What happens if DSS deployed at network end for NR SA and UE doesn't support crsratematching?

Hello NR DSS Experts.

If DSS deployed at network end for NR SA and UE doesn’t support crsratematching then what will happen?

Will such UE able to access cell or does it gets failed?

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CRS Rate Matching is a parameter that influences how data is transmitted around the reference signals that are not intended for the particular UE. Specifically, this parameter is used to avoid data being transmitted on the resources that the UE would use to receive the CRS, thereby preventing interference and potential data loss in those regions of the spectrum.

If UE Do Not Suppoert CRS Rate Matching , possible to be reject because of cannot decode Channel Estimation , Cell dentification and possible to could not receive quality measurement messages.

Summarily not supporting CRS Rate Matching can lead to various performance issues for a UE in a 5G NR SA network environment, primarily revolving around how effectively it can handle downlink transmissions in the presence of cell-specific reference signals.

  • Increased Interference: Without CRS Rate Matching, the UE might not be able to effectively exclude the CRS from the PDSCH data decoding process. This could lead to increased interference from these signals, potentially degrading the performance of the downlink data transmission.
  • Decreased Data Throughput: Interference typically results in lower signal quality, which can reduce the data throughput rate. This means the UE might experience slower data speeds and reduced overall network performance.
  • Higher Error Rates: Increased error rates can occur due to the interference from the CRS signals. The UE’s receiver might incorrectly decode data, leading to increased retransmissions and further reducing efficiency.
  • Network Compatibility Issues: In some cases, if the UE lacks certain capabilities like CRS Rate Matching, it might face broader compatibility issues with certain network configurations or advanced features that rely on this functionality to optimize signal integrity and resource allocation.
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Is this parameter not mandatory for UE to support DSS feature?

I am not sure if it is mandatory or not for DSS, but aproximately it can be mandatory because that is one parameter is important during Rach procedure.

This parameter defines the rate matching factor of the RACH, so I guess / hope it can be mandatory.

If UE doesn’t support “rateMatchingLTE-CRS” then the UE won’t be able to access 5G DSS cell. However it can still connect and function on 4G cell as normal.

Great explanation, I am assuming the UE declare its CRS rate matching capability in the UE capability message it sends to the network? Can anyone share a snapshot of that message showing the parameter.

In blue
image

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