CDMA / EVDO CELL COVERAGE ANALYSIS - Actix Spotlight Desktop User Guide

You can use this analysis to:



Determine the coverage footprint for each cell.



Visualize where a cell is the best server.



Determine the relative grade of service as regards to EcIo, Mobile Rx Power and Mobile TX Power for selected cell(s), based on user-defined thresholds.



Visualize where cells are overshooting their coverage design boundary, as defined by SL_Overspill_Dist_Threshold, shown by the red line

surrounding a selected cell.

7.2.1 Before you start

You can use scanner or handset data for this analysis.

7.2.2 Using the cell coverage analysis

1 Click on an appropriate issue link (or on the Radio Network Explorer image followed by the Cell Coverage tab) to open the Cell Coverage analysis page.

2 Note that drive test data is binned according to the selections made in

step 4 of defining the project template. However, any events displayed on the map (for example, by using the Events drop-down menu) will use the exact position rather than a binned position, so events might not align with the data points.

2 From the top table, click on the column heading # > Dist. to sort the table by this value.

3 Look for differences between the # > Dist. value and # Samples. Be careful not to include sectors with low sample counts (for example, below 50) as these will not be statistically relevant.

Here is one such site - Site A, Sector 3. Some samples (highlighted) are shown well outside the overspill threshold (the red circle around the selected cell) and close to another cell.

2 4 In this example, scanner data is available, so select the Analysis to be

Scanner - Where Seen to visualize the coverage situation for the loaded data.

2 Continuing to investigate the sectors from the top table, we find another

potential problem sector, Site B Sector 2.

There may be a problem with the highlighted neighboring sector, which could be solved by downtilting the selected sector. First, check that the two cells are two- way neighbors.

7.2.3 Features of this analysis page



Top Panel - Shows summary information. Clicking on a row in this table

causes the side panel to display more information about the site, and the map zooms to the site and displays its coverage.



Map - When you click a row in the top table or on a site on the map, the

map shows the coverage wedge for the selected cell, EcIo and the

CDMA_Important_Issues (CDMA Grade of Service) attribute. The red circle represents the coverage design boundary, configured using

SL_Overspill_Dist_Threshold. Data points outside this circle represent overspill.



Side Panel - When no rows are selected, the side panel displays overview

information. A table shows details of the sites: Best EcIo, Rx Power, and CDMA Grade of Service. When a site is selected, the panel shows various KPI values for the site and a histogram of the distances at which the cell was measured. A red line indicates the maximum range for the analysis, as defined by SL_Overspill_Dist_Threshold.



Filters – Select this link to specify filters for the table on the top panel.



Attributes – List of most commonly used attributes that can be plotted on

the map. Currently plotted attributes are shown in red in the list. The currently selected attributes will be kept as you move between Spotlight's analysis pages.



Events – List of the event attributes that can be plotted on the map. So

while looking at pilot pollution you could dump the CDMA Dropped Call event on the map and quickly find out if the call dropped due to pilot pollution. Currently plotted events are shown in red in the list.



Analysis – Select Scanner (Best Server/Where Seen) or Handset (Best

Server/Where Seen) analysis. The analysis can operate in two modes: Best Server and Where Seen. Changing the mode affects the Ec/Io

attribute that is displayed on the map. Best Server mode shows the Ec/Io when the selected cell was the best server is displayed. Where Seen mode shows the Ec/Io whenever the cell was measured, and shows the coverage footprint for only those cells that were the best servers at some point in the drive.



PN Search – Visualize a PN on the map. Select a PN to color red all the

sites with this PN, so you can quickly identify co-PN locations.



Overview – Displays in the left panel an overview of statistics, plus Grade

of Service percentages for the entire drive. The map also shows the Grade of Service (the legend also shows sample counts).

This table shows how the CDMA Grade of Service is computed at each point: CDMA Grade of

Service EcIo condition* MRx Power condition* MTX Power condition*

Excess interference Within Exceed Within

External interference Within Exceed Exceed

Weak reverse link Exceed Exceed Exceed

Weak forward link Within Within Within

Low Rx signal Exceed Within Exceed

Poor coverage Within Within Exceed

*Conditions:



EcIo compared with CDMA_EcIoCombinedThreshold - This condition is used in conjunction with Mobile Rx Power and Mobile Tx Power Thresholds to determine the diagnosis for the dropped call, failed call and voice call with poor quality. Recommended value is -12 dB. Values should vary between -16 and -12 dB.



Mobile Rx Power compared with CDMA_MobileRxPowerThreshold - This condition is used in conjunction with EcIo and Mobile Tx Power Thresholds to determine the diagnosis for the dropped call, failed call and voice call with poor quality. Recommended value is -80 dBm. Values should vary between -75 and -90 dBm.



Mobile Tx Power compared with CDMA_MobileTxPowerThreshold - This condition is used in conjunction with EcIo and Mobile Rx Power Thresholds to determine the diagnosis for the dropped call, failed call and voice call with poor quality. Recommended value is 5 dBm. Values should vary between 0 and 10 dBm.

In document Actix Spotlight Desktop User Guide (Page 44-50)