We have witnessed an accelerated increase in worldwide commercial deployment of VoLTE since 2016. According to the statistics from GSA, the number of commercial VoLTE networks reached 176 by the end of 2018, with 50 networks rolled out in 2018 alone. More than 100 operators are currently investing in VoLTE and preparing to launch commercial VoLTE service nationwide. By 2021, the world will have over 300 commercial VoLTE networks.

LTE Will Replace 2G and 3G as the Foundation Network in the LTE Evolution Era.

Why has VoLTE commercialization dramatically accelerated in the past two years? The dramatic growth of VoLTE is an outcome of the increasingly mature VoLTE industry chain. The industry chain has made substantial advancements in networks, terminals, and value exploration to support continuous evolution.

Currently, 2G, 3G, and LTE networks coexist. Their operating expense (OPEX) accounts for more than 60% of the total cost operation (TCO) for operators. After 5G is put into commercial use, if all of the four types of networks are deployed for a single operator, the OPEX will be even higher. To improve operation efficiency, 2G and 3G networks will be gradually shut down with the voice, data, and IoT services being migrated to LTE networks, which feature better spectral efficiency. Network simplification is the way of future.

Dozens of operators, such as AT&T in the US, Vodafone in Australia, and TELUS, Bell in Canada, M1,Singtel,StarHub in Singapore  have shut down their 2G networks. Most other operators have released network shutdown plans. The years from 2020 to 2025 will witness large-scale shutdown of 2G and 3G networks.

LTE serves huge number of subscribers and provides most of the traffic and services. It is still the main revenue source for operators. Strategy Analytics forecast shows that by 2022, LTE will contribute to 80% of operators’ mobile communication revenue. In particular, mobile voice services will still be a major cash cow for operators. VoLTE, as an evolved voice technology, offers ultimate voice and video service experience and will create greater business value for operators.

In the LTE evolution era, LTE will replace the 2G and 3G networks as the foundation network. According to 3GPP specifications, VoLTE will become a fundamental technology for Mobile voice calls. Although LTE has developed for nearly 10 years, and the LTE coverage is not as good as that of 2G networks. Insufficient coverage causes LTE subscribers to fall back to the 2G or 3G networks, resulting in significant user experience changes. It also leads to congestion on the 2G and 3G networks and makes it difficult to release spectrum used by 2G and 3G. To achieve zero fallback, operators can make refarm low frequency bands, fill coverage holes, and take other measures to ensure wider coverage in rural areas and deeper coverage in urban areas. by this way, the 2G and 3G spectrum resources can be released to ensure that data, Voice, and IoT services always camp on the LTE network and will never fall back to the 2G or 3G network. This also encourages the 2G and 3G subscribers to migrate to 4G networks. In the future ,VoLTE will definitely become a necessity for constructing an intelligent, simplified, and reshaped target network, an LTE+NR network.

Continuous VoLTE Evolution Enables a New Era of HD Voice and Superior Experience.

The VoLTE solution evolves from circuit switched (CS) to all-IP VoLTE networks to provide HD voice, HD video, and rich media services for subscribers. This solution retains and consolidates voice services to help operators construct a future-proof network.

Improved spectral efficiency

VoLTE can provide additional benefits by accelerating spectrum refarming and subscriber migration. The spectral efficiency of VoLTE is twice to four times that of 2G and 3G networks. This indicates that only a limited amount of spectrum is required for voice service provisioning. The remaining precious spectrum resources can be allocated for 4G data, IoT and a multitude of other new services to increase operator revenue.

Enhanced coverage

Voice service provisioning remains one of the core tools at an operator’s disposal to maintain a competitive edge. Already over 60% of the world’s population is covered by 4G networks. The 4G penetration rate has remarkably exceeded 95% in a number of developed areas. The rapid growth of 4G networks has offered a favorable network foundation for nationwide large-scale commercial deployments of VoLTE. Currently, there are 18 operators who have more than a million VoLTE subscribers and keep attracting more subscribers. By December 2018, the number of VoLTE subscribers in China has exceeded 330 million.

Huawei has launched the VoLTE Plus solution that incorporates transmission time interval bundling (TTI bundling), VoLTE coordinated multipoint transmission/reception (VoLTE CoMP), and other significant features to help operators establish top-quality VoLTE networks with enhanced coverage. The commercial networks in Sweden and Canada show that the VoLTE network offers better coverage than the intra-frequency UMTS network and VoLTE achieves a mean opinion score (MOS) much higher than the UMTS in terms of voice services.

HD voice for superior experience

The HD voice services offered by VoLTE are much better than GSM or UMTS voice services. The VoLTE call delay is less than 1/3 of CS call delay in GSM or UMTS networks, greatly improving user experience with voice services. VoLTE can provide high value services in addition to plain voice, such as EVS HD voice, H.265 HD video, rich media (RCS, UC, and CaaS), multi-screen and multi-device services. With VoLTE, subscribers enjoy superior communications service experience. The Huawei VoLTE Plus solution not only improves the VoLTE coverage but also ensures VoLTE voice quality in strong-interference, heavy-traffic, and other typical scenarios. This helps operators build an optimal VoLTE network meeting the requirements of “three Always”, that is, Always On LTE, Always On MOS4.0, and Always Online. Coverage and voice quality are the most important factors in meeting these requirements.

Easy deployment

The Huawei VoLTE solution has little impact on the existing network, such as CS and IT system. VoLTE networks can be flexibly and quickly deployed to be adapted to terminals. The solution helps operators rapidly roll out commercial VoLTE networks and develop significant brand influence.

The Rapidly Growing Industry Chain for Commercial VoLTE Terminals Becomes Increasingly Mature.

With the rapid development of the industry chain for commercial VoLTE terminals over the past two years, VoLTE is no longer exclusive to mid-range and high-end terminals. VoLTE can now be easily found in a vast number of entry-level terminals. There are up to 1892 entry-level, mid-range, and high-end VoLTE-capable commercial terminal models and 29 VoLTE-enabled chip models worldwide. VoLTE mobile phones account for over 40% of the international shipment of 4G terminals. As predicted by Counterpoint, a third-party consulting firm, VoLTE feature phones will secure a dominant position in the basic voice communication market, with a shipment of over 500 million over the next five years. The reasonably priced VoLTE feature phones receive popularity among voice service consumers for their simplified functions and easy-to-use experience, perfectly meeting the communications requirements of these consumers. The large-scale shipment of VoLTE feature phones assists operators in migrating 2G and 3G subscribers to 4G networks, creating room for quicker spectrum refarming.

Chen Chuanfei, Product Director of Huawei LTE FDD Product Line, said, “VoLTE can fully utilize the spectrum of LTE and provide better and diverse voice services to support continuous evolution. It has been widely recognized as the ultimate voice solution in the LTE business connected network. Huawei will continue to focus on customer strategies and pain points and provide more competitive VoLTE Plus solutions. We aim to help operators build high-quality networks providing superior coverage and user experience, maximize spectrum value, and achieve greater business success.”