Have you ever found many of cells with very low traffic utilization when assessing system load? What about amount of cells with very high traffic utilization? It is often occurred both on new mobile operator or the mature one, whilst network utilization already in line with the design target.
Lack of accuracy of the design inputs or assumptions (i.e. traffic model) in network design phase for new network deployment, fast increment or degradation amount of subscribers on particular provider due to end of promotion or other reason causing churn, global economic changing, and soon, it can be many reasons trigger non-optimized resource utilization. These all mean missing direction in addressing cost of investment for infrastructure (e.g. CAPEX), in contrary mobile operator able to allocate them for subscriber acquisition cost which is remain high for 2G network.
As the network owner or managed service provider, you can start to intensively evaluate whether resource utilization of your network have been optimized or not yet by simply go to cell level load assessment rather than rely on network level utilization. The following techniques are recommended to maximizing radio resource utilization:
Market Research
Through market research able to provide update data of potential subscriber demand which increase accurateness of traffic model or other inputs to size the network capacity as required. You can’t just relay on the ongoing rollout process base on non up to date market data. Do your market research in more detail with help of specialized third parties in market survey.
Radio Resource Management Features
How efficient RRM features within the base station sub-system have been implemented? You check whether very useful radio resource management features have been implemented or not. Consider to activate network feature such queuing, preemption, directed retry, traffic handover, PS and CS dynamic resource allocation, etc. Define its efficiency metric for each function to keep them active or need to be stopped.
Capacity Enhancement
Quick capacity enhancement through new channel coding such half rate or dual rate can be a tradeoff between quality and capacity. However this way shall be used as temporary solution. Considering to deploying AMR will able to compensate loss of quality while providing higher capacity when it is combined with half rate coding. Reconfiguration of traffic channel or signaling channel can also be performed with less capacity gain. In medium to long term period, utilization issue might be solved through introduction of new cell or site, or simply TRX expansion.
Load Balancing
Shifting traffic from one cell to other cell known as load balancing can be done through many ways such: idle and dedicated radio parameters tuning in single or dual band network, coverage tuning with antenna setting adjustment, traffic sharing through handover due to traffic, etc. These are major activities during tuning activity to relief capacity issues such high blocking, very low or high utilization.
Capacity Balancing
Identification of cells that having condition of very low and high traffic utilization is direct action to resolve non-optimized radio resource utilization cases. Term of donor and receptor are applicable for those identified cells. The identification has to consider long term traffic trend and increment factor of traffic during normal session (average daily) and peak session (Lebaran, Christmas, New Year, etc.). TRX downgrade and upgrade on the particular cells is main activity of capacity balancing. Channel type reconfiguration can also be done with less capacity gain.