Linkem to Expand 4G LTE Coverage

Linkem is a leading provider of wireless broadband services in Italy. Its 3.5 GHz network covers every region of the country. Linkem provides high-speed wireless data services to individuals and businesses. Recently, ZTE TECHNOLOGIES interviewed Rino Buccio, CTO of Linkem. He discussed Linkem's business focus, WiMAX challenges and services. He also talked about Linkem's transition from WiMAX to LTE and gave his opinion on GTI 2015.

Q: What is Linkem's main business focus?

A: Our main focus is to create value from our spectrum in Band 42, i.e., 3.5 GHz. When Linkem was established in the late 1990s, we started with WiFi. We were the first company in Italy to provide WiFi services for business travelers in the main Italian airports addressing surging demand for mobile data. Few years later, Linkem expanded its business model, offering broadband services to residential customers by using unlicensed 5.4 GHz spectrum. Finally, in 2008, the 3.5 GHz spectrum was auctioned in Italy, and Linkem was able to acquire a portion of the available 120 MHz. During the years, additional portions of the spectrum were added, as consequence Linkem owns 84 MHz of Band 42 today in most of the country. With this spectrum, we deliver wireless broadband internet access.

Q: How do you position yourself in the Italian telecom market?

A: Italy is currently in the process towards digital society. In fact, residential broadband penetration in Italy is about 55 percent. The main reason for that is the resistance to technology introduction, in Italy, more than 20 percent of the population is over 65. In addition, the wired infrastructures are not well developed.
The only infrastructure for residential broadband is copper. The evolution to fiber, with exception of Milan city, is slow. As consequence, the wireless technologies due to their flexibility, low capex per user and high deployment speed are an effective alternative for delivering broadband services to Italian families.
Our positioning is very simple: good performance at a convenient price, simple and transparent offers, optional prepaid services avoiding fixed line monthly fee, service installation within one week.

Q: How would you assess your 4G LTE performance?

A: In 2008, we started delivering broadband wireless services on 3.5 GHz using WiMAX mobile technology. This was quite successful; we acquired a significant customer base. In 2013, we decided to evolve our network from WiMAX to LTE.
From a technology perspective, there is not a big difference between LTE and WiMAX, so we can use all our experience. The evolution to LTE will increase the network efficiency by 250%, enabling us to offer services with higher speed, more capacity, lower latency and enhanced security.
We launched our LTE services in December 2014. Currently, the KPIs are in line with expectations. Both the speed and the capacity have increased more than 50 percent. LTE introduction is fully transparent to our customers, because for the past two years we have delivered dual-mode terminals that are enabling smooth transition.
We are currently focusing on introducing new functionalities and features once we have achieved maximum performance from standard LTE and proper network design. In particular, we plan to commercialize carrier aggregation in the fourth quarter 2015. At the same time, we'll introduce CoMP and beamforming in the main scope for interference reduction on the edge cell to bring spectral efficiency to the final result.

Q: What have been the key factors in your successful transition from WiMAX to LTE?

A: Linkem's transition from WiMAX to LTE is quite peculiar. Normally, other mobile operators use a clean new spectrum to build their LTE network.
Firstly, we need to re-farm our WiMAX networks to free up 20 MHz for LTE, while making sure that the customers receive the same level of service. Then we implement an LTE overlay. Finally, we move WiMAX customers to the LTE layer as quickly as possible.
At present, we have implemented the LTE layer on 50% of the network.

Q: What challenges have you faced in this transition?

A: There are some LTE frame configurations that are fully compatible with WiMAX. Both the networks are TDD, they are fully synchronized. We can run the two networks without losing spectrum in guard band.
However, we are losing a small degree of efficiency because the LTE operates in reuse 1 while WiMAX in reuse 3, as consequence the infrastructure is not optimal for the LTE layer. When we overlay LTE on the infrastructure designed for WiMAX, we have to develop a very accurate planning to limit the interference.
Network security and customer network access are treated differently in WiMAX and LTE. However, with LTE SIM card security, it's much easier to address compared to WiMAX authentication methodology.
We also experienced, differently from WiMAX, full interoperability between the terminals and RAN, and RAN and EPC.
In addition, we are leveraging all the LTE QoS functionality. In fact, we have built a service platform that dynamically set a range of different QoS levels to differentiate applications and dramatically improve user experience. For instance, in LTE network streaming, HD streaming is rapidly increasing in respect to standard definition streaming, which is generally used in WiMAX network. This effect is not only due to increased capacity, the QoS allows more fluid and nice experience in video streaming. It is changing user behavior.

Q: What are Linkem's latest services and how have customers responded to them?

A: Since we launched WiMAX, Italian customers have responded quite well, and our customer base has been growing rapidly.
With LTE network, the customer growth rate on new LTE sites has doubled compared with the opening of new WiMAX site in the past.
The speed with which customer arrive on new sites indicates the enthusiastic acceptance of our services. Therefore, LTE has improved our brand awareness and customers' confidence in our company and network.

Q: What steps should be taken to improve user experience?

A: We spend all day trying to understand what the customer experience is, how the QoS platform needs to be tuned and which application in the network makes the difference. Through continuous engagement of our internal customer service, and key information collection directly from customers every day, we try to understand how to continuously improve.
To explain this, let's look to streaming application. In the WiMAX network, we are measuring 40 to 45 percent of streaming traffic during peak time. With LTE, we are measuring up to 70 percent of traffic. We can see that customers with LTE service make more than 50 percent of traffic at peak time.
We're convinced that in some way, the offered services change customers' demands, enabling different behaviors and life styles.
Everyone knows the amazing projection of mobile traffic over the next decade. We believe that this traffic refers substantially to mobile terminals that will become more and more pervasive. The question is: which networks will this huge traffic impact?
We tried to understand where the traffic is generated by mobile terminals. We realized that only a small proportion of this traffic goes on the mobile networks, about three quarters of it is being generated on indoor WiFi networks, in the office, venues and events, and generally in people aggregation points.
In conclusion, the increase of traffic generated by mobile terminals will partially impact mobile networks, since most of this traffic will go on WiFi accesses by connecting to internet through a variety of fixed and wireless networks.
Nevertheless, the resulting increase of mobile network traffic will require more spectrum by introducing new technology. This will imply using higher band, such as Band 42 or Band 43. However, these bands are limited in terms of penetration and propagation. This prevents to deliver the best indoor user experience everywhere especially during peak time. Band 42 and Band 43 will be certainly used to increase the capacity of mobile networks, but it will be challenging and expensive to ensure mobility and seamless service everywhere, as consequence, it will be efficient only in the dense urban areas where most of capacity is demanded.
Another possibility for 3.5 GHz in mobile network will be business district, college, stadium or any place where many people concentrate. However, the use of Band 42 will also depend on the evolution of the mobile terminals. The main challenges are keeping them switched on many radios, thermal dissipation and batteries capacity.
Our idea is to deliver to customers modems that can work on Band 42. In our model, some of these are indoor modems with multiple high gain antenna systems. They can offer better radio performances than mobile terminals. The remaining of these are outdoor modems that receive radio signals not attenuated by walls. They can improve network coverage and spectral efficiency. All modems offer to our customer state of the art WiFi access, enabling connectivity and best performances to any kind of device as long as it has WiFi.
We are trying to leverage Band 42 to offer affordable and inclusive residential broadband services, and give customers the best user experience with any terminal they may have, as complement to mobility.

Q: What products are you going to introduce in the near future?

A: This touches on the subject of the role of telecom operators and monetizes the network's features and functionality.
Our position is based on simplicity. We like to give our customers very clear offers and services. Our main goal is to deliver very good internet access and enable customers to freely use all the applications they like.
In future, maybe eMBMS could add some distinctive content to our offer.

Q: What are Linkem's goals over the next three to five years and how will you achieve them?

A: We intend to expand our network coverage from current 40 percent to about 80 percent of the population, including biggest cities.
We will leverage on LTE technology to deliver as much capacity as possible from the spectrum we have.
We'll also bear in mind that user experience is not only about speed but also enjoying applications in the best possible way; we will keep differentiating traffic by QoS so that everybody can have the best experience.
Finally, we need to keep our model simple and sustainable to offer competitive price and inclusive services. We strongly believe in LTE-TDD technology, which will be the base for next 5G world, and we will further improve the effectiveness of Band 42.

Q: What impressed you most about GTI 2015?

A: GTI is very important to sustain and develop the knowledge and the culture about TDD. I've been working in the European telecom sector all my life, the last ten years with 3.5 GHz radio. There is a clear perception of cultural heritage that prevents European operators from really understanding the benefits of TDD technology.
Nowadays, it is clear that most of the evolution towards 5G will come through TDD. The number of TDD users and networks will increase dramatically; GTI will be instrumental to keep everyone informed and to communicate effectively about the advantages of TDD.
As telecom operators, we have many challenges. Among others, we need to protect our investment. Sometimes, the technology evolves too fast for the business model, and the potential value of the technology is not fully exploited. We also need to manage complexity arising from managing many spectrums at the same time. This takes away energy and money that would otherwise be directed towards customers
and services.
A global standard is essential. A shared vision of the networks in all countries is also important. GTI is intended to help manage network complexity and ensure that telecom networks remains efficient and sustainable despite the continuous investment needed to cope with technology evolution.
I see the importance of GTI is to facilitate a global approach and make sure that the ecosystem is heading in the right direction. An excellent work has been done to develop the ecosystem for TDD up to Band 41. Band 42 will come soon for mobile, and I truly believe we’re on the right path.