4G Strategy : Adaptive SFN to Improve Performance

Background:

This feature recommends 2 to 3 RF modules that provide coverage in different areas to serve one SFN cell, with the overlapping areas between non-SFN cells becoming part of the SFN cell center. Joint scheduling is thereby performed for all UEs in the ASFN overlapping cell to reduce interference. When there are only a few users and low network load, this feature obviously improves user experience.

Parameter Setting :

1	Deactivate cells 11 21 31
2	Remove sector equipment 11 from cell 11, 31 from cell 31
3	Turn off UlJointReceptionSwitch under Uplink Comp Switch in the CellAlgoSwitch
4	Change the Flag of Multi-RRU Cell parameter value of cell 21
5	Bind sector equipment 11 and 31 to cell 21
6	Changed the SRS configuration indicator.
7	Activate ASFN cells

Fact Finding:

SFN can be deployed in the first phase to reduce interference and handover times , and improve the user experience. Adaptive SFN can be deployed in the second phase to improve the network capacity when the cell load is higher.

Analysis:

Different with SFN, ASFN will only use Joint Scheduling (receives signals from multi-RRU) if:

•The load of the RRU is light (for example, less than 30%).

•The equivalent RSRP difference between the RRU and the benchmark RRU is less than 30 dB.

High Isolation Users use Independent scheduling(receive signals only from the target RRU with the different RBs).

Pro :

•Improve network capacity if compared with SFN because still can cover high isolation user method

•

Cons :

If PRB is high, DL throughput in overlapping area maybe deteriorate