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LTE (News - Alert), Wi-Fi, and cloud. Nokia Siemens Network’s new networking concept, Flexi Zone, which was unveiled at Mobile World Congress (News - Alert), has it all. By using a concept from cloud computing called “fabric” and redefining the idea for mobile broadband, NSN has developed a solution to boost indoor coverage while cutting costs in half. “Flexi Zone leverages the capabilities of small cells to create a seamless hot zone for a superior mobile broadband experience,” stated Thorsten Robrecht, head of Network Systems production management.

Flexi Zone technology utilizes multiple technologies that have not yet been implemented on a large scale with any mobile network. First, the technology utilizes clusters of small cells beneath the macro-cellular towers to create a multi-layered network. The small cells enable both coverage and capacity indoors, doing the heavy bandwidth lifting in high-traffic areas.

Second, Flexi Zone would utilize cloud RAN technology to provide its small cells with the scalability of the cloud. Flexi Zone would leave a limited amount of baseband capacity to support normal conditions. When traffic accelerated, the cloud would take over and take on the congestion in a cell. This means that, when installing the small cells, the cells do not have to be overbuilt to handle high-traffic situations.

To deal with the backhaul limitations of small cells, NSN would use radio to backhaul other radio, much like metro Wi-Fi blankets do. The nodes will be connected via LTE and 802.11n links, requiring only a wall outlet for activation. To avoid a mess associated with interference, NSN has introduced the concept of a self-organizing network. The SON would allow the small cells to become self-aware enough to recognize other cells nearby. SON would also allow cells to both grow and shrink dynamically depending on traffic needs.

Because Flexi Zone technology makes heavy use of Wi-Fi, operators can tap into the spectrum and use cheap Wi-Fi equipment to add a great deal of capacity to their networks at a low cost. The technology looks somewhat like the distributed antenna system, except that hundreds of small cells are packed into an area. This concept shapes coverage to the exact outlines of the campus building, sports arena or shopping mall in which it is deployed.

“Flexi Zone is the first small cells implementation using Liquid Radio baseband pooling, with a novel architecture that simplifies the deployment and operation of a small cell network,” said Robrecht. “It’s the perfect answer to the conundrum facing operators who must constantly scale up network capacity to meet booming demand, while at the same time limiting their costs.”