What is stop criteria for TTT?

Hello device experts,
I want to know: once device start TTT for particular event, what is stop criteria for TTT?
I mean when can TTT stop?
If entering condition is not met?
If leaving condition is met?

1 Like

This can help:

LTE UE event Measurement Reporting-Event A1,A2,A3,A4,A5,B1,B2

https://www.rfwireless-world.com/Terminology/LTE-UE-Event-Measurement-Reporting.html

Thank you @marcengo.
I went through many such explainations.
It gives very rough explanation and doesnt give answer to my question precisely.
When does TTT stop?

It stops when it expires, and when it expires, the UE sends the MR.
Once the condition for the event is met (after filtering, etc…) the UE starts the TTT. If the conditions holds until the TTT expires, the UE sends the MR.

Expiry is ok.
But before expiry, what is the condition to stop? If entering condition is not met or if leaving condition is met?
I am talking about what makes it stop before expiry?

My understanding is, once you start TTT it will run until it ends, assuming here no reportOnLeave.

This is the answer for your question!

It means entering condition should hold true till TTT expires, right?

2> if the triggerType is set to ‘event’ and if the entry condition applicable for this event, i.e. the event corresponding with the eventId of the corresponding reportConfig within VarMeasConfig, is fulfilled for one or more applicable cells for all measurements after layer 3 filtering taken during timeToTrigger defined for this event within the VarMeasConfig while the VarMeasReportList does not include a measurement reporting entry for this measId (a first cell triggers the event):

It means if it holds true, the UE sends the MR.

Let me show background of my query.
Hysterysis value is any event is used for Entry condition and leaving condition of event
If Report on Leave is FALSE for all events, then what is i the use of hysteresis?

image

I also think TTT is started at range+hyst and it is stopped at range-hyst.

You mean at leaving condition it TTT stops?

TTT is stoped during TTT running if condition range–hyst is not fulfilled anymore.

Range - Hyst is leaving condition.

Take as example a3 in LTE with range 3db and HYST 2 dB.
So TTT starts at 5dB and stops at 1db.

That’s a good suggestion as well.

Yes. But this is contradicting at what written in specs:

2> if the triggerType is set to ‘event’ and if the entry condition applicable for this event, i.e. the event corresponding with the eventId of the corresponding reportConfig within VarMeasConfig, is fulfilled for one or more applicable cells for all measurements after layer 3 filtering taken during timeToTrigger defined for this event within the VarMeasConfig while the VarMeasReportList does not include a measurement reporting entry for this measId (a first cell triggers the event):

I see no mention on this on 36.331, assuming once again, reportOnLeave as false.

I agree with you.

But still, is reasonable. I’m looking to see if I find a log with this scenario.