Enhanced Voice Services (EVS) is a superwideband

speech Speech is a human vocal communication using language. Each language uses Phonetics, phonetic combinations of vowel and consonant sounds that form the sound of its words (that is, all English words sound different from all French words, even if ...

audio coding standard An audio coding format (or sometimes audio compression format) is a content representation format for storage or transmission of digital audio (such as in digital television, digital radio and in audio and video files). Examples of audio coding ...

that was developed for

VoLTE Voice over LTE (VoLTE) is an LTE high-speed wireless communication standard for mobile phones and data terminals, including Internet of things (IoT) devices and wearables. VoLTE has up to three times more voice and data capacity than older 3G U ...

. It offers up to 20 kHz audio bandwidth and has high robustness to delay jitter and packet losses due to its channel aware coding and improved

packet loss Packet loss occurs when one or more packets of data travelling across a computer network fail to reach their destination. Packet loss is either caused by errors in data transmission, typically across wireless networks, or network congestion.Kur ...

concealment. It has been developed in 3GPP and is described i
3GPP TS 26.441
The application areas of EVS consist of improved telephony and teleconferencing, audiovisual conferencing services, and streaming audio. Source code of both decoder and encoder in ANSI C is available a
3GPP TS 26.442
and is being updated regularly. Samsung uses the term HD+ when doing a call using EVS.

History

Work on EVS was started in 2007. The standardization process lasted from 2010 to 2014, being completed in December 2014 with 3GPP Release 12.The 3GPP Enhanced Voice Services (EVS) codec.
Nokia white paper. The codec was developed collaboratively among chipset, handset and infrastructure manufacturers as well as operators and technology providers.Enhanced Voice Services (EVS) Codec
Fraunhofer Technical Paper, 2015 GSMA requires EVS for their HD Voice+ Logo Licensing Program. The six patent holders are Fraunhofer IIS,

JVC Kenwood , stylized as JVCKENWOOD, is a Japanese multinational electronics company headquartered in Yokohama, Japan. It was formed from the merger of Victor Company of Japan, Ltd (JVC) and Kenwood Corporation on October 1, 2008. Upon creation, Haruo Kaw ...

, Nippon Telegraph and Telephone, NTT Docomo, Panasonic, and

Ericsson (lit. "Telephone Stock Company of LM Ericsson"), commonly known as Ericsson, is a Swedish multinational networking and telecommunications company headquartered in Stockholm. The company sells infrastructure, software, and services in informat ...

. Other contributors included

Huawei Huawei Technologies Co., Ltd. ( ; ) is a Chinese multinational technology corporation headquartered in Shenzhen, Guangdong, China. It designs, develops, produces and sells telecommunications equipment, consumer electronics and various smar ...

Nokia Nokia Corporation (natively Nokia Oyj, referred to as Nokia) is a Finnish multinational corporation, multinational telecommunications industry, telecommunications, technology company, information technology, and consumer electronics corporatio ...

, Orange,

Qualcomm Qualcomm () is an American multinational corporation headquartered in San Diego, California, and incorporated in Delaware. It creates semiconductors, software, and services related to wireless technology. It owns patents critical to the 5G, 4 ...

Samsung Electronics Samsung Electronics Co., Ltd. (, sometimes shortened to SEC and stylized as SΛMSUNG) is a South Korean multinational corporation, multinational electronics corporation headquartered in Yeongtong-gu, Suwon, South Korea. It is the pinnacle of ...

, VoiceAge, and ZTE Corporation. A patent pool for EVS has been listed by

MPEG LA MPEG LA is an American company based in Denver, Colorado that licenses patent pools covering essential patents required for use of the MPEG-2, MPEG-4, IEEE 1394, VC-1, ATSC, MVC, MPEG-2 Systems, AVC/H.264 and HEVC standards. History MPEG LA ...

Technology

EVS employs similar concepts to its predecessors, such as AMR-WB, to which it retains backward-compatibility. It switches between speech and audio compression modes depending on the content, using ACELP and MDCT. The following features are present in EVS: * source-controlled variable bit-rate (SC-VBR) * voice/sound activity detector (VAD) * comfort noise generation (CNG) *

error concealment Error concealment is a technique used in signal processing that aims to minimize the deterioration of signals caused by missing data, called packet loss. A signal is a message sent from a transmitter to a receiver in multiple small packets. Packet ...

(EC) for packet loss in networks * channel-aware mode to improve frame/packet error resilience * jitter buffer management (JBM) Input sampling rates for EVS can be 8, 16, 32, and 48 kHz. It supports the following bitrates (in kbps) for different bandwidths: * Narrowband (NB): 5.9, 7.2, 8, 9.6, 13.2, 16.4, 24.4 * Wideband (WB): 5.9, 7.2, 8, 9.6, 13.2, 13.2 channel-aware, 16.4, 24.4, 32, 48, 64, 96, 128 (6.6 ~ 23.85 for AMR-WB IO) * Super-wideband (SWB): 9.6, 13.2, 13.2 channel-aware, 16.4, 24.4, 32, 48, 64, 96, 128 * Fullband (FB): 16.4, 24.4, 32, 48, 64, 96, 128 Bitrates can be switched every 20 ms. Subjective listening tests conducted by Nokia concluded that EVS offers significantly improved quality over AMR and AMR-WB at all operating points.

Adoption

Operators which have launched EVS powered

services include: * NTT DoCoMo *

T-Mobile USA T-Mobile US, Inc. is an American wireless network operator headquartered in Overland Park, Kansas and Bellevue, Washington, U.S. Its largest shareholder is a multinational telecommunications company Deutsche Telekom AG, which , holds 48.4 perc ...

T-Mobile Polska T-Mobile Polska S.A. is a Polish mobile phone network operator. The company was formerly named Polska Telefonia Cyfrowa (''lit.'' "Polish Digital Telephony") and operated under the name Era, until being rebranded as T-Mobile on 5 June 2011. As in ...

Vodafone Germany Vodafone GmbH is a mobile telecommunications operator in Germany headquartered in Düsseldorf. It provides mobile phone, LTE, 5G, cable internet, landlines, cable TV, and IPTV services. As of the third quarter of 2021, Vodafone GmbH has more ...

* Vodafone Romania *

Orange Romania Orange România is a broadband Internet service provider and mobile provider in Romania. It is Romania's largest GSM network operator which is majority owned by Orange S.A., the biggest initial investor, who gradually increased its ownership. Be ...

Orange France Orange S.A. (), formerly France Télécom S.A. (stylized as france telecom) is a French multinational corporation, multinational telecommunications corporation. It has 266 million customers worldwide and employs 89,000 people in France, and 5 ...

* Free France *

SK Telecom SK Telecom Co., Ltd. ( or ) is a South Korean wireless telecommunications operator and former film distributor and is part of the SK Group, one of the country's largest chaebols. It leads the local market with 50.5 percent share as of 2008. S ...

* KT Corporation * LG Uplus *

Deutsche Telekom Deutsche Telekom AG (; short form often just Telekom, DTAG or DT; stylised as ·T·) is a German telecommunications company that is headquartered in Bonn and is the largest telecommunications provider in Europe by revenue. Deutsche Telekom was ...

* KDDI Japan * China Mobile * EE United Kingdom * Vodafone Netherlands * KPN Netherlands *

Airtel India Airtel India is the second largest provider of mobile telephony and third largest provider of fixed telephony in India, and is also a provider of broadband and subscription television services. The brand is operated by several subsidiaries of ...

* A1 Telekom Austria * 3 Austria *

Swisscom Swisscom AG is a major telecommunications provider in Switzerland. Its headquarters are located in Ittigen near Bern. The Swiss government owns 51.0 percent of Swisscom AG. According to its own published data, Swisscom holds a market share of 56 ...

Verizon Communications Verizon Communications Inc., commonly known as Verizon, is an American multinational telecommunications conglomerate and a corporate component of the Dow Jones Industrial Average. The company is headquartered at 1095 Avenue of the Americas i ...

Turkcell Turkcell İletişim Hizmetleri A.Ş. (''lit. Turkcell Communication Services'') (, ) is the leading mobile phone operator of Turkey, based in Istanbul. The company has 39,3 million subscribers as of September 2021. In 2015, the company's number of ...

* TIM *

Wind Tre Wind Tre S.p.A. (formerly H3G S.p.A.) is an Italian telecommunications company of the CK Hutchison Holdings Limited group, which offers mobile and fixed telephony services. It began as a mobile telephone operator in 1999, with the name ''And ...

* Vodafone Idea (V!) India * Telekom Hungary *

Telenor Hungary Yettel Hungary (formerly ''Telenor'', ''Pannon'' and ''Pannon GSM'') is the second largest mobile phone operator in Hungary. Yettel Hungary Ltd. was founded as ''Pannon GSM Telecommunications Ltd.'' in 1994. History In November, 1993 Pannon GSM ...

* Vodafone New Zealand * Magyar Telekom Currently there are about 200 models from different smartphones manufacturers supporting EVS, including: *

Apple An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple fruit tree, trees are agriculture, cultivated worldwide and are the most widely grown species in the genus ''Malus''. The tree originated in Central Asia, wh ...

Samsung The Samsung Group (or simply Samsung) ( ko, 삼성 ) is a South Korean multinational manufacturing conglomerate headquartered in Samsung Town, Seoul, South Korea. It comprises numerous affiliated businesses, most of them united under the ...

Google Google LLC () is an American multinational technology company focusing on search engine technology, online advertising, cloud computing, computer software, quantum computing, e-commerce, artificial intelligence, and consumer electronics. ...

* HTC *

* LG *

Motorola Motorola, Inc. () was an American Multinational corporation, multinational telecommunications company based in Schaumburg, Illinois, United States. After having lost $4.3 billion from 2007 to 2009, the company split into two independent p ...

* Panasonic *

Sony , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...

Xiaomi Corporation (; ), commonly known as Xiaomi and registered as Xiaomi Inc., is a Chinese designer and manufacturer of consumer electronics and related software, home appliances, and household items. Behind Samsung, it is the second largest ma ...

Interoperability

Inter-carrier interoperability is a problem, as calls are by default routed over narrowband type connections which downgrades the voice to narrowband quality vs EVS and

HD Voice Wideband audio, also known as wideband voice or HD voice, is high definition voice quality for telephony audio, contrasted with standard digital telephony "toll quality". It extends the frequency range of audio signals transmitted over telephone ...

™️ even if the individual phones and carrier networks all support EVS. Interoperability was very limited in 2018 and remains so. Thus, users are advised to ditch phone calls for pure VoIP apps such as

FaceTime FaceTime is a Proprietary software, proprietary videotelephony product developed by Apple Inc. FaceTime is available on supported iOS mobile devices running iOS 4 and later and Mac computers that run and later. FaceTime supports any iOS devic ...

, Google Duo,

WhatsApp WhatsApp (also called WhatsApp Messenger) is an internationally available freeware, cross-platform, centralized instant messaging (IM) and voice-over-IP (VoIP) service owned by American company Meta Platforms (formerly Facebook). It allows us ...

, Facebook Messenger, and/or Telegram when voice call quality it poor despite good network connectivity.

Licensing

EVS, like AMR-WB and AMR-WB+, incorporates several

patents A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A p ...

. As with those two codecs, VoiceAge Corporation is in charge of the licensing and offers RAND pricing

References

External links

Enhanced Voice Services Codec for LTE

The 3GPP Enhanced Voice Services (EVS) codec

Fraunhofer Technical Paper – Enhanced Voice Services (EVS) Codec
{{Compression formats Audio codecs Speech codecs Wideband codecs