For the rest of the Q3 2015 issue of Korea Communication Review magazine please click here

Hear from CTO of Korean Telcos

    1. Dr. Dongmyun Lee, CTO of KT: Leading 5G through wired/wireless Integration

► 2. Mr. Changwoo Lee, CTO of LG U+: LG U+'s Mobile Network Evolution Strategies 

    3. Dr. Jingsung Choi, CTO of SK Telecom: SK Telecom's 5G Evolution Strategies 

According to Mr. Changwoo Lee, Vice President of LG U+ Network Business, expansion of 3-band carrier aggregation (CA) coverage, giga Internet, LTE, and VoLTE are key areas for the company's investment this year. He went on to say, for 5G mobile communication, LG U+ has already began development of a new non-OFDM technology which would be totally different from the current technologies. For LTE-A, the company is enhancing the focus on development of LTE-U and uplink CA technology, he added.

What is your plan for investment this year?

It will be less than last year. First, 3-band CA coverage will be expanded. We have already had a nationwide 3-band CA LTE-A network, but plan to further enhance small cell deployment in shadowed areas and rural areas.
 
Also, investment in giga Internet will be made, especially in 'U+ Optical Giga', our wired giga Internet service. Of course this will include giga Wifi as well. In addition, investment in VoLTE will continue, with its subscription growing steadily.

What is your strategy for 5G?

5G can have more than one concept and definition. To me, what matters most in 5G would be ultra-high capacity, mass connection (for IoT era), and ultra-low latency. In fact, many solutions designed to meet these three requirements have been available.
 
There are two key factors to consider when developing new 5G technologies: technological value and customer value. A new technology is not hard to realize. What's more important eventually is how you make the technology work as a 'new life creator'. A good 5G technology should be able to satisfy at least one of the five core customer values: cost efficiency, time efficiency, emotional satisfaction, safety, and sharing information. The question that we are trying to answer is, if Internet speeds are improved from 100 Mbps to 110 Mbps, what value it would bring to customers. For example, for remote surgery, video transmission in high-quality resolution with no latency is a must. 5G, capable of satisfying two of the technical values (ultra-high capacity and ultra-low latency), can create a new customer value, remote surgery.    

OFDM has become one of the hottest issues in 5G. What is your thoughts about this?

As 5G will have frequency efficiency that is different from that of 4G, the conventional ways used in 4G will not work anymore. 5G should satisfy three conditions: mass connection, ultra-high speed, and ultra-low latency, which would not be met with the current OFDM technologies. For instance, with NOMA, a non-OFDM technology, strength of a frequency spectrum is adjustable. So, two devices can use the same frequency spectrum at the same time, consequently achieving twice the efficiency.
 
Frequency specialists at LG U+ are also working hard on this technology, and we have been in close cooperation with the relevant leading developers in the world. What we have to keep in mind is that a new technology should not be too expensive, or unreliable.

How is your LTE-A development going?

3-band CA is an LTE-A solution as well. More solutions are under development, and they will have to be launched sooner or later. Launching a new solution itself does not mean much. It has to bring some new values to customers. Another new LTE-A solution ready to launch is LTE-U. It uses unlicensed spectrums, which has been traditionally used for Wifi only, for LTE. Technological development is completed, but LTE-U enabled devices are not available yet. LTE-U is designed to improve Internet connection speeds by combining LTE and unlicensed frequency bands. In fact, it can achieve up to 600 Mbps, 8 times faster than the conventional LTE (75 Mbps).

For Uplink CA, equipment is ready, and compatible devices are on the way. Uplink is one of our strengths. Our uplink BW in all frequency bands is twice as wide as our competitors'. Today, everything is uploaded, including selfies, video clips, live broadcasting, etc. As individual users play a larger role in mobile communication, uplinks speeds are becoming more important. For instance, live broadcasting can play a critical part during disaster response.    

The competition in development of NFV solutions is fierce these days.

So far, when a new technology is released, there has been always a device optimized for the particular technology. But, it is practically not possible to buy a new device for every technology being released. For features remotely located in different devices/units to work properly, software-based implementation is needed. This is why NFV technology has become a sought-after technology. NFV enables resources to be dynamically allocated according to communication loads so that users can be served uninterruptedly even in highly-crowded areas. We are currently building an NFV system and it will be ready for test operation by the end of this year.  

One of the benefits of NFV is fast response. With NFV, every time customer demand grows, operators can provide fast platform-based response any time, without having to get additional equipment. For example, if you need an LTE core unit, then it can easily take 3 months. But, with NFV, you can start offering service within 1~2 weeks. If you have an overloaded area, you can virtually connect to a base station in an underloaded area and have equipment there to handle it.   

When do you think VoLTE interworking will be ready?

LG U+ is the world leader in VoLTE. Out of total mobile service subscription, we have the world's highest LTE subscription rate. We have already begun VoLTE interworking with Japan's KDDI, and plan to expand the service in May. Currently, just G Flex 2 phones are VoLTE-compatible, but we will have more models available soon. 
 
Once VoLTE service is launched, a variety of services, including live broadcasting by individual users, will become available. As the government is currently working on making data-based pricing policies, interworking among the Korean big 3 is expected soon. So, it is not a technological matter.  

What would you say is the strength of LG U+?

In the beginning of this year, LG U+ launched 'LB-NOS' system that can provide our 8.8 million users with the best voice call quality. When a user enters an area with weak signal strength, alerts are sent to the system.  It helps us to collect the data and produce a nationwide shadow area map. It is our goal to use this map to proactively respond before reports are made by customers. This feature, already used in our LTE commercial network, is the Korea's and world's first of its kind.    

All of our networks are all IP networks. So this allows all devices such as Homeboy, smartphones and TVs to communicate with each other. For example, in the past, if you recorded something using CCTV, you could watch it at certain places only. But since Internet-enabled CCTV became available, you can watch it on your smartphone anywhere by using services, like 'MomCa'. As an LTE leader, we are leading all-IP networks business as well.