Now small is beautiful for the network too

SIP Unplugged Blogs (Nov 28 2011) Insider Insight

1. 

   As far as mobile handsets go, small has always been beautiful.   And even though the rise of the smartphone has seen a return to larger screen sizes, today’s handsets are still remarkably compact.
   
   Now it seems that as we move towards a data driven, bandwidth hungry 4G or LTE world, small is finally becoming beautiful for the mobile networks as well—beautiful not only in terms of coverage and capacity, but also in terms of cost.
   
   Because nothing boosts network capacity like spectrum re-use and networks of small cells re-use spectrum like no other technology in the world.   So for next generation high-speed mobile data networks to deliver the throughput and penetration required in congested city centers, operators will be looking to deploy a tight pattern of small cells within the overlay macro network.
   
   This approach has been christened the het-net – marketing speak for 'heterogeneous network'. Until relatively recently, the economics of building a cellular network involved throwing large-scale radio footprints across wide areas to create widespread coverage. However, with the world trade body—the GSM Association—predicting as many as 50 billion connected devices by 2020, widespread coverage alone is not enough—tight coverage and greater network capacity is the order of the day.
   
   The het-net is the technical solution to the demand equation—a large-footprint macro network containing a pattern of “ever-decreasing circles” giving additional targeted capacity. These circles will drill down through urban and metro layers to individual offices, shops, homes and high traffic areas such as railway stations, airports and sports venues.
   
   The lessons ip.access has learned from helping to roll out the world’s largest consumer femtocell deployment with AT&T, and also from working with more than 60 mobile operators on public small cell deployments worldwide, are proving to be crucial to the het-net vision and also to the economic arguments.
   
   LTE networks are envisioned as self-organizing, but the rollout of high capacity city center LTE networks with a dense pattern of small-cells in a het-net configuration will present a new and complex series of challenges that engineers will need to address in order to successfully deliver the optimal coverage and capacity benefits. 
   
   The good news is that private small cell deployments in consumer homes (such as the AT&T 3G MicroCell) already depend on self-optimization techniques built into each unit, enabling them to listen to and adjust to their surrounding radio environments.  These capabilities will be a vital attribute in future mobile network design – in a network with a large number of small cells, RF tuning of individual cell sites must be as automated as possible.
   
   At ip.access, we developed our own remote diagnostics tool—termed the OysterCatcher—and with well over half a million small cells deployed globally we have learned a great deal about the performance characteristics of large scale deployments. For example, sometimes seemingly unconnected changes have an unforeseen impact on performance—a new software upgrade for a popular smartphone, for example, might affect the radio performance characteristics of the network and require some intervention. 
   
   Automated optimization built into small cells works very effectively most of the time, but network planners will need to be able to gather detailed information from the small cell layer, analyse it and react quickly across the network to maintain the standards that consumers will demand and expect.
   
   But amid all these requirements to learn new techniques and adjust to new challenges, there is also good news for the operator community as it cements its plans for the 4G world.  The small-cell led roll-out of LTE networks will have a major impact on network investment costs—and in a good way.
   
   Indeed, ip.access believes that the small cell, het-net approach to network roll-out will change forever the way that wireless networks are built and - despite the resultant surge in the number of deployed cell sites—the investment cost of network construction can actually become lower and more manageable.
   
   The rise and success of the consumer femtocell has helped drive down manufacturing costs of these targeted coverage and capacity solutions, and because they use internet grade IP backhaul to connect to the core network the supporting infrastructure costs for these cells is also much lower.  Further, small cells can be deployed with pin point accuracy to exactly match network demand resulting in a much faster return on network infrastructure investment.
   
   What all this means is that as the base cost of a cell site falls to hundreds of dollars rather than tens of thousands of dollars, the savviest network operators will be able to quickly react to network demands, adding additional capacity to match their roll-out much closer to their returns. 
   
   The core technology of the consumer femtocell—originally conceived as a home market solution to black-spots in mobile network coverage—now finds itself in great demand as network operators face up to the challenge of building the advanced networks required to deliver levels of capacity that were beyond the wildest dreams of the most optimistic analyst even just a few short years ago.
   
   DR Andy Tiller, is SVP of Product Strategy & Marketing for ip.access, responsible for the product roadmap, market strategy and communications.  He is a Board member of the Femto Forum, and vice-chairman of Working Group 1 (marketing and promotions). Previously, Andy was CTO and VP Product Marketing for ShoZu, a GSM Award-winning mobile service for sharing videos, photos and other user generated content between mobile phones and dozens of community websites and blogs (including YouTube, Flickr and Blogger).  Andy was responsible for the ShoZu service roadmap, and for the underlying technology. Before ShoZu, Andy was VP of Product Marketing with Geneva Technology, a provider of telecoms billing software, where he helped to create a successful strategy for the company's entry into the mobile billing market. Andy holds a PhD in Theoretical Chemistry from Queens' College, Cambridge.

   Bookmark or Share this article

Login to comment.