Method and apparatus for transmitting buffer status report by wireless node in wireless communication system

1. A method for transmitting a buffer status report (BSR) by a wireless node in a wireless communication system, the method comprising:

receiving first logical channel group (LCG) configuration information including identities of LCGs from a network;

generating the BSR including a LCG field; and

transmitting the BSR to the network,

wherein a length of the LCG field is configured according to a highest value of the identities of LCGs, and

wherein, based on the identities of LCGs being related to an Integrated access and backhaul (IAB) node, the highest value of the identities of LCGs is greater than or equal to 8.

2. The method of claim 1 , further comprising:

receiving second LCG configuration information from the network; and

reconfiguring the length of the LCG field according to a highest value of the identities of LCGs included in the second LCG configuration information.

3. The method of claim 1 , wherein each bit of the LCG field indicates whether buffer size information of a corresponding LCG is present or not in the BSR.

4. The method of claim 1 , wherein, the length of the LCG field is configured to floor(Y/8) plus 1 bytes, when highest value of the identities of LCGs is equal to or larger than Y and less than Y+8,

wherein Y is multiple of 8.

5. The method of claim 1 , wherein a number of the identities of LCGs is variable according to a number of nodes served by the wireless node.

6. The method of claim 1 , wherein a number of the identities of LCGs is variable according to a number flows or a number of radio bearers served by the wireless node.

7. A wireless node in a wireless communication system, the wireless node comprising:

a memory; and

at least one processor coupled to the memory,

wherein the at least one processor is configured to:

receive first logical channel group (LCG) configuration information including identities of LCGs from a network;

generate a buffer status report (BSR) including a LCG field; and

transmit the BSR to the network,

wherein a length of the LCG field is configured according to a highest value of the identities of LCGs, and

wherein, based on the identities of LCGs being related to an Integrated access and backhaul (IAB) node, the highest value of the identities of LCGs is greater than or equal to 8.

8. The wireless node of claim 7 , wherein the at least one processor is further configured to:

receive second LCG configuration information from the network; and

reconfigure the length of the LCG field according to a highest value of the identities of LCGs included in the second LCG configuration information.

9. The wireless node of claim 7 , wherein each bit of the LCG field indicates whether buffer size information of a corresponding LCG is present or not in the BSR.

10. The wireless node of claim 7 , wherein, the length of the LCG field is configured to floor(Y/8) plus 1 bytes, when highest value of the identities of LCGs is equal to or larger than Y and less than Y+8,

wherein Y is multiple of 8.

11. The wireless node of claim 7 , wherein a number of the identities of LCGs is variable according to a number of nodes served by the wireless node.

12. The wireless node of claim 7 , wherein a number of the identities of LCGs is variable according to a number flows or a number of radio bearers served by the wireless node.

13. The wireless node of claim 7 , wherein the at least one processor is further configured to implement at least one advanced driver assistance system (ADAS) function based on signals that control the wireless node.