SK Telecom announced that, working with Nokia, it has successfully reduced round-trip latency between a handset and a base station to 2 milliseconds over its LTE network.
The latency between the handset and base station for SK Telecom’s existing LTE environment is around 25ms.
SK Telecom and Nokia say they have reduced the latency by applying uplink pre-scheduling (which enables the handset to immediately transmit data to the base station) and short transmission time interval (TTI), which reduces data transmission time between base station and handset to about 1/7th.
SK Telecom says the demo moves the cellco one step closer to realizing 5G. The International Telecommunication Union’s definition of 5G calls for ultra-low latency of 1ms.
|Speed||Latency (from handset to base station)|
|2G||14.4kbps ~ 64kbps||300 ~ 1000ms|
|3G||144kbps ~ 14.4Mbps||50 ~ 100ms|
|4G||75Mbps ~||25ms or lower|
|5G||20Gbps ~||1ms or lower|
LTE’s current round-trip latency of 25ms can support two-way communication services like remote learning and smart work, but not services that require real-time transmission of data such as autonomous driving and telemedicine.
SK Telecom says that reducing LTE latency to 2ms will enable LTE to support real-time 5G services such as autonomous driving, real-time monitoring of remote sites, and AR/VR services.