Long term evolution (LTE) addresses the issue of growth in data traffic over networks designed for voice. However, deploying LTE has its own set of issues that need to be addressed.
Market and commercial drivers
The recent introduction of mobile internet services by wireless service providers has added a large amount of traffic to the networks. Most of this new traffic is data rather than traditional voice or messaging. This growth is expected to continue, possibly reaching triple digits.
Much of the growth has been driven by new social network services and applications as well as email and location-based services like Google Maps and Bing, all of which require consistently connected data connections.
The problem is that these networks were designed for voice rather than data services. Radio interference limits the amount of data traffic within the current spectrum. At the same time, increasing the overall size of these networks to accommodate the demand would make mobile services uneconomical for communication service providers (CSPs).
LTE technology aims to address this problem through a combination of simplifying the backhaul network, removing the need for complex control functions and using cheaper transport technology to reduce the price per port for connections from the cell sites to the core network.
Technology impact of LTE
LTE technology addresses the radio interference issue by allowing much more efficient use of cell capacity. It also simplifies the access network by removing layers (radio network controllers) and increases the complexity of the enhanced Node B by making it responsible for call handoffs between cells.
CSPs will now need to extend their IP networks all the way to the cell site as these radio changes are often isolated from the rest of the network. This will require a complex audit of every existing cell site location.
LTE will speed up migration to IP technology within the core network but will not require a major restructuring. Most of the impact of LTE will be seen in the backhaul network.
Impact on operational systems
Radio planning will need modification to support the potential volume and high frequency of optimisation. There will be a greater need for backhaul planning processes to be closely linked to radio planning process. This is because the frequency of changes at the radio interface will be much higher and will have a direct impact on the ability of the access network to support traffic demands.
Even while using leased or rented backhaul delivery, bad planning can increase the price of services by 10-20 per cent. Therefore, no matter what backhaul technology is used, ordering with lead times in mind is essential.
The operational systems will also require new algorithms and rules to support the new limits of LTE. Backhaul planning platforms will need upgrading to support IP configuration and quality of service.
Direct interfaces between radio planning, logical demand and build-out functions will be required to reduce errors during handover. This will result in faster planning of cycle times for the roll out of new equipment.
The introduction of policy platforms (such as Policy and Charging Rules Function) should make users’ transition as smooth as possible. However, CSPs will need to move from protocol-based charging to a more flexible, dynamic charging model to support new services.
Also, the extended use of IP will require the enhancement of fault and performance tools from the core to the access network. The wider definition of a service will further increase the need for true service quality management over just service level agreements.
Conclusion
The biggest impact of LTE will be in the areas of planning and service quality management. Greater integration will be needed between the radio and backhaul systems and departments. In meeting the demand for higher bandwidth, operators will need to use better processes and find common practices that reduce the costs of managing the rollout.