Chapter 20
Wireless Network Optimization
The first step in optimizing a network is to optimize the sites' footprint to minimize interference while assuring enough overlap for handovers. The next step is to generate a Neighbor list and calculate handover thresholds, if required. Then an Interference Matrix (IM) should be generated, based on signal outage. Finally, resources can be optimally assigned considering the relationships of the IM.
20.1 Cell Enhancement or Footprint Optimization
Wireless systems are implemented with overlap between cells to provide mobility from one cell to another and to avoid coverage “holes”; however, overlapping increases interference and, consequently, may diminish network capacity.
Achieving the proper amount of overlap while simultaneously minimizing interference and maintaining the coverage area is a very daunting task, but it may significantly increase network capacity. Footprint optimization tools, also known as automatic cell planners (ACP), automatically shape cell footprints to enhance network performance by minimizing interference (considering diversity effects) while maintaining coverage, and balancing traffic distribution. In this section, we use the tool CelEnhancer as an example.
This enhancement of the cell footprint is done by selecting the best antenna parameters within limits specified by the designer. The antenna parameters that can usually be adjusted are:
- antenna type
- antenna azimuth
- antenna downtilt
- antenna height
- transmit power ...
