Samsung Electronics and SK Telecom have launched South Korea's first LTE-R service, the companies announced.
The LTE-R network has been deployed in Line 1 of South Korea's Busan Metro, which is 40.48 kilometers long and covers 40 stations in the region.
SK Telecom started deploying the network for testing in February.
The companies replaced existing analogue wireless technology used by railway personnel there.
The new digital network will allow smooth mission-critical communications between train personnel and control centres using real-time multimedia group calls and texts on top of existing voice calls.
The government plans to deploy more LTE-R networks with the goal to cover 5,600 kilometers by 2025.
It is being deployed for high-speed trains that connect the cities of Wonju and Gangneung.