South Korea-based SK Telecom (SKT) and Samsung claimed they are the first in the world to link LTE and 5G networks during an outdoor trial in Seoul.

SKT, the country’s largest mobile operator, demonstrated the interworking between an LTE network using the 2.6GHz band and a pre-standard 5G network making use of the 3.5GHz and 28GHz bands.

Samsung said in a statement a 360-degree virtual reality video was streamed live between a user in a moving car and another at SKT’s headquarters. The trial showed users can experience seamless uninterrupted streaming service when transitioning from 4G to 5G networks and vice versa.

Park Jin-hyo, SVP and head of SKT’s network technology R&D centre, said: “Users will be able to experience seamless communications service regardless of their location with 5G, in which the nationwide deployment of 4G will work together with base stations that support the 3.5GHz band for wide coverage as well as the 28GHz band for ultra-high speed transmission.”

Dongsoo Park, EVP and head of global sales and marketing of Samsung’s networks business, said: “Interworking between 4G and 5G is a prerequisite for the early stage of 5G commercialisation. The success of the test has proved that end-users’ demand for a seamless and better experience can be met, on 4G-5G-intertwined next-generation network.”

The two companies set up a virtualisation network consisting of virtual 4G and 5G cores with software defined network technology. The trial also covered network slicing technology, which can be used by operators to offer different services and service levels, to ensure consistent quality across diverse services.

Continued progress
In June SKT and Samsung completed a trial to deliver end-to-end 5G connectivity using 5G New Radio (NR) technology in the 3.5GHz band and Samsung’s virtualised core and RAN.

In August the operator achieved a low latency rate of 2 milliseconds from handset to base station in a demonstration with vendor Nokia. In February the Korean operator joined Deutsche Telekom and Ericsson to complete tests of what they said was the world’s first intercontinental pre-commercial 5G network, a move which appears to clear the way for enhanced global roaming once the technology is standardised.