NR Carrier Aggregation: Decoding bandwidth combination sets and CA configurations

Hello Experts.

Regarding NR intra-band contiguous CA, what does CA_n41c(4) signify? I see the bandwidth combination set mentions “4” - what does this value represent?

Similarly, for inter-band NR CA, in CA_n1A_n3(2), the bandwidth combination set is “2” - what does that indicate?

For CA_n2(2A)_n77(2A), does it imply something like CA_n2AA_n77AA, meaning both downlink and uplink CA between band 2 and band 77 are possible?

Admin note: this post was updated with image below.

I don’t think the value should be 4 here.

Could you share a snippet of that part for clarification?

Bandwidth combination set points towards a table which tells possible channel Bandwidth combination a UE can support. It can have multiple combination.

For example in your case of intra band contiguous CA_n41c with Bandwidth combination set value is let say 3 = 11 (in binary)

Here from the below table UE support below possible Bandwidth combinations as i marked.

But maximum aggregate Bandwidth won’t exceed the value which is defined here.

Just refer 38.101-1 for more details.

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Thanks, I understood the concept of the bandwidth combination set.

Just to add, the supported bandwidth combination set IE, part of the supported band combination list, shows that the leftmost bit (bit 0) corresponds to bandwidth combination set 0 for a particular band combo.

We then need to refer to the tables for CA band combinations in 38.101.

If the 2nd bit is set to 1, it indicates that the same band combo can use bandwidth combination set 1.