over shooting analysis

HUAWEI TECHNOLOGIES CO., LTD.

3G Overshooting Analysis

HISILICON SEMICONDUCTORHUAWEI TECHNOLOGIES CO., LTD.

Content

Analysis Indicator

TP analysis

Per Neighbor stats

Google check

Tilt Calculation


Overhooting Concept

› Specify theoretical serving distance based on site to site distance per clutter type.

› Create short list from TP stats.› Create short list from per neighbor stats.› Check the cells which is in short list from the google-earth one by one

to confirm.› Calculate the tilts with the tool based on antenna height, type and

terrain height.


TP Analysis› The Physical Random Access Channel (PRACH) is the only common

channel on which the uplink open loop power control is applied.› The UE transmits the first preamble to the NodeB to start an access

process. Till the AICH received by the Ue successfully, Ue keep sending preamble till reach MaxPreamble Number and Max Ue power which is defined with the parameters.

› RNC calculates the TP value(speed and time) and the number of sample(by successful message)


TP Analysis(Example)› You can see in below, raw data of TP values versus Number of Ec/No

and Mean Ec/No.


TP Analysis(Example)› To create pivot table, we revert the TP values to distance, the formula

for it is like below› Distance(m)=(TP+117)*234


TP Analysis(Pivot to analyze)› To create pivot table, we revert the TP values to distance, the formula

for it is like below› Distance(m)=(TP+117)*234


SHO Per Neighbor Stats› We take SHO per neighbor stats which is showing SHO attempts per

relations for each cell.› Calculate the Distance for each relation by using below formula in excell.

SQRT((C2-F2)^2+(D2-

G2)^2)*100 C2=Lon1 D2=Lat1F2=NLon G2=NLat


SHO Per Neighbor Stats› By Neighbouring Cell Name, SUM of Total Attempts, AVG of Distance› Enough only to analyze F1,Sort By Sum of Total Attempts› This will give you a “Score” of how dominant a Cell is in a Cluster, and

the Average Distance of Other Cells which register it as a Nbr from MR Data,If a Cell is very dominant, it could indicate Overshooting


Google Check› For the short list that we create from TP and the SHO per neighbor stats,

we need to confirm that site location and site to site distance in the area which means real situation of the overshooting cells.

~

Elevation profile feature of google earth is very usefull to confirm and finalized the overshooting list to pass the calculation stage.


Tilt Calculation(Theory)› Final Part of the Overshooting cells optimization is the Tilt calculation

of the overshooters.Below graph and the formula is showing theoretical calculation.

› Formula; Arctanα=k+h

α

kd

h

α

dα=Tilt anglek=Terrain differenceh=Antenna heightd=Distance that we want to serve


Tilt Calculation(tool)› We don’t calculate the tilts one by one by manually. We use tool(is

using the formula that we explain previous slide) that calculate the tilts automatically which is like below.

over shooting analysis

Documents