Publié le 19 avril 2013
The 2013 Transport Networks for Mobile Operators (TNMO) event is taking place in London from April 22 to 24. As a member of the NGMN Alliance, Murat Bilgic, Advisor, CTO Office, EXFO’s Wireless Division, will present the Small Cell and HetNets section of the NGMN RAN Evolution and HetNet Projects Workshop. In order to get the inside scoop, we sat down with Murat.
MAG: Murat, how long has EXFO been a member of the NGMN Alliance and what is its purpose?
MB: EXFO has been a member of NGMN since November 2011. NGMN’s main purpose is to get mobile network operators to develop a shared view of mobile broadband network deployment essentials. NGMN was quite instrumental in the early days of LTE standards development because it convinced many operators to support LTE as the common long term technology platform. Today, it focuses on LTE and its ongoing evolution. The NGMN Alliance includes mobile operators as members and equipment vendors who act as sponsors, and research institutes and universities as advisors. It brings together telecom industry and research partners for the purpose of ensuring successful LTE network deployments.
MAG: Your session is called Small Cell and HetNets. Can you tell us what it’s about?
MB: I am afraid this is going to be a long answer. Understanding the why behind small cells and hetnets is very important. As you know, the primary concern for operators is to provide their customers with an excellent quality of experience as their network load continues to increase year after year. As a matter of fact, the industry’s next foreseeable challenge will be to determine how to scale capacity 1000 fold. There are different timelines associated with this demand curve; some as steep as 1000x in the next 8 years. In order to provide this capacity, operators must employ a three-pronged strategy: increase the spectrum, implement more efficient technologies and deploy denser networks.
The regulatory process for spectrum allocation is quite slow and existing users of most suitable spectrum limit the effectiveness of this capacity increase. As for technologies, we are constantly approaching their theoretical limits and having to overcome the performance limitations of processors, batteries, etc. If anything, the lag between standards development and mass-market products is growing, which leads us to the third prong of the strategy.
At first, mobile operators deploy for coverage. This is done using macro cells; where each cell covers multiple square kilometers. Then, to increase density, they build smaller cells; in many cases, in the area already covered by macro cells. By definition, a small cell covers an area that is substantially smaller than a typical macro cell. Think of them as circles whose radius can range from a few meters (femtocells) to hundreds of meters (outdoor microcells) and whose capacity can range from a handful of users to hundreds.
HetNet, which is short for heterogeneous network, represents the coordinated use of diverse radio technologies (LTE/3G and WiFi in small cells) and cell layers to achieve the desired capacity and coverage. Cell layers determine how to best serve a customer when s/he happens to be covered by both macro and multiple small cells. The strategy is to find the best radio technology and base station to serve the customer’s device at any given time. The decision can be based on multiple factors such as mobility, applications in use as well as the usage and interference levels in macro and small cells. In the next few years, we will begin to see devices that use multiple radio technologies and multiple base stations to communicate simultaneously.
MAG: Why is this important to EXFO?
MB: EXFO has a long history of helping network operators monitor, measure and troubleshoot their IP/Ethernet transport networks. Combined with its fiber-optic expertise, EXFO is well-suited to provide a positive contribution to small cells and hetnets as transport networks get denser.
MAG: Without revealing too much, what is the major takeaway of your session?
MB: Ultimately, the NGMN Alliance relies on input from the industry to progress. This session is an appeal to all those who are interested in joining the cause.
MAG: You’ll be joined by major industry vendors and operators, what do you look forward to learning from their sessions?
MB: Like myself, fellow presenters will be covering new projects that the NGMN Alliance has recently launched. They will also be making appeals to the community for input, especially with respect to transport issues. I look forward to hearing their perspectives on projects like RAN evolution.
MAG: Finally, which major trends do you expect will come out of the TNMO this year?
MB: The increasing importance of transport for RAN will be acknowledged. It is already a major concern because some of the LTE-A features require perfect transport that can only be achieved in point-to-point fiber networks. Given the high cost of such deployments, alternatives are being explored and the exact requirements of transport for LTE-A are being developed. Similarly, cloud RAN also requires a new transport design. I expect these topics to be heavily debated at the event.
Joining Murat at this workshop will be Ran Avital from Ceragon, Paolo Volpato from Alcatel-Lucent, Konstantin Zhevlakov from Deutsche Telekom and Julius Robson from CBNL. This will be an interactive session that will encourage the maximum extrapolation of case studies and knowledge-driven discussion. We invite you to attend Murat’s session on Monday, April 22, at 11:30.