NR Inter Band CA capability parameter

Hello Expert,
do you know if the support of the parameter: “Simultaneous Rx Tx InterBand CA”, imply that UE support Inter band NR CA?

The definition of this parameter is: “Indicates whether the UE supports simultaneous transmission and reception in TDD-TDD and TDD-FDD inter-band NR CA. It is mandatory for certain TDD-FDD and TDD-TDD band combinations defined in TS 38.101-1 [2], 38.101-2 [3] and 38.101-3 [4].”

However, I’ve found some devices that doesn’t declares interband NR CA combinations, even if that parameter is supported.

Can you please help me about that?


Hi Mike,
UE will support CA for band combinations as it indicated under its capability , provided both bands use same slot format with same SCS, even UE does not support simultaneous RX TX for the given band combination.

BTW, may I know where do you see device supports simulations rx tx parameter without showing band capability support?


Hi Deepak,
sometimes, in the enquiry message I have to verify the support for only one NR band, so I can’t see all the combinations supported by device. For instance, if the enquiry message requests support only for LTE bands 10,20,30,40 and NR band 50, the mobile gives EN-DC combinations only with LTE bands and NR Band 50.
I would like to understand if in cases like these, there is a parameter in the capability response, which indicates the support of the Interband NR CA.