DAS Optimization Considerations
DAS systems are an effective way of adding coverage and capacity and have become an integral part of a wireless network to provide an effective solution in challenging RF environment. DAS solution deployed in various environments requires Optimization of the network in order to meet network performance requirements and excellent customer experience.
Macro Mitigation: The DAS system has to be optimized to overcome the strong macro coverage so it can get the right amount of isolation between DAS and Macro. Important part of Optimization of these venues is to conduct macro reduction exercise using tools like OptPCS iCE to help improve the DAS performance with minimal acceptable changes to macro network.
Signal/Noise: The Performance of the DAS system is not related to the absolute Signal level but rather the quality of the signal. While system generated noise is always present, reducing external interference and Pilot Pollution will help to have high SINR which in turn leads to better performance.
UL and DL Attenuation: It is necessary to adjust the UL and DL Attenuation when connecting the DAS to the enodeB for power control, link balance, System info and timing parameters.
Neighbor Optimization: All Intra and Inter neighbors for the DAS system have to be optimized to ensure seamless handovers between the DAS sectors as well as surrounding macro site. The soft handover SHO factor has to be optimized for maximum traffic and minimum system overheads.
Layer Management: Most DAS systems are multi carrier and multiple technologies, the traffic has to be balanced between all Layers to get the most out of all system resources.
Inter Frequency (IFHO): Intra System and Inter- System handover are minimized for maximum DAS coverage and smooth handovers between the DAS and Macro. It is optimized to reduce the amount of time the UE is in compressed mode.
Idle Mode: Cell selection/reselection parameters are defined to direct subscribers to the appropriate cells/ bands for the purposes of even traffic distribution.
RACH/PRACH Optimization: RACH/PRACH are important UL Channels to request for call service or packet service. This channel is also a source of interference against Traffic channels. The parameters relating to RACH/PRACH need to be optimized based on the RF Environment and the cell capacity to ensure that the UL Channel capacity is maximized.
Hi Cap Parameters: Hi Cap venue systems are designed to maximize the traffic handling, the RF Parameters also needs to be aligned appropriately.