrowband call and at least twice the audio bandwidth of current HD voice services.
Fraunhofer is pitching AAC-ELD as the perfect solution to roll out on top of LTE, since it delivers music and other audio at "a quality level comparable with HDTV and BluRay" without increasing bitrates in comparison to today's phone services. Any of the current generation of Android phones has more than enough resources plus dual microphones to effectively use AAC-ELD for phone calls. Add in LTE data rates, and VoLTE transforms into FHDVoLTE. Since it's all VoIP, Full-HD is just a drop in codec for the call setup.
Needless to say, www.full-hd-voice.com is the obligatory website with lots of white papers and online audio demos.
The bigger question is if service providers and device makers will go all-in on the concept. Fraunhofer is not offering AAC-ELD for free. There are royalties to be paid. In addition, mobile service providers will want to conduct tests of their own to ensure that AAC-ELD is clearly better than AMR-WB – and we all know that doesn't happen overnight.
On the other side of the coin is product differentiation and the current trend to put in better audio into phones, with higher-end names such as Beats Audio and Monster lining up with manufacturers such as HTC and Nokia. While audio geekdom has preached the virtues of HD voice for years and decades, to date there's been no hot name hook to get consumers on board. I believe it's only a matter of time before someone puts two plus two together and combines the strength of an audio brand name with HD voice to push the better call quality forward.
Edited by
Carrie Schmelkin