For NSA post SCG addition do we have NR to NR ANR by strongest cell and CGI reporting?

5G NR
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1

Hi Experts.

For NSA post SCG addition do we have NR to NR ANR by strongest cell and CGI reporting?

Or do we need to manually add 5G to 5G neighbours.

Does UE indicates such support to network for 5G to 5G neighbour and 5G to 4G neighbour?

Admin note: this post was updated with image below.
For NSA post SCG addition do we have NR to NR ANR by strongest cell and CGI reporting

2

Yes there is ANR in 5G but you need to activate sib1 at Nrcells first.

3

No sib1 in NSA case at NR…

4

Yes, in UE CAP there is an IE declaring UE support.

Here is a good topic you can check:

Are you sure?

I tested that feature and made rollout.

6

I was part of earlier discussion link :point_up_2:

At that time sib1 not under NSA.

Can you please share how to activate sib1 in NSA?

7

Which vendor?

Normally UE does not need sib1 in NSA but in case ANR for UE to decode CGI it first needs to decode MIB and Sib1 to extract CGI.

8

Yes for ANR it’s mandatory to read sib1.

We can list down all required IE support by UE for:

  1. 4g to 5g ANR in NSA
  2. 4g to 5g ANR in SA case
  3. 5g to 5g ANR in NSA case
  4. 5g to 5g ANR in SA case
  5. 5g to 4g ANR in SA case

Above all possible conditions

9

I am aware for one vendor, NR-NR ANR does not need SIB1 or UE support. It is created via the anchor

For LTE-NR ANR, SIB 1 is needed for UE to report NCGI

10

From 5G SA to 4G check these: :point_down:

11

Related with ANR in NSA 5G, and according to the comments in:

ANR in NSA 5G
ANR in NSA 5G1595×1255 209 KB

I think there are the 3 issues to review (I’m learning with this forum, only reading and summarizing what other experts commented some time ago):

  1. Enable SIB1 in 5G NSA
  2. Check if UE supports reportCGI-NR-EN-DC-r15 (0 means supported)
  3. Check if parameters allow measuring of SIB1 (for instance: DRX settings)

Please correct if I’m wrong.

12

How to enable sib1 in NSA?

Is it UE dependent? I mean some support needed from UE end as well or network only?

13

Enable SA on gNB but restrict SA access

14

According to the messages referred on the post, I think it’s NOT UE dependent.

I mean, after Network enabling (by setting parameters), only capable UEs (which can support “reportCGI-NR-EN-DC-r15”) will report measurements.

Previously, I think that some network optimization must be do to ensure UEs can work with this functionality (for instance: DRX settings)

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image1600×697 110 KB

15

There are two flavors of ANR:

  • UE based: will require the UE to measure and report NR-CGI by reading SIB1 of NR cell. If your network runs on NSA/SA dual mode, SIB1 will be there. UE needs to support this measurement by sharing reportCGI-NR-NoEN-DC-r15 and/or reportCGI-NR-EN-DC-r15. Once the UE reports the unknown PCI the eNodeB can ask 5GC/EPC for details about the target NR cell in order to create the X2/Xn, or ask OSS for its own database to obtain the information.

  • OSS based: requires no extra measurements from the UE. By regular measurement reports for regular mobility, if a unknown PCI is reported, the eNodeB will query the OSS for details about the target NR cell in order to create the X2/Xn.

Where I work, we did a manual creation of the initial list (based on cell refs, distance criteria, etc…) and then activated ANR UE Based on top of it.