Scenario which include cells with different frequencies, not CA, possible for UE to change BWPs during sim??

[Kamil Kociszewski]

Hi,

i'm now trying to build scenario with different bands,
for example one cell with band 3500 and one with band 700.

I'm able to have it both in one scenario and attach UEs manually to them, but BWP for UE also need to be predefined(?).
If i try to use allBwps = CcBwpCreator::GetAllBwps({band1, band2});
UEs do not connect to cells with band2 (no traffic, no RSRP, manual attach to band 700 cell).

NetDeviceContainer ueNetDev = nrHelper->InstallUeDevice(ueNodes, allBwps);

I can be wrong with that approach, but is it possible to define UEs with no predefined BWPs, that will allow to move UEs between frequencies (when HOs will be implemented)?

I see example with CA, but this one is defined as two frequencies in one cell (?).

[Gabriel Ferreira]

> I'm able to have it both in one scenario and attach UEs manually to them, but BWP for UE also need to be predefined(?).

Yes. 

> UEs do not connect to cells with band2 (no traffic, no RSRP, manual attach to band 700 cell).

As far as I know, we only support a single cell, which may have aggregated carriers. Dual-connectivity is more complicated.

>  I can be wrong with that approach, but is it possible to define UEs with no predefined BWPs, that will allow to move UEs between frequencies (when HOs will be implemented)?

This is work in progress. But UEs need to know the BWP regardless (if we continue following LTE design), otherwise they cannot listen for MIB and SIB, which are used to configure RRC/MAC/PHY and attach on demand.

[Kamil Kociszewski]

Thank you Gabriel,

> UEs do not connect to cells with band2 (no traffic, no RSRP, manual attach to band 700 cell).

As far as I know, we only support a single cell, which may have aggregated carriers. Dual-connectivity is more complicated.

I mean here,
if i predefine two BWPs for UE with: allBwps = CcBwpCreator::GetAllBwps({band1, band2});

and manually attach UE to band2: nrHelper->AttachToGnb(ueVoiceNetDevAllBwps.Get(0), gnbNetDevband2.Get(0));
it seems not working as assumed.

If i connect same UE to band1: nrHelper->AttachToGnb(ueVoiceNetDevAllBwps.Get(0), gnbNetDevband1.Get(0));
it's working correct.

Where band1 is 3500 MHz and band2 is 700 MHz.

OperationBandInfo band1 = ccBwpCreator.CreateOperationBandContiguousCc(bandConf1);
OperationBandInfo band2 = ccBwpCreator.CreateOperationBandContiguousCc(bandConf2);

BWP3500 = CcBwpCreator::GetAllBwps({band1});
BWP700 = CcBwpCreator::GetAllBwps({band2});