How the gNB knows which resources are used for URLLC and which for eMBB?

RAN
1

Hi Experts.

When URLLC and eMBB both traffic exist, the UE may puncture the eMBB to transmit URLLC.

Does anyone know how the gNB knows which resources are used for URLLC and which for eMBB?

And should the gNB be prepared for such event?

Whether standards support indication of puncturing…

2

Is it related to network slicing in SA?

We have Slice Service Type (SST) option to configure between eMBB/URLLC.

3

Yes, the 3GPP is supporting pre-emption as it is not called puncturing here and UE needs to monitor the preemption indication which is configured by RRC signaling to know that some parts of its PDSCH transmission is pre-empted and so not going to decode it wrongly.

The 5G BTS is aware about this pre-emption and assigns the URLLC using what is called mini-slot with different symbol lengths depending on the amount of URLLC data intended for transmission.

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4

Thank you very much!

Are you aware of any similar mechanims on the UL?
The one you describe here is DL preemption. Are you aware of UL?

5

Such a mechanism doesn’t exist in UL as in 5G, we use what is called Grant free (also known as configured grant in 3GPP) UL transmissions which allow the 5G BTS to configure periodic UL resources for a UE, when the UE has data, it can transmit on the configured resources.

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6

About network slicing, resource management is very important at RAN, transport, core.
Gnb should be able to configure RB regions dedicated for embb, urllc and shared resourced between them.

7

Hello @Ibrahim_Sayed

I have a query → To my understanding RAN side based on RIC and non-RIC commands only different services(EMBB, URLLC etc) will be configured(Resources will be allocated ) on specific BWP in a carrier BW So if this is the case for particular BWP, say BWP 1st is for EMBB and BWP 2nd is for URLLC and so on up to 4 BWP and respective devices will be using specific BWP based on there service requirement let’s say EMBB is for Mobile devices and URLLC is for IOT devices why the pre-emption is required ? Because already respective devices are working on there respective BWP ?

Could you please clarify on this ?