Significance of Kssb value read from the MIB for a ENDC UE?

5G NR
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1

Hi All.
Is there any significance of Kssb value read from the MIB for a ENDC UE?
Since SSbfreq n PointA freq are already available.
In Reconfiguration msg for NR cell addition.

2

Some chipset vendor use kssb value to check the presence of Coreset 0 even in case of endc also.
Example if kssb value indicate that coreset 0 is present but actually not configured in reconfig message then it will cause some problem…but it is chipset implementation specific only in endc case.

3

But anyway the UE doesn’t need the coreset0 since its not required to read sib1…
So why does coreset 0 become revelant here?

4

But you can configure coreset0 in case of endc also via reconfig message.

5

Yup…
But if I don’t want to configure it… Can I give any value I want in kssb and it won’t matter for an Endc UE?

6

Samsung device does not like any value …it ahould be compatible with presence/absence of coreset0.
Qcom UE ignore kssb value in case of endc.

7

Which is strange thinking UE doesn’t need it for any purpose if it’s not configured in reconfiguration message.

8

We observe this issue with S10 device.

9

Sorry for “waking up” the discussion, but the ssb-SubcarrierOffset isn’t required to perform, for instance, measurement based addition of 5GNR?
Assuming it will receive it prior to the RRC Reconfiguration with the full setup of the PSCell?

10

For measurements, we give the absolute freq of SSB…
So I cannot see Kssb used in that.

11

I saw different implementation. Like one vendor configure it in MIB and other configure in rrc reconfig while MIB showing “0” value

12

True that, well remembered!

13

It will always be present in the MIB i think it’s not optional.

14

I mean for coreset#0 its optional through mib or rrc reconfig message.

15

No significant, in the case of NSA( ENDC), for PScell and Scells the network provides the required SI by dedicated signalling, i.e within an RRC reconfiguration message.

Nevertheless,the device shall acquire MIB of PScell to get SFN timing of the SCG which may be different from MSG.

16

Theoretical that should be…
But from answers above it seems to be left on UE implementation?

17

As per 38.213 (Clause 4.1), UE determines If a control resource set zero for Type0-PDCCH common search space is present if following criteria is meet, Upon detection of a SSB, the UE determines that a control resource set for Type0-PDCCH common search space is present if Kssb<=23 for FR1 and if Kssb is <= 11 for FR2 .

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