Ericsson Wi-Fi Calling

Wi-Fi calling enables a simple and cost efficient way to extend operator voice coverage. It could also be used to allow more affordable ways to communicate when traveling abroad. With Wi-Fi calling for multi-device, operators can extend voice services to smartphones, tablets, computers, smartwatches and other personal devices.

Market situation

There are areas where operators might find it difficult to provide good coverage, due to technical, economic or legal reasons. This may include remote urban areas, well insulated buildings, in particular, indoor areas like basements as well as areas where the operator lacks radio licenses and thereby fully relies on inter-carrier roaming. In the past, this was handled by for example Femto-cells or other costly arrangements. However, most places where people spend their time are already covered by Wi-Fi access.

Nowadays most smartphone vendors have introduced built-in support for Evolved Packet Core (EPC) integrated Wi-Fi calling support as part of their device fleet. This provides users with native Wi-Fi calling experience without any need to download smartphone apps, but instead user can continue using the built-in phone dialer and continue to be reached on their phone number.

Ericsson's Wi-Fi calling offering

Wi-Fi calling enables a simple and cost efficient way to extend operator voice coverage to users’ home. It can also be an attractive way to offer affordable international roaming. With the new capability to also extend this service to devices without a SIM-card, operators can reach even more devices in the users’ homes.

  • Indoor coverage is key to mobile workers and home residents. 
  • No roaming cost for the operators opens up for attractive end-user pricing when the user is outside home operator coverage. 
  • Ericsson Wif-Fi calling enables the use of complementing devices without a SIM-card also for operator communication services. This will increase the number of connected devices and thus increases the number of completed calls. 
  • Green button experience with smartphone dialer with native support in device and seamless handover to VoLTE

Operator benefits

Wi-Fi calling allows operators to reduce churn and attract new customers as well as increase usage by extending service reach: 

  • Improving user satisfaction with enhanced voice and video calling coverage in users’ homes and in small enterprises over their own Wi-Fi access points 
  • Extending the reach of operator voice services to more types of devices like smartphones, tablets, personal computers etc. 
  • Providing attractive combined voice+data+roaming bundles that makes OTT voice services obsolete with ease-of-use and high quality voice and communication services everywhere. 
Wi-Fi calling enables cost-efficient deployment of extended voice coverage and fast-time to-market:  
  • Re-use existing Wi-Fi coverage rather than deploying costly Femto coverage 
  • Support natively integrated Wi-Fi calling in devices and network. This reduces operator costs for developing and maintaining separate voice roaming apps 
  • Network efficiency with a common core network for all services – Wi-Fi calling, VoLTE and video calling.

User benefits

With Wi-Fi calling consumers can use their smartphones and other personal devices for operator communication services while using Wi-Fi access and existing mobile phone number. This is beneficial to users that suffer from poor residential cellular coverage. The devices connect via the Wi-Fi access point in the users’ homes and connect automatically to the operator provided voice service. Users can also make operator voice calls at Wi-Fi hotspots across the world. Users can enjoy voice and video calling (if supported by the specific device), and for operator has launched VoLTE seamless handover of ongoing calls between Wi-Fi and LTE is supported.

With the latest upgrade of the Ericsson Wi-Fi calling solution operator voice services can now also be supported on devices without a SIM-card. Users can make operator voice calls over any Wi-Fi access point using Wi-Fi only devices, e.g. tablets and laptops. The devices need new software to enable this new service, which is supplied in line with the device ecosystem developments. The user’s personal devices can be located at different Wi-Fi access points. The smartphone can also be on cellular access, and the user can pick-up calls on any of these devices. Users can transfer ongoing calls between devices and simultaneous calls using the same mobile phone number can be made.

Solution overview - Wi-Fi calling for smartphones

Ericsson offers an end-to-end Wi-Fi calling solution for smartphones, as well as for multi-device capabilities, based on Evolved Packet Core (EPC), Ericsson IP Multimedia Subsystem (IMS) and OSS/BSS. The solution is verified towards device brands that support native Wi-Fi calling capabilities on different devices.

Wi-Fi calling is based on 3GPP standards. Devices have to support natively integrated Wi-Fi calling functionality. The network has to have appropriate functionality enabled in the Evolved Packet Core (EPC) and IP Multimedia Subsystem (IMS).

Ericsson’s pre-verified in-house-built end-to-end Wi-Fi calling solution enables fast and smooth network deployment:

For seamless VoLTE to Wi-Fi calling handover, functionality is provided in the:

Solution overview - Wi-Fi calling for multi-device

To support Wi-Fi calling for multi-device Ericsson has developed an adapted solution building on the existing Ericsson Wi-Fi calling solution. The solution is offered to operators as a complete end-to-end solution including system integration services. The solution includes Evolved Packet Core (EPC), IP Multimedia Subsystem (IMS), User Data Management (UDM) and OSS/BSS. The solution is verified towards device brands that support these capabilities.

Ericsson solution advantages

Ericsson Wi-Fi calling offering is verified together with major device and chipset suppliers. This secures a smooth deployment, operation and future evolution of the Wi-Fi calling offering.

Ericsson provides an end-to-end Wi-Fi calling offering, including IMS, EPC, subscriber data management and professional services.

Ericsson has provided equipment to a majority of the launched networks of EPC integrated Wi-Fi calling.

Wi-Fi calling in relation to voice over LTE (VoLTE)

Both VoLTE and Wi-Fi calling rely on an IP Multimedia Subsystem (IMS) network to deliver the voice services, and other communication services like video calling. Operators that have launched VoLTE over their LTE network (the telephony service is delivered via the IMS network), could extend the same voice service (same SIM) into buildings using Wi-Fi when LTE coverage is poor.

Operators that have not yet launched VoLTE, can start to offer IMS based Wi-Fi calling services to users who have poor cellular 2G/3G coverage indoor in homes and small enterprises. When operators later deploy VoLTE, the voice service will work seamlessly between LTE and Wi-Fi access.