High PS Failure but excellent CS retainability

[tthach830]

Hi all,

I have been chasing this problem for almost a week now and could not find what the problem is:

Problem: My stat is showing very high PS drops on 3 sites; however CS failures is very low. I have check hardware and could not find any issue. The nbr sites are not affected by this stat.

This problem come and go. It also seems to go away for a day after a site restart.

This problem started a few weeks ago.
Any guidance to where else to look at would be greatly appreicated.

[MONEY]

Hi all,

I have been chasing this problem for almost a week now and could not find what the problem is:

Problem: My stat is showing very high PS drops on 3 sites; however CS failures is very low. I have check hardware and could not find any issue. The nbr sites are not affected by this stat.

This problem come and go. It also seems to go away for a day after a site restart.

This problem started a few weeks ago.
Any guidance to where else to look at would be greatly appreicated.

Run a UE trace & find out is it the Ps fail coz by single UE?
is the UL RSSI ok?
how bout CC Irat succ count?

[tthach830]

RSSI is ok. If it is then it would affect voice too.

CC IRAT Success is low;however this is normal.
The hourly stat as of today is good. I am not seeing dramatic PS retainability issue.

[anita_2k]

Hi all,

I have been chasing this problem for almost a week now and could not find what the problem is:

Problem: My stat is showing very high PS drops on 3 sites; however CS failures is very low. I have check hardware and could not find any issue. The nbr sites are not affected by this stat.

This problem come and go. It also seems to go away for a day after a site restart.

This problem started a few weeks ago.
Any guidance to where else to look at would be greatly appreicated.

Which vendor? check the attempts/traffic both for CS/PS if still normal.

[tthach830]

Which vendor? check the attempts/traffic both for CS/PS if still normal.

E///. Attemtps and traffic are normal.

HS Drops is normal too; so R99 is the culprit. I am assuming PS_Drops = HS + R99.

[chaosnoise]

E///. Attemtps and traffic are normal.

HS Drops is normal too; so R99 is the culprit. I am assuming PS_Drops = HS + R99.

Do you have Uu, Iu-ps logs? I can take a look at them if you donot mind.

[tthach830]

After further analysis, most of the drops are due to downgrading or switch from HS to R99. Most of attempts are 99% HS and less than 1% R99; however most of the PS drops are on R99.

So how do I find out what causing this R99 drops with voice accessibility/retainility are great? Is there a flowchart for how this R99 dropsped counter is pegged?

[the.rf.consultant]

try to look at what services R99 was utilizing (maybe data call) and how it is utilizing the network PS channel resources.

ultimately you have to review the RNC ChannelSwitching parameters that might have settings too stringent for the downswitching of HS to R99 causing the failure.

[tthach830]

This doesn't happened everyday. In fact it's been working fine for the last 2 days now. It's an intermitten issue.

I am now looking at the flowchart for downswitch counters and see how the counters are pegged.

Any further suggestion would be appreciated.

[adewijaya]

you have 1 carrier or 2 carrier and what kind layering strategy?