By: Sue Rudd

Self-Organizing Networks have the potential to rapidly and simultaneously transform network economics and improve customer experience. Two variants of SON – Centralized and Decentralized – focus on different approaches. Network operators need to be aware of their capabilities and consider where each provides the best optimization support. 

SON Systems automate the configuration and optimization of wireless networks to help operators maximize deployed RF and spectrum capacity, simplify Radia Access Network (RAN) management and improve customer experience, all while reducing network OPEX. Complexity and costs associated with network management have been steadily increasing for several years as the number of network parameters to be monitored and 'tuned' has grown exponentially both for the Radia Network Controllers (RNC)/Base stations in 3G networks and for the eNobeB/MME in LTE/4G networks.

Already in 3G networks, it has become useful to automate the optimization of many RF, Controller and Antenna parameters. More recently, SON has become essential as HetNets, small cells and LTE escalate the complexity of RF planning with spectrum re-farming, HetNets and multiple cell types – macro, micro, pico, femto etc. – overlaid in the same or adjacent frequencies. The huge torrents of live network event data that are thrown off by modern HetNets cannot feasibly be processed by human network engineers in the timescales required to manage and optimize these fast- growing mobile broadband networks. RAN automation using SON must become an integral part of making these networks operational.

Three functions of SON

Major infrastructure vendors now offer SON solutions – for instance NSN describes SON’s three functions:

• Self-configuration – for automated setup and configuration with neighboring cells exchanging parameters as needed.
• –Self-optimization – for real-time intelligence and parameter modification including brokering handovers and balancing loads among neighboring cells.
• –Self-healing – to cope with service impacting failure detection and recovery.

Self-configuration based on Automatic Neighbor Relation (ANR) is one of the most deployed SON feature among network operators. SON provides dynamic plug-and-play configuration of newly-deployed RAN elements.

Self-optimization capabilities include optimization of coverage, capacity, handover, and interference. Load balancing is part of the self-optimization functionality, enabling SON systems to identify cells that are experiencing congestion and transfer the traffic load to other cells that have bandwidth. Coverage and capacity optimization enable scheduled correction of bottlenecks in dynamic environments both daily and seasonally.

Finally, self-healing capabilities enable automatic detection and removal of failures.

In announcing its recent deployment of SON for SingTel’s WCDMA network, Nicholas Seow, President and Country Manager of Ericsson Singapore noted, “Network complexity has reached the stage at which self-configuring, self-optimizing and self-healing functions are now indispensable for running a modern mobile network. Multiple standards and an expanding ecosystem of equipment providers need the automation of as much network planning, design, build and optimization as possible."