This is the first time such a call has ever been achieved in Europe. The call was made over Swisscom’s LTE-M network, using a u-blox LTE-M evaluation kit. It followed on from preliminary tests that had been conducted at Swisscom’s laboratories and live network, where an array of different voice-related alarm and emergency functions were all validated. The test configurations included calls from a mobile handset to a landline phone, a landline phone to a mobile, and mobile to mobile, as well as hand-over switching between multiple LTE-M base stations.
VoLTE enables voice communication on packet-switched 4G networks. Being able to deliver voice calls directly over LTE-M represents a major technological advance for the industry. Such LPWAN networks are designed to prolong the battery life of IoT devices and provide better in-building coverage. It also means that circuit-switched 2G or 3G voice connections no longer have to be relied upon, and the necessary infrastructure can be significantly reduced. Consequently the costs that OEMs face, in terms of constituent hardware and implementation effort, can be dramatically reduced. Furthermore, it ensures that OEMs have future proofed themselves against the planned shutdown by many operators of their legacy 2G services.
Building automation, connected health and automotive are among the sectors that can derive benefits from VoLTE utilizing LTE-M. Key use cases include mobile personal emergency response monitors (for the elderly), connected elevators, car crash reporting mechanisms, fire prevention, residential security and numerous other IoT-related applications where there are both power consumption and resource constraints to factor in, but a certain degree of voice interaction would be of value.