Saturday, October 24, 2009

Voice over LTE via Generic Access (VoLGA) Architecture

LteWorld has recently published a short tutorial about VoLGA architecture as shown below.

For more details click here.

Sunday, October 11, 2009

Self-configuring and self-optimizing Networks in LTE

Self-configuring, self-optimizing wireless networks is not a new concept but as the mobile networks are evolving towards 4G LTE networks, introduction of self configuring and self optimizing mechanisms is needed to minimize operational efforts. A self optimizing function would increase network performance and quality reacting to dynamic processes in the network.

This would minimize the life cycle cost of running a network by eliminating manual configuration of equipment at the time of deployment, right through to dynamically optimizing radio network performance during operation. Ultimately it will reduce the unit cost and retail price of wireless data services.

As per 3GPP standards, a typical operational objective is to optimize the network according to coverage and capacity.

Providing optimal coverage requires that in the area, where LTE system is offered, users can establish and maintain connections with acceptable or default service quality, according to operator’s requirements. Coverage and capacity are linked, a trade-off between the two of them may also be a subject of optimization.

To achieve these objectives, 3GPP suggests to implement following functions
  • Detection of unintended holes in the coverage (planned by the operator)
  • Perform coverage optimization, including DL/UL channel coverage a
  • Ability to balance the trade-off between coverage and capacity

Once solution is implemented, it would result in
  • Continuous, optimized and matched UL and DL coverage
  • Optimized DL and UL capacity of the system
  • Balanced tradeoff between coverage and capacity
  • Interference reduction
  • Controlled cell edge performance
  • Minimized human intervention in network management and optimization tasks
  • Energy savings

Implementing self configuration and self optimization under multi vendor environment is challenging task. For this purpose, It is of importance that measurements and performance data of different vendors follow same standard. Especially when the interaction between self configuring/optimizing networks and O&M has to be considered.