South Korea's SK Telecom claims to have successfully completed a field trial of 28GHz-based 5G services, describing it as a "key milestone" in the commercialization of 5G.

The telco says it has been working on the trials with local vendor Samsung Electronics Co. Ltd. (Korea: SEC) since October last year and that results will help it to develop 5G pilot networks before the end of 2016.

The trials of so-called millimeter wave (mmWave) technologies -- which use spectrum bands above the 6GHz range -- were conducted using outdoor 5G basestations and a vehicle fitted with a 5G test handset, said the operator in a statement.

The aim was to measure performance criteria such as coverage, transmission speed, latency and radio strength, although SK Telecom did not provide details of any metrics.

During the trials, the operator also took advantage of a technique called 3D beamforming, which is designed to compensate for the radio propagation path loss that occurs in higher frequency bands.

Spectrum in this range is capable of supporting much higher-speed connections than are possible using lower frequency bands, although it is not as good at providing indoor coverage or serving wide areas.

SK Telecom (Nasdaq: SKM) has previously announced plans to have some kind of 5G service in operation for the Winter Olympics that will take place in Pyeongchang in 2018.

Several other Tier 1 service providers have announced similar plans over the next few years, including Japan's NTT DoCoMo Inc. (NYSE: DCM), US operators AT&T Inc. (NYSE: T) and Verizon Communications Inc. (NYSE: VZ), Russia's Mobile TeleSystems OJSC (MTS) (NYSE: MBT) and MegaFon and Sweden's Telia Company . (See AT&T Lights Fire Under 5G, Plans 2016 Trials, TeliaSonera, Ericsson Join 5G Early Movers, Russia's MTS to Trial 5G in 2018, Verizon CEO: US Commercial 5G Starts in 2017 and DoCoMo & EE Share 5G Visions.)

The first 5G standards are not expected to appear until 2020, however.

Unlike earlier generations of mobile network technology, which focused on improvements to the air interface, 5G encompasses the use of software and virtualization technologies in the core network as well as a higher-speed and lower-latency radio system. (See Tele2 Gets 5G-Ready With NFV Moves and NFV Key to 5G Business Case, Says TeliaSonera.)

— Iain Morris, , News Editor, Light Reading